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Nielsen GH, Heiger-Bernays WJ, Levy JI, White RF, Axelrad DA, Lam J, Chartres N, Abrahamsson DP, Rayasam SDG, Shaffer RM, Zeise L, Woodruff TJ, Ginsberg GL. Application of probabilistic methods to address variability and uncertainty in estimating risks for non-cancer health effects. Environ Health 2023; 21:129. [PMID: 36635712 PMCID: PMC9835218 DOI: 10.1186/s12940-022-00918-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Human health risk assessment currently uses the reference dose or reference concentration (RfD, RfC) approach to describe the level of exposure to chemical hazards without appreciable risk for non-cancer health effects in people. However, this "bright line" approach assumes that there is minimal risk below the RfD/RfC with some undefined level of increased risk at exposures above the RfD/RfC and has limited utility for decision-making. Rather than this dichotomous approach, non-cancer risk assessment can benefit from incorporating probabilistic methods to estimate the amount of risk across a wide range of exposures and define a risk-specific dose. We identify and review existing approaches for conducting probabilistic non-cancer risk assessments. Using perchloroethylene (PCE), a priority chemical for the U.S. Environmental Protection Agency under the Toxic Substances Control Act, we calculate risk-specific doses for the effects on cognitive deficits using probabilistic risk assessment approaches. Our probabilistic risk assessment shows that chronic exposure to 0.004 ppm PCE is associated with approximately 1-in-1,000 risk for a 5% reduced performance on the Wechsler Memory Scale Visual Reproduction subtest with 95% confidence. This exposure level associated with a 1-in-1000 risk for non-cancer neurocognitive deficits is lower than the current RfC for PCE of 0.0059 ppm, which is based on standard point of departure and uncertainty factor approaches for the same neurotoxic effects in occupationally exposed adults. We found that the population-level risk of cognitive deficit (indicating central nervous system dysfunction) is estimated to be greater than the cancer risk level of 1-in-100,000 at a similar chronic exposure level. The extension of toxicological endpoints to more clinically relevant endpoints, along with consideration of magnitude and severity of effect, will help in the selection of acceptable risk targets for non-cancer effects. We find that probabilistic approaches can 1) provide greater context to existing RfDs and RfCs by describing the probability of effect across a range of exposure levels including the RfD/RfC in a diverse population for a given magnitude of effect and confidence level, 2) relate effects of chemical exposures to clinical disease risk so that the resulting risk assessments can better inform decision-makers and benefit-cost analysis, and 3) better reflect the underlying biology and uncertainties of population risks.
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Affiliation(s)
- Greylin H Nielsen
- Department of Environmental Health, Boston University School of Public Health, 715 Albany Street, T4W, Boston, MA, 02118, USA
| | - Wendy J Heiger-Bernays
- Department of Environmental Health, Boston University School of Public Health, 715 Albany Street, T4W, Boston, MA, 02118, USA.
| | - Jonathan I Levy
- Department of Environmental Health, Boston University School of Public Health, 715 Albany Street, T4W, Boston, MA, 02118, USA
| | - Roberta F White
- Department of Environmental Health, Boston University School of Public Health, 715 Albany Street, T4W, Boston, MA, 02118, USA
| | | | - Juleen Lam
- Department of Public Health, California State University, East Bay, Hayward, CA, USA
| | - Nicholas Chartres
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Dimitri Panagopoulos Abrahamsson
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Swati D G Rayasam
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Rachel M Shaffer
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, WA, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA, USA
| | - Tracey J Woodruff
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Gary L Ginsberg
- Department of Environmental Health Sciences, School of Public Health, Yale University, New Haven, CT, USA
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2
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Woodruff TJ, Rayasam SDG, Axelrad DA, Koman PD, Chartres N, Bennett DH, Birnbaum LS, Brown P, Carignan CC, Cooper C, Cranor CF, Diamond ML, Franjevic S, Gartner EC, Hattis D, Hauser R, Heiger-Bernays W, Joglekar R, Lam J, Levy JI, MacRoy PM, Maffini MV, Marquez EC, Morello-Frosch R, Nachman KE, Nielsen GH, Oksas C, Abrahamsson DP, Patisaul HB, Patton S, Robinson JF, Rodgers KM, Rossi MS, Rudel RA, Sass JB, Sathyanarayana S, Schettler T, Shaffer RM, Shamasunder B, Shepard PM, Shrader-Frechette K, Solomon GM, Subra WA, Vandenberg LN, Varshavsky JR, White RF, Zarker K, Zeise L. A science-based agenda for health-protective chemical assessments and decisions: overview and consensus statement. Environ Health 2023; 21:132. [PMID: 36635734 PMCID: PMC9835243 DOI: 10.1186/s12940-022-00930-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2022] [Indexed: 06/17/2023]
Abstract
The manufacture and production of industrial chemicals continues to increase, with hundreds of thousands of chemicals and chemical mixtures used worldwide, leading to widespread population exposures and resultant health impacts. Low-wealth communities and communities of color often bear disproportionate burdens of exposure and impact; all compounded by regulatory delays to the detriment of public health. Multiple authoritative bodies and scientific consensus groups have called for actions to prevent harmful exposures via improved policy approaches. We worked across multiple disciplines to develop consensus recommendations for health-protective, scientific approaches to reduce harmful chemical exposures, which can be applied to current US policies governing industrial chemicals and environmental pollutants. This consensus identifies five principles and scientific recommendations for improving how agencies like the US Environmental Protection Agency (EPA) approach and conduct hazard and risk assessment and risk management analyses: (1) the financial burden of data generation for any given chemical on (or to be introduced to) the market should be on the chemical producers that benefit from their production and use; (2) lack of data does not equate to lack of hazard, exposure, or risk; (3) populations at greater risk, including those that are more susceptible or more highly exposed, must be better identified and protected to account for their real-world risks; (4) hazard and risk assessments should not assume existence of a "safe" or "no-risk" level of chemical exposure in the diverse general population; and (5) hazard and risk assessments must evaluate and account for financial conflicts of interest in the body of evidence. While many of these recommendations focus specifically on the EPA, they are general principles for environmental health that could be adopted by any agency or entity engaged in exposure, hazard, and risk assessment. We also detail recommendations for four priority areas in companion papers (exposure assessment methods, human variability assessment, methods for quantifying non-cancer health outcomes, and a framework for defining chemical classes). These recommendations constitute key steps for improved evidence-based environmental health decision-making and public health protection.
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Affiliation(s)
- Tracey J Woodruff
- Program On Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 490 Illinois Street, Floor 10, Box 0132, San Francisco, CA, 94143, USA.
| | - Swati D G Rayasam
- Program On Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 490 Illinois Street, Floor 10, Box 0132, San Francisco, CA, 94143, USA
| | | | - Patricia D Koman
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Nicholas Chartres
- Program On Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 490 Illinois Street, Floor 10, Box 0132, San Francisco, CA, 94143, USA
| | - Deborah H Bennett
- Department of Public Health Sciences, University of California, Davis, Davis, CA, USA
| | - Linda S Birnbaum
- National Institutes of Environmental Health Sciences and National Toxicology Program, Research Triangle Park, NC, USA
- Duke University, Durham, NC, USA
| | - Phil Brown
- Social Science Environmental Health Research Institute, Northeastern University, Boston, MA, USA
| | - Courtney C Carignan
- Department of Food Science and Human Nutrition, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Courtney Cooper
- Program On Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 490 Illinois Street, Floor 10, Box 0132, San Francisco, CA, 94143, USA
| | - Carl F Cranor
- Department of Philosophy, University of California, Riverside, Riverside, CA, USA
- Environmental Toxicology Graduate Program, College of Natural and Agricultural Sciences, University of California, Riverside, Riverside, CA, USA
| | - Miriam L Diamond
- Department of Earth Sciences, University of Toronto, Toronto, ON, Canada
- School of the Environment, University of Toronto, Toronto, ON, Canada
| | | | | | - Dale Hattis
- The George Perkins Marsh Institute, Clark University, Worcester, MA, USA
| | - Russ Hauser
- Department of Environmental Health, T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Wendy Heiger-Bernays
- Department of Environmental Health, School of Public Health, Boston University, Boston, MA, USA
| | | | - Juleen Lam
- Department of Public Health, California State University, East Bay, Hayward, CA, USA
| | - Jonathan I Levy
- Department of Environmental Health, School of Public Health, Boston University, Boston, MA, USA
| | | | | | | | - Rachel Morello-Frosch
- School of Public Health, University of California, Berkeley, Berkeley, CA, USA
- Department of Environmental Science, Policy and Management, University of California, Berkeley, Berkeley, CA, USA
| | - Keeve E Nachman
- Department of Environmental Health and Engineering, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
- Johns Hopkins Risk Sciences and Public Policy Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Greylin H Nielsen
- Department of Environmental Health, School of Public Health, Boston University, Boston, MA, USA
| | - Catherine Oksas
- School of Medicine, University of California, San Francisco, CA, USA
| | - Dimitri Panagopoulos Abrahamsson
- Program On Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 490 Illinois Street, Floor 10, Box 0132, San Francisco, CA, 94143, USA
| | - Heather B Patisaul
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, USA
| | | | - Joshua F Robinson
- Program On Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 490 Illinois Street, Floor 10, Box 0132, San Francisco, CA, 94143, USA
- Center for Reproductive Sciences, Department of Obstetrics, Gynecology & Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | | | | | | | | | - Sheela Sathyanarayana
- Department of Pediatrics, University of Washington, Seattle, WA, USA
- Department of Child Health, Behavior, and Development, Seattle Children's Research Institute, Seattle, WA, USA
| | - Ted Schettler
- Science and Environmental Health Network, Ames, IA, USA
| | - Rachel M Shaffer
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, USA
| | - Bhavna Shamasunder
- Department of Urban & Environmental Policy and Public Health, Occidental College, Los Angeles, CA, USA
| | | | - Kristin Shrader-Frechette
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
- Department of Philosophy, University of Notre Dame, Notre Dame, IN, USA
| | - Gina M Solomon
- School of Medicine, University of California, San Francisco, CA, USA
- Public Health Institute, Oakland, CA, USA
| | - Wilma A Subra
- Louisiana Environmental Action Network, Baton Rouge, LA, USA
| | - Laura N Vandenberg
- Department of Environmental Health Sciences, School of Public Health & Health Sciences, University of Massachusetts, Amherst, Amherst, MA, USA
| | - Julia R Varshavsky
- Department of Health Sciences, Northeastern University, Boston, MA, USA
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Roberta F White
- Department of Environmental Health, School of Public Health, Boston University, Boston, MA, USA
| | - Ken Zarker
- Washington State Department of Ecology, Olympia, WA, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA, USA
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Abrahamsson D, Siddharth A, Robinson JF, Soshilov A, Elmore S, Cogliano V, Ng C, Khan E, Ashton R, Chiu WA, Fung J, Zeise L, Woodruff TJ. Modeling the transplacental transfer of small molecules using machine learning: a case study on per- and polyfluorinated substances (PFAS). J Expo Sci Environ Epidemiol 2022; 32:808-819. [PMID: 36207486 PMCID: PMC9742309 DOI: 10.1038/s41370-022-00481-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 05/10/2023]
Abstract
BACKGROUND Despite their large numbers and widespread use, very little is known about the extent to which per- and polyfluoroalkyl substances (PFAS) can cross the placenta and expose the developing fetus. OBJECTIVE The aim of our study is to develop a computational approach that can be used to evaluate the of extend to which small molecules, and in particular PFAS, can cross to cross the placenta and partition to cord blood. METHODS We collected experimental values of the concentration ratio between cord and maternal blood (RCM) for 260 chemical compounds and calculated their physicochemical descriptors using the cheminformatics package Mordred. We used the compiled database to, train and test an artificial neural network (ANN). And then applied the best performing model to predict RCM for a large dataset of PFAS chemicals (n = 7982). We, finally, examined the calculated physicochemical descriptors of the chemicals to identify which properties correlated significantly with RCM. RESULTS We determined that 7855 compounds were within the applicability domain and 127 compounds are outside the applicability domain of our model. Our predictions of RCM for PFAS suggested that 3623 compounds had a log RCM > 0 indicating preferable partitioning to cord blood. Some examples of these compounds were bisphenol AF, 2,2-bis(4-aminophenyl)hexafluoropropane, and nonafluoro-tert-butyl 3-methylbutyrate. SIGNIFICANCE These observations have important public health implications as many PFAS have been shown to interfere with fetal development. In addition, as these compounds are highly persistent and many of them can readily cross the placenta, they are expected to remain in the population for a long time as they are being passed from parent to offspring. IMPACT Understanding the behavior of chemicals in the human body during pregnancy is critical in preventing harmful exposures during critical periods of development. Many chemicals can cross the placenta and expose the fetus, however, the mechanism by which this transport occurs is not well understood. In our study, we developed a machine learning model that describes the transplacental transfer of chemicals as a function of their physicochemical properties. The model was then used to make predictions for a set of 7982 per- and polyfluorinated alkyl substances that are listed on EPA's CompTox Chemicals Dashboard. The model can be applied to make predictions for other chemical categories of interest, such as plasticizers and pesticides. Accurate predictions of RCM can help scientists and regulators to prioritize chemicals that have the potential to cause harm by exposing the fetus.
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Affiliation(s)
- Dimitri Abrahamsson
- Department of Obstetrics, Gynecology and Reproductive Sciences, Program on Reproductive Health and the Environment, University of California, San Francisco, 490 Illinois Street, San Francisco, CA, 94143, USA.
| | - Adi Siddharth
- Department of Obstetrics, Gynecology and Reproductive Sciences, Program on Reproductive Health and the Environment, University of California, San Francisco, 490 Illinois Street, San Francisco, CA, 94143, USA
| | - Joshua F Robinson
- Department of Obstetrics, Gynecology and Reproductive Sciences, Program on Reproductive Health and the Environment, University of California, San Francisco, 490 Illinois Street, San Francisco, CA, 94143, USA
| | - Anatoly Soshilov
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1001 I St, Sacramento, CA, 95814, USA
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1515 Clay St, Oakland, CA, 94612, USA
| | - Sarah Elmore
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1001 I St, Sacramento, CA, 95814, USA
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1515 Clay St, Oakland, CA, 94612, USA
| | - Vincent Cogliano
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1001 I St, Sacramento, CA, 95814, USA
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1515 Clay St, Oakland, CA, 94612, USA
| | - Carla Ng
- Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O'Hara St, Pittsburgh, PA, 15261, USA
| | - Elaine Khan
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1001 I St, Sacramento, CA, 95814, USA
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1515 Clay St, Oakland, CA, 94612, USA
| | - Randolph Ashton
- Wisconsin Institute for Discovery, University of Wisconsin, Madison, 330 N Orchard St, Madison, WI, 53715, USA
- The Stem Cell and Regenerative Medicine Center, University of Wisconsin, Madison, 1111 Highland Avenue, Madison, WI, 53705, USA
- Department of Biomedical Engineering, University of Wisconsin - Madison, 1550 Engineering Drive, Madison, WI, 53706, USA
| | - Weihsueh A Chiu
- Department of Veterinary Physiology and Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA
| | - Jennifer Fung
- Department of Obstetrics, Gynecology, and Reproductive Science and the Center of Reproductive Science, University of California, San Francisco, San Francisco, CA, 94143-2240, USA
| | - Lauren Zeise
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1001 I St, Sacramento, CA, 95814, USA
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, 1515 Clay St, Oakland, CA, 94612, USA
| | - Tracey J Woodruff
- Department of Obstetrics, Gynecology and Reproductive Sciences, Program on Reproductive Health and the Environment, University of California, San Francisco, 490 Illinois Street, San Francisco, CA, 94143, USA.
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Germolec DR, Lebrec H, Anderson SE, Burleson GR, Cardenas A, Corsini E, Elmore SE, Kaplan BL, Lawrence BP, Lehmann GM, Maier CC, McHale CM, Myers LP, Pallardy M, Rooney AA, Zeise L, Zhang L, Smith MT. Consensus on the Key Characteristics of Immunotoxic Agents as a Basis for Hazard Identification. Environ Health Perspect 2022; 130:105001. [PMID: 36201310 PMCID: PMC9536493 DOI: 10.1289/ehp10800] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 08/09/2022] [Accepted: 08/26/2022] [Indexed: 05/04/2023]
Abstract
BACKGROUND Key characteristics (KCs), properties of agents or exposures that confer potential hazard, have been developed for carcinogens and other toxicant classes. KCs have been used in the systematic assessment of hazards and to identify assay and data gaps that limit screening and risk assessment. Many of the mechanisms through which pharmaceuticals and occupational or environmental agents modulate immune function are well recognized. Thus KCs could be identified for immunoactive substances and applied to improve hazard assessment of immunodulatory agents. OBJECTIVES The goal was to generate a consensus-based synthesis of scientific evidence describing the KCs of agents known to cause immunotoxicity and potential applications, such as assays to measure the KCs. METHODS A committee of 18 experts with diverse specialties identified 10 KCs of immunotoxic agents, namely, 1) covalently binds to proteins to form novel antigens, 2) affects antigen processing and presentation, 3) alters immune cell signaling, 4) alters immune cell proliferation, 5) modifies cellular differentiation, 6) alters immune cell-cell communication, 7) alters effector function of specific cell types, 8) alters immune cell trafficking, 9) alters cell death processes, and 10) breaks down immune tolerance. The group considered how these KCs could influence immune processes and contribute to hypersensitivity, inappropriate enhancement, immunosuppression, or autoimmunity. DISCUSSION KCs can be used to improve efforts to identify agents that cause immunotoxicity via one or more mechanisms, to develop better testing and biomarker approaches to evaluate immunotoxicity, and to enable a more comprehensive and mechanistic understanding of adverse effects of exposures on the immune system. https://doi.org/10.1289/EHP10800.
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Affiliation(s)
- Dori R. Germolec
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Herve Lebrec
- Translational Safety & Bioanalytical Sciences, Amgen Research, South San Francisco, California, USA
| | - Stacey E. Anderson
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia, USA
| | - Gary R. Burleson
- Burleson Research Technologies, Inc., Morrisville, North Carolina, USA
| | - Andres Cardenas
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Emanuela Corsini
- Laboratory of Toxicology, Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Sarah E. Elmore
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California, USA
| | - Barbara L.F. Kaplan
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, USA
| | - B. Paige Lawrence
- Department of Environmental Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New York, USA
- Department of Microbiology & Immunology, University of Rochester School of Medicine & Dentistry, Rochester, New York, USA
| | - Geniece M. Lehmann
- Center for Public Health and Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA
| | - Curtis C. Maier
- In Vitro In Vivo Translation, Research and Development, GlaxoSmithKline, Collegeville, Pennsylvania, USA
| | - Cliona M. McHale
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - L. Peyton Myers
- Division of Pharm/Tox, Office of Infectious Diseases, Office of New Drugs, Center for Drug Evaluation and Research, U.S. Federal Food and Drug Administration, Silver Spring, Maryland, USA
| | - Marc Pallardy
- Inserm, Inflammation microbiome immunosurveillance, Université Paris-Saclay, Châtenay-Malabry, France
| | - Andrew A. Rooney
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California, USA
| | - Luoping Zhang
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Martyn T. Smith
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
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5
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Campbell MA, Iyer P, Kaufman F, Kim A, Moran F, Niknam Y, Wu L, Sandy MS, Zeise L. Animal evidence considered in determination of cannabis smoke and Δ 9 -tetrahydrocannabinol as causing reproductive toxicity (developmental endpoint); Part I. somatic development. Birth Defects Res 2022; 114:1143-1154. [PMID: 36177831 DOI: 10.1002/bdr2.2099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVES On December 11, 2019, California's Developmental and Reproductive Toxicant Identification Committee (DARTIC) met to consider the addition of cannabis smoke and Δ9 -THC to the Proposition 65 list as causing reproductive toxicity (developmental endpoint). As the lead state agency for implementing Proposition 65, the Office of Environmental Health Hazard Assessment (OEHHA) reviewed and summarized the relevant scientific literature in the form of a hazard identification document (HID). Here we provide reviews based on the HID: shortened, revised, and reformatted for a larger audience. METHODS While the HID included both human and animal data, this set of three reviews will highlight the animal-derived data pertaining to somatic development (Part I), neurodevelopmental effects (Part II), and proposed neurodevelopmental mechanisms of action (Part III). RESULTS Endogenous cannabinoids (eCBs) and their receptors serve many critical functions in normal development. Δ9 -THC can interfere with these functions. Mechanistic studies employed techniques including: blocking Δ9 -THC binding to endocannabinoid (EC) receptors, inhibiting Δ9 -THC metabolism, and/or using animals expressing knockout mutations of EC receptors. Apical somatic effects of cannabis smoke or Δ9 -THC reported in whole animal studies included decreases in offspring viability and growth. Mechanistic studies discussed in Part I focused on Δ9 -THC effects on early embryos and implantation, immune development, and bone growth. CONCLUSIONS In reaching its decision to list cannabis and Δ9 -THC as a developmental toxicant under California's Proposition 65, the DARTIC considered biological plausibility and the consistency of mechanistic information with effects reported in human and whole animal studies.
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Affiliation(s)
- Marlissa A Campbell
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Poorni Iyer
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Farla Kaufman
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Allegra Kim
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Francisco Moran
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Yassaman Niknam
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Lily Wu
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Martha S Sandy
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
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6
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Niknam Y, Iyer P, Campbell MA, Moran F, Sandy MS, Zeise L. Animal evidence considered in determination of cannabis smoke and Δ 9 -tetrahydrocannabinol as causing reproductive toxicity (developmental endpoint): Part III. Proposed neurodevelopmental mechanisms of action. Birth Defects Res 2022; 114:1169-1185. [PMID: 36125082 DOI: 10.1002/bdr2.2088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/16/2022] [Accepted: 08/28/2022] [Indexed: 11/09/2022]
Abstract
This review summarizes the most common potential pathways of neurodevelopmental toxicity due to perinatal exposure to Δ9 -tetrahydrocannabinol (Δ9 -THC) that lead to behavioral and other adverse outcomes (AOs). This is Part III in a set of reviews highlighting the animal-derived data considered by California's Developmental and Reproductive Toxicant Identification Committee (DARTIC) in 2019. The Hazard Identification Document (HID) provided to the DARTIC included a summary of human, whole animal, and mechanistic data on the neurodevelopmental toxicity of cannabis smoke and Δ9 -THC. The literature search for mechanistic data has been updated through 2020. We focus on mechanistic pathways relating to behavioral and other neurodevelopmental outcomes of perinatal exposure to Δ9 -THC. The endocannabinoid system (EC system) plays a crucial role in many processes involved in neurodevelopment and exposure to Δ9 -THC can alter these processes. Whole animal studies report changes in cognitive ability, behavior, and motor function after prenatal exposure to Δ9 -THC. Findings from mechanistic studies add to this evidence and further provide information regarding the pathways leading to these outcomes. Neuromechanistic studies can bridge the gaps between molecular initiating events and apical neurodevelopmental endpoints caused by a chemical. They offer insight into potential alterations in the same pathways by other chemicals that can also result in AOs. Studies of cannabinoid receptor agonist-induced molecular alterations and provide deep biological plausibility at the mechanistic level for the cognitive, behavioral, and motor impairments observed in animal studies after perinatal exposure to Δ9 -THC.
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Affiliation(s)
- Yassaman Niknam
- Office of Environmental Health Hazard Assessment (OEHHA)/Reproductive and Cancer Hazard Assessment Branch (RCHAB), California Environmental Protection Agency, Sacramento, California, USA
| | - Poorni Iyer
- Office of Environmental Health Hazard Assessment (OEHHA)/Reproductive and Cancer Hazard Assessment Branch (RCHAB), California Environmental Protection Agency, Sacramento, California, USA
| | - Marlissa A Campbell
- Office of Environmental Health Hazard Assessment (OEHHA)/Reproductive and Cancer Hazard Assessment Branch (RCHAB), California Environmental Protection Agency, Sacramento, California, USA
| | - Francisco Moran
- Office of Environmental Health Hazard Assessment (OEHHA)/Reproductive and Cancer Hazard Assessment Branch (RCHAB), California Environmental Protection Agency, Sacramento, California, USA
| | - Martha S Sandy
- Office of Environmental Health Hazard Assessment (OEHHA)/Reproductive and Cancer Hazard Assessment Branch (RCHAB), California Environmental Protection Agency, Sacramento, California, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment (OEHHA)/Reproductive and Cancer Hazard Assessment Branch (RCHAB), California Environmental Protection Agency, Sacramento, California, USA
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7
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Iyer P, Niknam Y, Campbell M, Moran F, Kaufman F, Kim A, Sandy M, Zeise L. Animal evidence considered in determination of cannabis smoke and
Δ
9
‐tetrahydrocannabinol (
Δ
9
‐THC
) as causing reproductive toxicity (developmental endpoint); part
II
. Neurodevelopmental effects. Birth Defects Res 2022; 114:1155-1168. [DOI: 10.1002/bdr2.2084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/19/2022] [Accepted: 08/24/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Poorni Iyer
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Yassaman Niknam
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Marlissa Campbell
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Francisco Moran
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Farla Kaufman
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Allegra Kim
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Martha Sandy
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment (OEHHA) Sacramento California USA
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8
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Lind L, Araujo JA, Barchowsky A, Belcher S, Berridge BR, Chiamvimonvat N, Chiu WA, Cogliano VJ, Elmore S, Farraj AK, Gomes AV, McHale CM, Meyer-Tamaki KB, Posnack NG, Vargas HM, Yang X, Zeise L, Zhou C, Smith MT. Key Characteristics of Cardiovascular Toxicants. Environ Health Perspect 2021; 129:95001. [PMID: 34558968 PMCID: PMC8462506 DOI: 10.1289/ehp9321] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND The concept of chemical agents having properties that confer potential hazard called key characteristics (KCs) was first developed to identify carcinogenic hazards. Identification of KCs of cardiovascular (CV) toxicants could facilitate the systematic assessment of CV hazards and understanding of assay and data gaps associated with current approaches. OBJECTIVES We sought to develop a consensus-based synthesis of scientific evidence on the KCs of chemical and nonchemical agents known to cause CV toxicity along with methods to measure them. METHODS An expert working group was convened to discuss mechanisms associated with CV toxicity. RESULTS The group identified 12 KCs of CV toxicants, defined as exogenous agents that adversely interfere with function of the CV system. The KCs were organized into those primarily affecting cardiac tissue (numbers 1-4 below), the vascular system (5-7), or both (8-12), as follows: 1) impairs regulation of cardiac excitability, 2) impairs cardiac contractility and relaxation, 3) induces cardiomyocyte injury and death, 4) induces proliferation of valve stroma, 5) impacts endothelial and vascular function, 6) alters hemostasis, 7) causes dyslipidemia, 8) impairs mitochondrial function, 9) modifies autonomic nervous system activity, 10) induces oxidative stress, 11) causes inflammation, and 12) alters hormone signaling. DISCUSSION These 12 KCs can be used to help identify pharmaceuticals and environmental pollutants as CV toxicants, as well as to better understand the mechanistic underpinnings of their toxicity. For example, evidence exists that fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] air pollution, arsenic, anthracycline drugs, and other exogenous chemicals possess one or more of the described KCs. In conclusion, the KCs could be used to identify potential CV toxicants and to define a set of test methods to evaluate CV toxicity in a more comprehensive and standardized manner than current approaches. https://doi.org/10.1289/EHP9321.
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Affiliation(s)
- Lars Lind
- Department of Medical Sciences, Clinical Epidemiology, University of Uppsala, Sweden
| | - Jesus A. Araujo
- Division of Cardiology, David Geffen School of Medicine at University of California Los Angeles (UCLA), UCLA, Los Angeles, California, USA
- Department of Environmental Health Sciences, Fielding School of Public Health and Molecular Biology Institute, UCLA, Los Angeles, California, USA
| | - Aaron Barchowsky
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pennsylvania, USA
| | - Scott Belcher
- Department of Biological Sciences, North Carolina State University, North Carolina, USA
| | - Brian R. Berridge
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Nipavan Chiamvimonvat
- Department of Internal Medicine, University of California, Davis, Davis, California, USA
| | - Weihsueh A. Chiu
- College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Vincent J. Cogliano
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Sarah Elmore
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Aimen K. Farraj
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, U.S. EPA, Research Triangle Park, North Carolina, USA
| | - Aldrin V. Gomes
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, California, USA
| | - Cliona M. McHale
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | | | - Nikki Gillum Posnack
- Children’s National Heart Institute and the Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC, USA
| | - Hugo M. Vargas
- Translational Safety & Bioanalytical Sciences, Amgen, Inc., Thousand Oaks, California, USA
| | - Xi Yang
- Division of Pharmacology and Toxicology, Office of Cardiology, Hematology, Endocrinology, and Nephrology, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Changcheng Zhou
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Martyn T. Smith
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
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9
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Rider CV, McHale CM, Webster TF, Lowe L, Goodson WH, La Merrill MA, Rice G, Zeise L, Zhang L, Smith MT. Using the Key Characteristics of Carcinogens to Develop Research on Chemical Mixtures and Cancer. Environ Health Perspect 2021; 129:35003. [PMID: 33784186 PMCID: PMC8009606 DOI: 10.1289/ehp8525] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 02/19/2021] [Accepted: 03/10/2021] [Indexed: 05/09/2023]
Abstract
BACKGROUND People are exposed to numerous chemicals throughout their lifetimes. Many of these chemicals display one or more of the key characteristics of carcinogens or interact with processes described in the hallmarks of cancer. Therefore, evaluating the effects of chemical mixtures on cancer development is an important pursuit. Challenges involved in designing research studies to evaluate the joint action of chemicals on cancer risk include the time taken to perform the experiments because of the long latency and choosing an appropriate experimental design. OBJECTIVES The objectives of this work are to present the case for developing a research program on mixtures of environmental chemicals and cancer risk and describe recommended approaches. METHODS A working group comprising the coauthors focused attention on the design of mixtures studies to inform cancer risk assessment as part of a larger effort to refine the key characteristics of carcinogens and explore their application. Working group members reviewed the key characteristics of carcinogens, hallmarks of cancer, and mixtures research for other disease end points. The group discussed options for developing tractable projects to evaluate the joint effects of environmental chemicals on cancer development. RESULTS AND DISCUSSION Three approaches for developing a research program to evaluate the effects of mixtures on cancer development were proposed: a chemical screening approach, a transgenic model-based approach, and a disease-centered approach. Advantages and disadvantages of each are discussed. https://doi.org/10.1289/EHP8525.
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Affiliation(s)
- Cynthia V. Rider
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Cliona M. McHale
- Division of Environmental Health Sciences, University of California Berkeley, School of Public Health, Berkeley, California, USA
| | - Thomas F. Webster
- Department of Environmental Health, School of Public Health, Boston University, Boston, Massachusetts, USA
| | - Leroy Lowe
- Getting to Know Cancer (NGO), Truro, Nova Scotia, Canada
| | - William H. Goodson
- Department of Surgery, California Pacific Medical Center Research Institute, San Francisco, California, USA
| | - Michele A. La Merrill
- Department of Environmental Toxicology, University of California Davis, Davis, California, USA
| | - Glenn Rice
- Office of Research & Development, Center for Public Health and Environmental Assessment, U.S. Environmental Protection Agency, Cincinnati, Ohio, USA
| | - Lauren Zeise
- Office of the Director, Office of Environmental Health and Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Luoping Zhang
- Division of Environmental Health Sciences, University of California Berkeley, School of Public Health, Berkeley, California, USA
| | - Martyn T. Smith
- Division of Environmental Health Sciences, University of California Berkeley, School of Public Health, Berkeley, California, USA
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10
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Smith MT, Guyton KZ, Kleinstreuer N, Borrel A, Cardenas A, Chiu WA, Felsher DW, Gibbons CF, Goodson WH, Houck KA, Kane AB, La Merrill MA, Lebrec H, Lowe L, McHale CM, Minocherhomji S, Rieswijk L, Sandy MS, Sone H, Wang A, Zhang L, Zeise L, Fielden M. The Key Characteristics of Carcinogens: Relationship to the Hallmarks of Cancer, Relevant Biomarkers, and Assays to Measure Them. Cancer Epidemiol Biomarkers Prev 2020; 29:1887-1903. [PMID: 32152214 PMCID: PMC7483401 DOI: 10.1158/1055-9965.epi-19-1346] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/15/2020] [Accepted: 03/04/2020] [Indexed: 12/21/2022] Open
Abstract
The key characteristics (KC) of human carcinogens provide a uniform approach to evaluating mechanistic evidence in cancer hazard identification. Refinements to the approach were requested by organizations and individuals applying the KCs. We assembled an expert committee with knowledge of carcinogenesis and experience in applying the KCs in cancer hazard identification. We leveraged this expertise and examined the literature to more clearly describe each KC, identify current and emerging assays and in vivo biomarkers that can be used to measure them, and make recommendations for future assay development. We found that the KCs are clearly distinct from the Hallmarks of Cancer, that interrelationships among the KCs can be leveraged to strengthen the KC approach (and an understanding of environmental carcinogenesis), and that the KC approach is applicable to the systematic evaluation of a broad range of potential cancer hazards in vivo and in vitro We identified gaps in coverage of the KCs by current assays. Future efforts should expand the breadth, specificity, and sensitivity of validated assays and biomarkers that can measure the 10 KCs. Refinement of the KC approach will enhance and accelerate carcinogen identification, a first step in cancer prevention.See all articles in this CEBP Focus section, "Environmental Carcinogenesis: Pathways to Prevention."
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Affiliation(s)
- Martyn T Smith
- Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, California.
| | - Kathryn Z Guyton
- Monographs Programme, International Agency for Research on Cancer, Lyon, France
| | - Nicole Kleinstreuer
- Division of Intramural Research, Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, North Carolina
- National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina
| | - Alexandre Borrel
- Division of Intramural Research, Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, North Carolina
| | - Andres Cardenas
- Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, California
| | - Weihsueh A Chiu
- Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas
| | - Dean W Felsher
- Division of Oncology, Departments of Medicine and Pathology, Stanford University School of Medicine, Stanford, California
| | - Catherine F Gibbons
- Office of Research and Development, US Environmental Protection Agency, Washington, D.C
| | - William H Goodson
- California Pacific Medical Center Research Institute, San Francisco, California
| | - Keith A Houck
- Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, North Carolina
| | - Agnes B Kane
- Department of Pathology and Laboratory Medicine, Alpert Medical School, Brown University, Providence, Rhode Island
| | - Michele A La Merrill
- Department of Environmental Toxicology, University of California, Davis, California
| | - Herve Lebrec
- Comparative Biology & Safety Sciences, Amgen Research, Amgen Inc., Thousand Oaks, California
| | - Leroy Lowe
- Getting to Know Cancer, Truro, Nova Scotia, Canada
| | - Cliona M McHale
- Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, California
| | - Sheroy Minocherhomji
- Comparative Biology & Safety Sciences, Amgen Research, Amgen Inc., Thousand Oaks, California
| | - Linda Rieswijk
- Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, California
- Institute of Data Science, Maastricht University, Maastricht, the Netherlands
| | - Martha S Sandy
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California
| | - Hideko Sone
- Yokohama University of Pharmacy and National Institute for Environmental Studies, Tsukuba Ibaraki, Japan
| | - Amy Wang
- Office of the Report on Carcinogens, Division of National Toxicology Program, The National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina
| | - Luoping Zhang
- Division of Environmental Health Sciences, School of Public Health, University of California Berkeley, Berkeley, California
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California
| | - Mark Fielden
- Expansion Therapeutics Inc, San Diego, California
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11
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La Merrill MA, Vandenberg LN, Smith MT, Goodson W, Browne P, Patisaul HB, Guyton KZ, Kortenkamp A, Cogliano VJ, Woodruff TJ, Rieswijk L, Sone H, Korach KS, Gore AC, Zeise L, Zoeller RT. Consensus on the key characteristics of endocrine-disrupting chemicals as a basis for hazard identification. Nat Rev Endocrinol 2020; 16:45-57. [PMID: 31719706 PMCID: PMC6902641 DOI: 10.1038/s41574-019-0273-8] [Citation(s) in RCA: 356] [Impact Index Per Article: 89.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/02/2019] [Indexed: 12/11/2022]
Abstract
Endocrine-disrupting chemicals (EDCs) are exogenous chemicals that interfere with hormone action, thereby increasing the risk of adverse health outcomes, including cancer, reproductive impairment, cognitive deficits and obesity. A complex literature of mechanistic studies provides evidence on the hazards of EDC exposure, yet there is no widely accepted systematic method to integrate these data to help identify EDC hazards. Inspired by work to improve hazard identification of carcinogens using key characteristics (KCs), we have developed ten KCs of EDCs based on our knowledge of hormone actions and EDC effects. In this Expert Consensus Statement, we describe the logic by which these KCs are identified and the assays that could be used to assess several of these KCs. We reflect on how these ten KCs can be used to identify, organize and utilize mechanistic data when evaluating chemicals as EDCs, and we use diethylstilbestrol, bisphenol A and perchlorate as examples to illustrate this approach.
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Affiliation(s)
- Michele A La Merrill
- Department of Environmental Toxicology, University of California, Davis, CA, USA.
| | - Laura N Vandenberg
- Department of Environmental Health Science, School of Public Health and Health Sciences, University of Masschusetts, Amherst, MA, USA
| | - Martyn T Smith
- School of Public Health, University of California, Berkeley, CA, USA
| | - William Goodson
- California Pacific Medical Center Research Institute, Sutter Hospital, San Francisco, CA, USA
| | - Patience Browne
- Environmental Directorate, Organisation for Economic Co-operation and Development, Paris, France
| | - Heather B Patisaul
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Kathryn Z Guyton
- International Agency for Research on Cancer, World Health Organization, Lyon, France
| | | | - Vincent J Cogliano
- Office of the Science Advisor, United States Environmental Protection Agency, Washington, DC, USA
| | - Tracey J Woodruff
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Linda Rieswijk
- School of Public Health, University of California, Berkeley, CA, USA
- Institute of Data Science, Maastricht University, Maastricht, Netherlands
| | - Hideko Sone
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Ibaraki, Japan
| | - Kenneth S Korach
- Receptor Biology, Section Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Science, Durham, NC, USA
| | - Andrea C Gore
- Division of Pharmacology and Toxicology, University of Texas at Austin, Austin, TX, USA
| | - Lauren Zeise
- Office of the Director, Office of Environmental Health Hazard Assessment of the California Environmental Protection Agency, Sacramento, CA, USA
| | - R Thomas Zoeller
- Biology Department, University of Masschusetts, Amherst, MA, USA
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12
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Luderer U, Eskenazi B, Hauser R, Korach KS, McHale CM, Moran F, Rieswijk L, Solomon G, Udagawa O, Zhang L, Zlatnik M, Zeise L, Smith MT. Proposed Key Characteristics of Female Reproductive Toxicants as an Approach for Organizing and Evaluating Mechanistic Data in Hazard Assessment. Environ Health Perspect 2019; 127:75001. [PMID: 31322437 PMCID: PMC6791466 DOI: 10.1289/ehp4971] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
BACKGROUND Identification of female reproductive toxicants is currently based largely on integrated epidemiological and in vivo toxicology data and, to a lesser degree, on mechanistic data. A uniform approach to systematically search, organize, integrate, and evaluate mechanistic evidence of female reproductive toxicity from various data types is lacking. OBJECTIVE We sought to apply a key characteristics approach similar to that pioneered for carcinogen hazard identification to female reproductive toxicant hazard identification. METHODS A working group of international experts was convened to discuss mechanisms associated with chemical-induced female reproductive toxicity and identified 10 key characteristics of chemicals that cause female reproductive toxicity: 1) alters hormone receptor signaling; alters reproductive hormone production, secretion, or metabolism; 2) chemical or metabolite is genotoxic; 3) induces epigenetic alterations; 4) causes mitochondrial dysfunction; 5) induces oxidative stress; 6) alters immune function; 7) alters cell signal transduction; 8) alters direct cell–cell interactions; 9) alters survival, proliferation, cell death, or metabolic pathways; and 10) alters microtubules and associated structures. As proof of principle, cyclophosphamide and diethylstilbestrol (DES), for which both human and animal studies have demonstrated female reproductive toxicity, display at least 5 and 3 key characteristics, respectively. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), for which the epidemiological evidence is mixed, exhibits 5 key characteristics. DISCUSSION Future efforts should focus on evaluating the proposed key characteristics against additional known and suspected female reproductive toxicants. Chemicals that exhibit one or more of the key characteristics could be prioritized for additional evaluation and testing. A key characteristics approach has the potential to integrate with pathway-based toxicity testing to improve prediction of female reproductive toxicity in chemicals and potentially prevent some toxicants from entering common use. https://doi.org/10.1289/EHP4971.
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Affiliation(s)
- Ulrike Luderer
- Center for Occupational and Environmental Health, University of California, Irvine, Irvine, California, USA
| | - Brenda Eskenazi
- School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Russ Hauser
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Kenneth S. Korach
- National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Cliona M. McHale
- School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Francisco Moran
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Linda Rieswijk
- School of Public Health, University of California, Berkeley, Berkeley, California, USA
- Institute of Data Science, Maastricht University, Maastricht, Netherlands
| | - Gina Solomon
- Department of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Osamu Udagawa
- Center for Health and Environmental Risk Research, National Institute of Environmental Studies, Tsukuba-City, Ibaraki, Japan
| | - Luoping Zhang
- School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Marya Zlatnik
- Department of Obstetrics and Gynecology, University of California, San Francisco, San Francisco, California, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Martyn T. Smith
- School of Public Health, University of California, Berkeley, Berkeley, California, USA
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13
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Marques MM, Berrington de Gonzalez A, Beland FA, Browne P, Demers PA, Lachenmeier DW, Bahadori T, Barupal DK, Belpoggi F, Comba P, Dai M, Daniels RD, Ferreccio C, Grigoriev OA, Hong YC, Hoover RN, Kanno J, Kogevinas M, Lasfargues G, Malekzadeh R, Masten S, Newton R, Norat T, Pappas JJ, Queiroz Moreira C, Rodríguez T, Rodríguez-Guzmán J, Sewram V, Zeise L, Benbrahim-Tallaa L, Bouvard V, Cree IA, El Ghissassi F, Girschik J, Grosse Y, Hall AL, Turner MC, Straif K, Korenjak M, McCormack V, Müller K, Schüz J, Zavadil J, Schubauer-Berigan MK, Guyton KZ. Advisory Group recommendations on priorities for the IARC Monographs. Lancet Oncol 2019; 20:763-764. [DOI: 10.1016/s1470-2045(19)30246-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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14
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Arzuaga X, Smith MT, Gibbons CF, Skakkebæk NE, Yost EE, Beverly BEJ, Hotchkiss AK, Hauser R, Pagani RL, Schrader SM, Zeise L, Prins GS. Proposed Key Characteristics of Male Reproductive Toxicants as an Approach for Organizing and Evaluating Mechanistic Evidence in Human Health Hazard Assessments. Environ Health Perspect 2019; 127:65001. [PMID: 31199676 PMCID: PMC6792367 DOI: 10.1289/ehp5045] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 05/22/2019] [Accepted: 05/30/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND Assessing chemicals for their potential to cause male reproductive toxicity involves the evaluation of evidence obtained from experimental, epidemiological, and mechanistic studies. Although mechanistic evidence plays an important role in hazard identification and evidence integration, the process of identifying, screening and analyzing mechanistic studies and outcomes is a challenging exercise due to the diversity of research models and methods and the variety of known and proposed pathways for chemical-induced toxicity. Ten key characteristics of carcinogens provide a valuable tool for organizing and assessing chemical-specific data by potential mechanisms for cancer-causing agents. However, such an approach has not yet been developed for noncancer adverse outcomes. OBJECTIVES The objective in this study was to identify a set of key characteristics that are frequently exhibited by exogenous agents that cause male reproductive toxicity and that could be applied for identifying, organizing, and summarizing mechanistic evidence related to this outcome. DISCUSSION The identification of eight key characteristics of male reproductive toxicants was based on a survey of known male reproductive toxicants and established mechanisms and pathways of toxicity. The eight key characteristics can provide a basis for the systematic, transparent, and objective organization of mechanistic evidence relevant to chemical-induced effects on the male reproductive system. https://doi.org/10.1289/EHP5045.
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Affiliation(s)
- Xabier Arzuaga
- National Center for Environmental Assessment, U.S. Environmental Protection Agency, Washington, DC, USA
| | - Martyn T. Smith
- University of California, Berkeley, School of Public Health, Berkeley, California, USA
| | - Catherine F. Gibbons
- National Center for Environmental Assessment, U.S. Environmental Protection Agency, Washington, DC, USA
| | - Niels E. Skakkebæk
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Erin E. Yost
- National Center for Environmental Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Brandiese E. J. Beverly
- Office of Health Assessment and Translation, National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Andrew K. Hotchkiss
- National Center for Environmental Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Russ Hauser
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Rodrigo L. Pagani
- Department of Urology, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Steven M. Schrader
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, Ohio, USA (retired)
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA
| | - Gail S. Prins
- Department of Urology, University of Illinois at Chicago, Chicago, Illinois, USA
- School of Public Health, University of Illinois at Chicago, Chicago, Illinois, USA
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Iyer S, Pham N, Marty M, Sandy M, Solomon G, Zeise L. An Integrated Approach Using Publicly Available Resources for Identifying and Characterizing Chemicals of Potential Toxicity Concern: Proof-of-Concept With Chemicals That Affect Cancer Pathways. Toxicol Sci 2019; 169:14-24. [DOI: 10.1093/toxsci/kfz017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Shoba Iyer
- Office of Environmental Health Hazard Assessment (OEHHA), California Environmental Protection Agency’s (CalEPA’s), Oakland, California
| | - Nathalie Pham
- Office of Environmental Health Hazard Assessment (OEHHA), California Environmental Protection Agency’s (CalEPA’s), Sacramento, California
| | - Melanie Marty
- Office of Environmental Health Hazard Assessment (OEHHA), California Environmental Protection Agency’s (CalEPA’s), Sacramento, California
| | - Martha Sandy
- Office of Environmental Health Hazard Assessment (OEHHA), California Environmental Protection Agency’s (CalEPA’s), Oakland, California
| | - Gina Solomon
- Department of Medicine, University of California, San Francisco (UCSF), San Francisco, California
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment (OEHHA), California Environmental Protection Agency’s (CalEPA’s), Oakland, California
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McHale CM, Osborne G, Morello-Frosch R, Salmon AG, Sandy MS, Solomon G, Zhang L, Smith MT, Zeise L. Assessing health risks from multiple environmental stressors: Moving from G×E to I×E. Mutat Res Rev Mutat Res 2017; 775:11-20. [PMID: 29555026 DOI: 10.1016/j.mrrev.2017.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 02/06/2023]
Abstract
Research on disease causation often attempts to isolate the effects of individual factors, including individual genes or environmental factors. This reductionist approach has generated many discoveries, but misses important interactive and cumulative effects that may help explain the broad range of variability in disease occurrence observed across studies and individuals. A disease rarely results from a single factor, and instead results from a broader combination of factors, characterized here as intrinsic (I) and extrinsic (E) factors. Intrinsic vulnerability or resilience emanates from a variety of both fixed and shifting biological factors including genetic traits, while extrinsic factors comprise all biologically-relevant external stressors encountered across the lifespan. The I×E concept incorporates the multi-factorial and dynamic nature of health and disease and provides a unified, conceptual basis for integrating results from multiple areas of research, including genomics, G×E, developmental origins of health and disease, and the exposome. We describe the utility of the I×E concept to better understand and characterize the cumulative impact of multiple extrinsic and intrinsic factors on individual and population health. New research methods increasingly facilitate the measurement of multifactorial and interactive effects in epidemiological and toxicological studies. Tiered or indicator-based approaches can guide the selection of potentially relevant I and E factors for study and quantification, and exposomics methods may eventually produce results that can be used to generate a response function over the life course. Quantitative data on I×E interactive effects should generate a better understanding of the variability in human response to environmental factors. The proposed I×E concept highlights the role for broader study design in order to identify extrinsic and intrinsic factors amenable to interventions at the individual and population levels in order to enhance resilience, reduce vulnerability and improve health.
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Affiliation(s)
- Cliona M McHale
- Superfund Research Center, School of Public Health, University of California, Berkeley, CA 94720, USA.
| | - Gwendolyn Osborne
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA 94612, USA
| | - Rachel Morello-Frosch
- Superfund Research Center, School of Public Health, University of California, Berkeley, CA 94720, USA; Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720, USA
| | - Andrew G Salmon
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA 94612, USA
| | - Martha S Sandy
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA 94612, USA
| | - Gina Solomon
- California Environmental Protection Agency, Sacramento, CA 95814, USA
| | - Luoping Zhang
- Superfund Research Center, School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Martyn T Smith
- Superfund Research Center, School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA 94612, USA
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Vesterinen HM, Morello-Frosch R, Sen S, Zeise L, Woodruff TJ. Cumulative effects of prenatal-exposure to exogenous chemicals and psychosocial stress on fetal growth: Systematic-review of the human and animal evidence. PLoS One 2017; 12:e0176331. [PMID: 28700705 PMCID: PMC5507491 DOI: 10.1371/journal.pone.0176331] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/14/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Adverse effects of prenatal stress or environmental chemical exposures on fetal growth are well described, yet their combined effect remains unclear. OBJECTIVES To conduct a systematic review on the combined impact and interaction of prenatal exposure to stress and chemicals on developmental outcomes. METHODS We used the first three steps of the Navigation Guide systematic review. We wrote a protocol, performed a robust literature search to identify relevant animal and human studies and extracted data on developmental outcomes. For the most common outcome (fetal growth), we evaluated risk of bias, calculated effect sizes for main effects of individual and combined exposures, and performed a random effects meta-analysis of those studies reporting on odds of low birthweight (LBW) by smoking and socioeconomic status (SES). RESULTS We identified 17 human- and 22 animal-studies of combined chemical and stress exposures and fetal growth. Human studies tended to have a lower risk of bias across nine domains. Generally, we found stronger effects for chemicals than stress, and these exposures were associated with reduced fetal growth in the low-stress group and the association was often greater in high stress groups, with limited evidence of effect modification. We found smoking associated with significantly increased odds of LBW, with a greater effect for high stress (low SES; OR 4.75 (2.46-9.16)) compared to low stress (high SES; OR 1.95 (95% CI 1.53-2.48)). Animal studies generally had a high risk of bias with no significant combined effect or effect modification. CONCLUSIONS We found that despite concern for the combined effects of environmental chemicals and stress, this is still an under-studied topic, though limited available human studies indicate chemical exposures exert stronger effects than stress, and this effect is generally larger in the presence of stress.
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Affiliation(s)
- Hanna M. Vesterinen
- Program on Reproductive Health and the Environment, University of California, San Francisco, United States of America
| | - Rachel Morello-Frosch
- Department of Environmental Science, Policy and Management and School of Public Health, University of California, Berkeley, United States of America
| | - Saunak Sen
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, United States of America
| | - Lauren Zeise
- California Environmental Protection Agency Office of Environmental Health Hazard Assessment, Oakland, United States of America
| | - Tracey J. Woodruff
- Program on Reproductive Health and the Environment, University of California, San Francisco, United States of America
- * E-mail:
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Abstract
Regulatory agencies face daunting challenges identifying emerging chemical hazards because of the large number of chemicals in commerce and limited data on exposure and toxicology. Evaluating one chemical at a time is inefficient and can lead to replacement with uncharacterized chemicals or chemicals with structural features already linked to toxicity. The Office of Environmental Health Hazard Assessment (OEHHA) has developed a process for constructing and assessing chemical groups for potential biomonitoring in California. We screen for chemicals with significant exposure potential and propose possible chemical groups, based on structure and function. To support formal consideration of these groups by Biomonitoring California’s Scientific Guidance Panel, we conduct a detailed review of exposure and toxicity data and examine the likelihood of detection in biological samples. To date, 12 chemical groups have been constructed and added to the pool of chemicals that can be selected for Biomonitoring California studies, including p,p´-bisphenols, brominated and chlorinated organic compounds used as flame retardants, non-halogenated aromatic phosphates, and synthetic polycyclic musks. Evaluating chemical groups, rather than individual chemicals, is an efficient way to respond to shifts in chemical use and the emergence of new chemicals. This strategy can enable earlier identification of important chemicals for monitoring and intervention.
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Affiliation(s)
- Gail Krowech
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Sara Hoover
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Laurel Plummer
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Martha Sandy
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Gina Solomon
- California Environmental Protection Agency, Sacramento, California, USA
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19
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Cote I, Andersen ME, Ankley GT, Barone S, Birnbaum LS, Boekelheide K, Bois FY, Burgoon LD, Chiu WA, Crawford-Brown D, Crofton KM, DeVito M, Devlin RB, Edwards SW, Guyton KZ, Hattis D, Judson RS, Knight D, Krewski D, Lambert J, Maull EA, Mendrick D, Paoli GM, Patel CJ, Perkins EJ, Poje G, Portier CJ, Rusyn I, Schulte PA, Simeonov A, Smith MT, Thayer KA, Thomas RS, Thomas R, Tice RR, Vandenberg JJ, Villeneuve DL, Wesselkamper S, Whelan M, Whittaker C, White R, Xia M, Yauk C, Zeise L, Zhao J, DeWoskin RS. The Next Generation of Risk Assessment Multi-Year Study-Highlights of Findings, Applications to Risk Assessment, and Future Directions. Environ Health Perspect 2016; 124:1671-1682. [PMID: 27091369 PMCID: PMC5089888 DOI: 10.1289/ehp233] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 10/30/2015] [Accepted: 03/29/2016] [Indexed: 05/19/2023]
Abstract
BACKGROUND The Next Generation (NexGen) of Risk Assessment effort is a multi-year collaboration among several organizations evaluating new, potentially more efficient molecular, computational, and systems biology approaches to risk assessment. This article summarizes our findings, suggests applications to risk assessment, and identifies strategic research directions. OBJECTIVE Our specific objectives were to test whether advanced biological data and methods could better inform our understanding of public health risks posed by environmental exposures. METHODS New data and methods were applied and evaluated for use in hazard identification and dose-response assessment. Biomarkers of exposure and effect, and risk characterization were also examined. Consideration was given to various decision contexts with increasing regulatory and public health impacts. Data types included transcriptomics, genomics, and proteomics. Methods included molecular epidemiology and clinical studies, bioinformatic knowledge mining, pathway and network analyses, short-duration in vivo and in vitro bioassays, and quantitative structure activity relationship modeling. DISCUSSION NexGen has advanced our ability to apply new science by more rapidly identifying chemicals and exposures of potential concern, helping characterize mechanisms of action that influence conclusions about causality, exposure-response relationships, susceptibility and cumulative risk, and by elucidating new biomarkers of exposure and effects. Additionally, NexGen has fostered extensive discussion among risk scientists and managers and improved confidence in interpreting and applying new data streams. CONCLUSIONS While considerable uncertainties remain, thoughtful application of new knowledge to risk assessment appears reasonable for augmenting major scope assessments, forming the basis for or augmenting limited scope assessments, and for prioritization and screening of very data limited chemicals. Citation: Cote I, Andersen ME, Ankley GT, Barone S, Birnbaum LS, Boekelheide K, Bois FY, Burgoon LD, Chiu WA, Crawford-Brown D, Crofton KM, DeVito M, Devlin RB, Edwards SW, Guyton KZ, Hattis D, Judson RS, Knight D, Krewski D, Lambert J, Maull EA, Mendrick D, Paoli GM, Patel CJ, Perkins EJ, Poje G, Portier CJ, Rusyn I, Schulte PA, Simeonov A, Smith MT, Thayer KA, Thomas RS, Thomas R, Tice RR, Vandenberg JJ, Villeneuve DL, Wesselkamper S, Whelan M, Whittaker C, White R, Xia M, Yauk C, Zeise L, Zhao J, DeWoskin RS. 2016. The Next Generation of Risk Assessment multiyear study-highlights of findings, applications to risk assessment, and future directions. Environ Health Perspect 124:1671-1682; http://dx.doi.org/10.1289/EHP233.
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Affiliation(s)
- Ila Cote
- National Center for Environmental Assessment, U.S. Environmental Protection Agency (EPA), Washington, District of Columbia, USA
- Address correspondence to I. Cote, U.S. Environmental Protection Agency, Region 8, Room 8152, 1595 Wynkoop St., Denver, CO 80202-1129 USA. Telephone: (202) 288-9539. E-mail:
| | | | - Gerald T. Ankley
- National Health and Environmental Effects Research Laboratory, U.S. EPA, Duluth, Minnesota, USA
| | - Stanley Barone
- Office of Chemical Safety and Pollution Prevention, U.S. EPA, Washington, District of Columbia, USA
| | - Linda S. Birnbaum
- National Institute of Environmental Health Sciences, and
- National Toxicology Program, National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina, USA
| | - Kim Boekelheide
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Frederic Y. Bois
- Unité Modèles pour l’Écotoxicologie et la Toxicologie, Institut National de l’Environnement Industriel et des Risques, Verneuil en Halatte, France
| | - Lyle D. Burgoon
- U.S. Army Engineer Research and Development Center, Research Triangle Park, North Carolina, USA
| | - Weihsueh A. Chiu
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | | | | | - Michael DeVito
- National Institute of Environmental Health Sciences, and
- National Toxicology Program, National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina, USA
| | - Robert B. Devlin
- National Health and Environmental Effects Research Laboratory, U.S. EPA, Research Triangle Park, North Carolina, USA
| | - Stephen W. Edwards
- National Health and Environmental Effects Research Laboratory, U.S. EPA, Research Triangle Park, North Carolina, USA
| | | | - Dale Hattis
- George Perkins Marsh Institute, Clark University, Worcester, Massachusetts, USA
| | | | - Derek Knight
- European Chemicals Agency, Annankatu, Helsinki, Finland
| | - Daniel Krewski
- McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Ontario, Canada
| | - Jason Lambert
- National Center for Environmental Assessment, U.S. EPA, Cincinnati, Ohio, USA
| | - Elizabeth Anne Maull
- National Institute of Environmental Health Sciences, and
- National Toxicology Program, National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina, USA
| | - Donna Mendrick
- National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas, USA
| | | | - Chirag Jagdish Patel
- Department of Biomedical Informatics, Harvard Medical School, Boston, Massachusetts, USA
| | - Edward J. Perkins
- U.S. Army Engineer Research and Development Center, Vicksburg, Mississippi, USA
| | - Gerald Poje
- Grant Consulting Group, Washington, District of Columbia, USA
| | | | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Paul A. Schulte
- Education and Information Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, Ohio, USA
| | - Anton Simeonov
- National Center for Advancing Translational Sciences, NIH, DHHS, Bethesda, Maryland, USA
| | - Martyn T. Smith
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Kristina A. Thayer
- National Institute of Environmental Health Sciences, and
- National Toxicology Program, National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina, USA
| | | | - Reuben Thomas
- Gladstone Institutes, University of California, San Francisco, San Francisco, California, USA
| | - Raymond R. Tice
- National Institute of Environmental Health Sciences, and
- National Toxicology Program, National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina, USA
| | - John J. Vandenberg
- National Center for Environmental Assessment, U.S. Environmental Protection Agency (EPA), Washington, District of Columbia, USA
| | - Daniel L. Villeneuve
- National Health and Environmental Effects Research Laboratory, U.S. EPA, Duluth, Minnesota, USA
| | - Scott Wesselkamper
- National Center for Environmental Assessment, U.S. EPA, Cincinnati, Ohio, USA
| | - Maurice Whelan
- Systems Toxicology Unit, European Commission Joint Research Centre, Ispra, Italy
| | - Christine Whittaker
- Education and Information Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, Ohio, USA
| | - Ronald White
- Center for Effective Government, Washington, District of Columbia, USA
| | - Menghang Xia
- National Center for Advancing Translational Sciences, NIH, DHHS, Bethesda, Maryland, USA
| | - Carole Yauk
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California EPA, Oakland, California, USA
| | - Jay Zhao
- National Center for Environmental Assessment, U.S. EPA, Cincinnati, Ohio, USA
| | - Robert S. DeWoskin
- National Center for Environmental Assessment, U.S. Environmental Protection Agency (EPA), Washington, District of Columbia, USA
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20
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Abstract
Carcinogenic response is compared to noncarcinogenic toxicity in that group of chemicals tested by the National Cancer Institute (NCI) and National Toxicology Program (NTP) between 1976 and 1982 and reported in the Carcinogenesis Technical Report Series. A positive finding of carcinogenicity in the bioassay is correlated with the degree of noncarcinogenic chronic toxicity of the dose applied. Comparisons of acute toxicity (LD50) with carcinogenic potency show that they are correlated, but the correlation may in part be an artifact, since doses used in the NCI/NTP carcinogenesis bioassays are toxic and because reliable measures of potency can only be derived for positive carcinogenic responses. The high correlations for certain classes of chemicals and the relationship of chronic toxicity to positive carcinogenic finding suggest that these relationships are more than spurious. Since toxicities in different species are highly correlated, these findings imply that carcinogenicities in different species are also correlated.
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Affiliation(s)
- L. Zeise
- Harvard University Jefferson 266 Cambridge, MA 02138
| | | | - R. Wilson
- Harvard University Jefferson 266 Cambridge, MA 02138
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21
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Johnson PI, Koustas E, Vesterinen HM, Sutton P, Atchley DS, Kim AN, Campbell M, Donald JM, Sen S, Bero L, Zeise L, Woodruff TJ. Application of the Navigation Guide systematic review methodology to the evidence for developmental and reproductive toxicity of triclosan. Environ Int 2016; 92-93:716-28. [PMID: 27156197 PMCID: PMC4951161 DOI: 10.1016/j.envint.2016.03.009] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 03/08/2016] [Accepted: 03/09/2016] [Indexed: 05/19/2023]
Abstract
BACKGROUND There are reports of developmental and reproductive health effects associated with the widely used biocide triclosan. OBJECTIVE Apply the Navigation Guide systematic review methodology to answer the question: Does exposure to triclosan have adverse effects on human development or reproduction? METHODS We applied the first 3 steps of the Navigation Guide methodology: 1) Specify a study question, 2) Select the evidence, and 3) Rate quality and strength of the evidence. We developed a protocol, conducted a comprehensive search of the literature, and identified relevant studies using pre-specified criteria. We assessed the number and type of all relevant studies. We evaluated each included study for risk of bias and rated the quality and strength of the evidence for the selected outcomes. We conducted a meta-analysis on a subset of suitable data. RESULTS We found 4282 potentially relevant records, and 81 records met our inclusion criteria. Of the more than 100 endpoints identified by our search, we focused our evaluation on hormone concentration outcomes, which had the largest human and non-human mammalian data set. Three human studies and 8 studies conducted in rats reported thyroxine levels as outcomes. The rat data were amenable to meta-analysis. Because only one of the human thyroxine studies quantified exposure, we did not conduct a meta-analysis of the human data. Through meta-analysis of the data for rats, we estimated for prenatal exposure a 0.09% (95% CI: -0.20, 0.02) reduction in thyroxine concentration per mg triclosan/kg-bw in fetal and young rats compared to control. For postnatal exposure we estimated a 0.31% (95% CI: -0.38, -0.23) reduction in thyroxine per mg triclosan/kg-bw, also compared to control. Overall, we found low to moderate risk of bias across the human studies and moderate to high risk of bias across the non-human studies, and assigned a "moderate/low" quality rating to the body of evidence for human thyroid hormone alterations and a "moderate" quality rating to the body of evidence for non-human thyroid hormone alterations. CONCLUSION Based on this application of the Navigation Guide systematic review methodology, we concluded that there was "sufficient" non-human evidence and "inadequate" human evidence of an association between triclosan exposure and thyroxine concentrations, and consequently, triclosan is "possibly toxic" to reproductive and developmental health. Thyroid hormone disruption is an upstream indicator of developmental toxicity. Additional endpoints may be identified as being of equal or greater concern as other data are developed or evaluated.
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Affiliation(s)
- Paula I Johnson
- University of California San Francisco, Program on Reproductive Health and the Environment, Oakland, CA, USA.
| | - Erica Koustas
- ORISE Post-doctoral Fellowship, U.S. Environmental Protection Agency, Office of Policy, National Center for Environmental Economics, Washington, D.C., USA
| | - Hanna M Vesterinen
- University of California San Francisco, Program on Reproductive Health and the Environment, Oakland, CA, USA
| | - Patrice Sutton
- University of California San Francisco, Program on Reproductive Health and the Environment, Oakland, CA, USA
| | - Dylan S Atchley
- University of California San Francisco, Program on Reproductive Health and the Environment, Oakland, CA, USA
| | - Allegra N Kim
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, CA, USA
| | - Marlissa Campbell
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, CA, USA
| | - James M Donald
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, CA, USA
| | - Saunak Sen
- University of California San Francisco, Department of Epidemiology and Biostatistics, San Francisco, CA, USA
| | - Lisa Bero
- University of California San Francisco, Department of Clinical Pharmacy, San Francisco, CA, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, CA, USA
| | - Tracey J Woodruff
- University of California San Francisco, Program on Reproductive Health and the Environment, Oakland, CA, USA
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22
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Pham N, Iyer S, Hackett E, Lock BH, Sandy M, Zeise L, Solomon G, Marty M. Using ToxCast to Explore Chemical Activities and Hazard Traits: A Case Study WithOrtho-Phthalates. Toxicol Sci 2016; 151:286-301. [DOI: 10.1093/toxsci/kfw049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Abstract
Many communities are located near multiple sources of pollution, including current and former industrial sites, major roadways, and agricultural operations. Populations in such locations are predominantly low-income, with a large percentage of minorities and non-English speakers. These communities face challenges that can affect the health of their residents, including limited access to health care, a shortage of grocery stores, poor housing quality, and a lack of parks and open spaces. Environmental exposures may interact with social stressors, thereby worsening health outcomes. Age, genetic characteristics, and preexisting health conditions increase the risk of adverse health effects from exposure to pollutants. There are existing approaches for characterizing cumulative exposures, cumulative risks, and cumulative health impacts. Although such approaches have merit, they also have significant constraints. New developments in exposure monitoring, mapping, toxicology, and epidemiology, especially when informed by community participation, have the potential to advance the science on cumulative impacts and to improve decision making.
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Affiliation(s)
- Gina M Solomon
- Office of the Secretary, California Environmental Protection Agency (CalEPA), Sacramento, California 95812;
| | - Rachel Morello-Frosch
- Department of Environmental Science, Policy and Management and School of Public Health, University of California, Berkeley, California 94720-3114;
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (CalEPA), Oakland, California 94612; ,
| | - John B Faust
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (CalEPA), Oakland, California 94612; ,
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24
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Schwarzman MR, Ackerman JM, Dairkee SH, Fenton SE, Johnson D, Navarro KM, Osborne G, Rudel RA, Solomon GM, Zeise L, Janssen S. Screening for Chemical Contributions to Breast Cancer Risk: A Case Study for Chemical Safety Evaluation. Environ Health Perspect 2015; 123:1255-64. [PMID: 26032647 PMCID: PMC4671249 DOI: 10.1289/ehp.1408337] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/20/2015] [Indexed: 05/10/2023]
Abstract
BACKGROUND Current approaches to chemical screening, prioritization, and assessment are being reenvisioned, driven by innovations in chemical safety testing, new chemical regulations, and demand for information on human and environmental impacts of chemicals. To conceptualize these changes through the lens of a prevalent disease, the Breast Cancer and Chemicals Policy project convened an interdisciplinary expert panel to investigate methods for identifying chemicals that may increase breast cancer risk. METHODS Based on a review of current evidence, the panel identified key biological processes whose perturbation may alter breast cancer risk. We identified corresponding assays to develop the Hazard Identification Approach for Breast Carcinogens (HIA-BC), a method for detecting chemicals that may raise breast cancer risk. Finally, we conducted a literature-based pilot test of the HIA-BC. RESULTS The HIA-BC identifies assays capable of detecting alterations to biological processes relevant to breast cancer, including cellular and molecular events, tissue changes, and factors that alter susceptibility. In the pilot test of the HIA-BC, chemicals associated with breast cancer all demonstrated genotoxic or endocrine activity, but not necessarily both. Significant data gaps persist. CONCLUSIONS This approach could inform the development of toxicity testing that targets mechanisms relevant to breast cancer, providing a basis for identifying safer chemicals. The study identified important end points not currently evaluated by federal testing programs, including altered mammary gland development, Her2 activation, progesterone receptor activity, prolactin effects, and aspects of estrogen receptor β activity. This approach could be extended to identify the biological processes and screening methods relevant for other common diseases.
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Affiliation(s)
- Megan R Schwarzman
- Center for Occupational and Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA
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25
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Silva M, Pham N, Lewis C, Iyer S, Kwok E, Solomon G, Zeise L. A Comparison of ToxCast Test Results with In Vivo and Other In Vitro Endpoints for Neuro, Endocrine, and Developmental Toxicities: A Case Study Using Endosulfan and Methidathion. ACTA ACUST UNITED AC 2015; 104:71-89. [PMID: 26017137 DOI: 10.1002/bdrb.21140] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/27/2015] [Indexed: 11/10/2022]
Abstract
INTRODUCTION The U.S. Environmental Protection Agency's (EPA's) Toxicity Forecaster (ToxCast) is a potential tool for chemical prioritization, hazard identification, and risk assessment. We conducted a case study to compare ToxCast data with endpoints from other in vitro and in vivo studies for two data-rich pesticides: endosulfan and methidathion. METHODS ToxCast assays for endocrine disruption, development (zebrafish), and neurotoxicity were qualitatively compared to traditional neurotoxicity, developmental and reproductive toxicity findings. We also used in vitro-in vivo extrapolation to convert half-maximal activity concentrations in active ToxCast assays to rat oral equivalent doses, and quantitatively compared these to the lowest observable effect level (LOEL) from in vivo studies. RESULTS Endosulfan was inactive for GABAA R, unlike in vivo; but active with dopamine transporter assays and was neurotoxic in zebrafish as expected. Methidathion was not active for these endpoints in vivo or in vitro. Acetylcholinesterase inhibition was ToxCast-inactive, although both pesticides are inhibitors in vivo. ToxCast results were generally inactive for endosulfan estrogen receptor agonism and androgen receptor antagonism unlike in vivo. Calculated oral equivalent doses for estrogen receptor and androgen receptor pathways and for zebrafish assays for both compounds were generally consistent with in vivo LOELs. Endosulfan showed neurotoxicity and both pesticides showed developmental effects in the zebrafish assays, although methidathion is not developmentally toxic in vivo. CONCLUSIONS ToxCast's predictions showed concordance on some endpoints and nonconcordance, consisting mainly of false inactives, in several critical endpoints, likely due to a lack of metabolic activation and limitations in assay design. Zebrafish assays were good predictors of developmental toxicity and neurotoxicity for endosulfan.
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Affiliation(s)
- M Silva
- Department of Pesticide Regulation, California Environmental Protection Agency (CalEPA), Sacramento, California
| | - N Pham
- CalEPA's Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, California
| | - C Lewis
- Department of Pesticide Regulation, California Environmental Protection Agency (CalEPA), Sacramento, California
| | - S Iyer
- CalEPA's Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, California
| | - E Kwok
- Department of Pesticide Regulation, California Environmental Protection Agency (CalEPA), Sacramento, California
| | - G Solomon
- Office of the Secretary, CalEPA, Sacramento, California
| | - L Zeise
- CalEPA's Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, California
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26
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Graedel TE, Swackhamer D, Anex R, Carroll WF, Daigger GT, Ferrão P, Frumkin H, Katzen S, Palmisano A, Polasky S, Scarlett L, Stephens R, Zeise L. Sustainability for the nation: resource connections and governance linkages. Environ Sci Technol 2014. [PMID: 24910888 DOI: 10.17226/13471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Affiliation(s)
- T E Graedel
- Center for Industrial Ecology, Yale University , New Haven, Connecticut 06511, United States
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Graedel TE, Swackhamer D, Anex R, Carroll WF, Daigger GT, Ferrão P, Frumkin H, Katzen S, Palmisano A, Polasky S, Scarlett L, Stephens R, Zeise L. Sustainability for the nation: resource connections and governance linkages. Environ Sci Technol 2014; 48:7197-7199. [PMID: 24910888 DOI: 10.1021/es502328v] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- T E Graedel
- Center for Industrial Ecology, Yale University , New Haven, Connecticut 06511, United States
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Zeise L, Bois FY, Chiu WA, Hattis D, Rusyn I, Guyton KZ. Addressing human variability in next-generation human health risk assessments of environmental chemicals. Environ Health Perspect 2013; 121:23-31. [PMID: 23086705 PMCID: PMC3553440 DOI: 10.1289/ehp.1205687] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 10/19/2012] [Indexed: 05/19/2023]
Abstract
BACKGROUND Characterizing variability in the extent and nature of responses to environmental exposures is a critical aspect of human health risk assessment. OBJECTIVE Our goal was to explore how next-generation human health risk assessments may better characterize variability in the context of the conceptual framework for the source-to-outcome continuum. METHODS This review was informed by a National Research Council workshop titled "Biological Factors that Underlie Individual Susceptibility to Environmental Stressors and Their Implications for Decision-Making." We considered current experimental and in silico approaches, and emerging data streams (such as genetically defined human cells lines, genetically diverse rodent models, human omic profiling, and genome-wide association studies) that are providing new types of information and models relevant for assessing interindividual variability for application to human health risk assessments of environmental chemicals. DISCUSSION One challenge for characterizing variability is the wide range of sources of inherent biological variability (e.g., genetic and epigenetic variants) among individuals. A second challenge is that each particular pair of health outcomes and chemical exposures involves combinations of these sources, which may be further compounded by extrinsic factors (e.g., diet, psychosocial stressors, other exogenous chemical exposures). A third challenge is that different decision contexts present distinct needs regarding the identification-and extent of characterization-of interindividual variability in the human population. CONCLUSIONS Despite these inherent challenges, opportunities exist to incorporate evidence from emerging data streams for addressing interindividual variability in a range of decision-making contexts.
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Affiliation(s)
- Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California 94612, USA.
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Balbus JM, Boxall ABA, Fenske RA, McKone TE, Zeise L. Implications of global climate change for the assessment and management of human health risks of chemicals in the natural environment. Environ Toxicol Chem 2013; 32:62-78. [PMID: 23147420 PMCID: PMC3601433 DOI: 10.1002/etc.2046] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 05/08/2012] [Accepted: 09/13/2012] [Indexed: 05/04/2023]
Abstract
Global climate change (GCC) is likely to alter the degree of human exposure to pollutants and the response of human populations to these exposures, meaning that risks of pollutants could change in the future. The present study, therefore, explores how GCC might affect the different steps in the pathway from a chemical source in the environment through to impacts on human health and evaluates the implications for existing risk-assessment and management practices. In certain parts of the world, GCC is predicted to increase the level of exposure of many environmental pollutants due to direct and indirect effects on the use patterns and transport and fate of chemicals. Changes in human behavior will also affect how humans come into contact with contaminated air, water, and food. Dietary changes, psychosocial stress, and coexposure to stressors such as high temperatures are likely to increase the vulnerability of humans to chemicals. These changes are likely to have significant implications for current practices for chemical assessment. Assumptions used in current exposure-assessment models may no longer apply, and existing monitoring methods may not be robust enough to detect adverse episodic changes in exposures. Organizations responsible for the assessment and management of health risks of chemicals therefore need to be more proactive and consider the implications of GCC for their procedures and processes.
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Affiliation(s)
- John M Balbus
- National Institute of Environmental Health Sciences, Bethesda, MD, USA.
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Wise A, Parham F, Axelrad DA, Guyton KZ, Portier C, Zeise L, Zoeller RT, Woodruff TJ. Upstream adverse effects in risk assessment: a model of polychlorinated biphenyls, thyroid hormone disruption and neurological outcomes in humans. Environ Res 2012; 117:90-9. [PMID: 22770859 DOI: 10.1016/j.envres.2012.05.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 05/04/2012] [Accepted: 05/31/2012] [Indexed: 05/22/2023]
Abstract
BACKGROUND Increasing data on early biological changes from chemical exposures requires new interpretation tools to support decision-making. OBJECTIVES To test the possibility of applying a quantitative approach using human data linking chemical exposures and upstream biological perturbations to overt downstream outcomes. METHODS Using polychlorinated biphenyl (PCB) exposures and maternal thyroid hormone (TH) perturbations as a case study, we model three relationships: (1) prenatal PCB exposures and TH changes, using free T(4) (FT(4)); (2) prenatal TH and childhood neurodevelopmental outcomes; and (3) prenatal PCB exposures and childhood neurodevelopmental outcomes (IQ). We surveyed the epidemiological literature; extracted relevant quantitative data; and developed models for each relationship, applying meta-analysis where appropriate. RESULTS For relationship 1, a meta-analysis of 3 studies gives a coefficient of -0.27 pg/mL FT(4) per ln(sum of PCBs) (95% confidence interval [CI] -0.82 to 0.27). For relationship 2, regression coefficients from three studies of maternal FT(4) levels and cognitive scores ranged between 0.99 IQ points/(pg/mL FT(4)) (95% CI -0.31 to 2.2) and 7.6 points/(pg/mL FT(4)) (95% CI 1.2 to 16.3). For relationship 3, a meta-analysis of five studies produces a coefficient of -1.98 IQ points (95% CI -4.46 to 0.50) per unit increase in ln(sum of PCBs). Combining relationships 1 and 2 yields an estimate of -2.0 to -0.27 points of IQ per unit increase in ln(sum of PCBs). CONCLUSIONS Combining analysis of chemical exposures and early biological perturbations (PCBs and FT(4)) with analysis of early biological perturbations and downstream overt effects (FT(4) and IQ) yields estimates within the range of studies of exposures and overt effects (PCBs and IQ). This is an example approach using upstream biological perturbations for effect prediction.
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Affiliation(s)
- Amber Wise
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, United States
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Parham F, Wise A, Axelrad DA, Guyton KZ, Portier C, Zeise L, Zoeller RT, Woodruff TJ. Adverse effects in risk assessment: modeling polychlorinated biphenyls and thyroid hormone disruption outcomes in animals and humans. Environ Res 2012; 116:74-84. [PMID: 22575326 PMCID: PMC4955584 DOI: 10.1016/j.envres.2012.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 03/19/2012] [Accepted: 04/04/2012] [Indexed: 05/02/2023]
Abstract
There is a growing need for quantitative approaches to extrapolate relationships between chemical exposures and early biological perturbations from animals to humans given increasing use of biological assays to evaluate toxicity pathways. We have developed such an approach using polychlorinated biphenyls (PCBs) and thyroid hormone (TH) disruption as a case study. We reviewed and identified experimental animal literature from which we developed a low-dose, linear model of PCB body burdens and decrements in free thyroxine (FT(4)) and total thyroxine (TT(4)), accounting for 33 PCB congeners; extrapolated the dose-response from animals to humans; and compared the animal dose-response to the dose-response of PCB body burdens and TH changes from eleven human epidemiological studies. We estimated a range of potencies for PCB congeners (over 4 orders of magnitude), with the strongest for PCB 126. Our approach to developing toxic equivalency models produced relative potencies similar to the toxicity equivalency factors (TEFs) from the World Health Organization (WHO). We generally found that the dose-response extrapolated from the animal studies tends to under-predict the dose-response estimated from human epidemiological studies. A quantitative approach to evaluating the relationship between chemical exposures and TH perturbations, based on animal data can be used to assess human health consequences of thyroid toxicity and inform decision-making.
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Affiliation(s)
- Fred Parham
- National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Amber Wise
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, USA
| | - Daniel A. Axelrad
- Office of Policy, U.S. Environmental Protection Agency (USEPA), Washington, DC, USA
| | - Kathryn Z. Guyton
- National Center for Environmental Assessment, Office of Research and Development, USEPA, Washington, DC, USA
| | | | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, CA, USA
| | | | - Tracey J. Woodruff
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, USA
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Abstract
Protecting the health of the public-particularly the most vulnerable groups, such as children-requires rethinking current approaches to reducing environmental risks. We review the evolving understanding of the relationship between exposure to chemicals in the environment and disease, as well as the current state of managing those chemicals. We present recommendations to improve current approaches, including changing the burden of proof so that chemicals are not presumed safe in the absence of scientific data. We also propose modernizing approaches to assessing health risks.
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Hakanoglu E, Fiering MB, Croucht EAC, Wilsont R, Zeise L. Prioritization of chemical carcinogenesis testing: the use of production data. ACTA ACUST UNITED AC 2011. [DOI: 10.1080/02630258508970387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Golub MS, Wu KL, Kaufman FL, Li LH, Moran-Messen F, Zeise L, Alexeeff GV, Donald JM. Bisphenol A: developmental toxicity from early prenatal exposure. ACTA ACUST UNITED AC 2011; 89:441-66. [PMID: 21136531 DOI: 10.1002/bdrb.20275] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Bisphenol A (BPA) exposure has been documented in pregnant women, but consequences for development are not yet widely studied in human populations. This review presents research on the consequences for offspring of BPA exposure during pregnancy. Extensive work in laboratory rodents has evaluated survival and growth of the conceptus, interference with embryonic programs of development, morphological sex differentiation, sex differentiation of the brain and behavior, immune responsiveness, and mechanism of action. Sensitive measures include RAR, aryl hydrocarbon receptor, and Hox A10 gene expression, anogenital distance, sex differentiation of affective and exploratory behavior, and immune hyperresponsiveness. Many BPA effects are reported at low doses (10-50 µg/kg d range) by the oral route of administration. At high doses (>500,000 µg/kg d) fetal viability is compromised. Much of the work has centered around the implications of the estrogenic actions of this agent. Some work related to thyroid mechanism of action has also been explored. BPA research has actively integrated current knowledge of developmental biology, concepts of endocrine disruption, and toxicological research to provide a basis for human health risk assessment.
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Affiliation(s)
- Mari S Golub
- Office of Environmental Health Hazard Assessment, Reproductive and Cancer Hazard Assessment Branch, Sacramento, California, USA.
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Ward EM, Schulte PA, Straif K, Hopf NB, Caldwell JC, Carreón T, DeMarini DM, Fowler BA, Goldstein BD, Hemminki K, Hines CJ, Pursiainen KH, Kuempel E, Lewtas J, Lunn RM, Lynge E, McElvenny DM, Muhle H, Nakajima T, Robertson LW, Rothman N, Ruder AM, Schubauer-Berigan MK, Siemiatycki J, Silverman D, Smith MT, Sorahan T, Steenland K, Stevens RG, Vineis P, Zahm SH, Zeise L, Cogliano VJ. Research recommendations for selected IARC-classified agents. Environ Health Perspect 2010; 118:1355-62. [PMID: 20562050 PMCID: PMC2957912 DOI: 10.1289/ehp.0901828] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 06/18/2010] [Indexed: 05/10/2023]
Abstract
OBJECTIVES There are some common occupational agents and exposure circumstances for which evidence of carcinogenicity is substantial but not yet conclusive for humans. Our objectives were to identify research gaps and needs for 20 agents prioritized for review based on evidence of widespread human exposures and potential carcinogenicity in animals or humans. DATA SOURCES For each chemical agent (or category of agents), a systematic review was conducted of new data published since the most recent pertinent International Agency for Research on Cancer (IARC) Monograph meeting on that agent. DATA EXTRACTION Reviewers were charged with identifying data gaps and general and specific approaches to address them, focusing on research that would be important in resolving classification uncertainties. An expert meeting brought reviewers together to discuss each agent and the identified data gaps and approaches. DATA SYNTHESIS Several overarching issues were identified that pertained to multiple agents; these included the importance of recognizing that carcinogenic agents can act through multiple toxicity pathways and mechanisms, including epigenetic mechanisms, oxidative stress, and immuno- and hormonal modulation. CONCLUSIONS Studies in occupational populations provide important opportunities to understand the mechanisms through which exogenous agents cause cancer and intervene to prevent human exposure and/or prevent or detect cancer among those already exposed. Scientific developments are likely to increase the challenges and complexities of carcinogen testing and evaluation in the future, and epidemiologic studies will be particularly critical to inform carcinogen classification and risk assessment processes.
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Affiliation(s)
- Elizabeth M Ward
- Epidemiology and Surveillance Research, American Cancer Society, Atlanta Georgia 30303, USA.
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Abstract
At the request of the U.S. Environmental Protection Agency (EPA), the National Research Council (NRC) recently completed a major report, Science and Decisions: Advancing Risk Assessment, that is intended to strengthen the scientific basis, credibility, and effectiveness of risk assessment practices and subsequent risk management decisions. The report describes the challenges faced by risk assessment and the need to consider improvements in both the technical analyses of risk assessments (i.e., the development and use of scientific information to improve risk characterization) and the utility of risk assessments (i.e., making assessments more relevant and useful for risk management decisions). The report tackles a number of topics relating to improvements in the process, including the design and framing of risk assessments, uncertainty and variability characterization, selection and use of defaults, unification of cancer and noncancer dose-response assessment, cumulative risk assessment, and the need to increase EPA's capacity to address these improvements. This article describes and summarizes the NRC report, with an eye toward its implications for risk assessment practices at EPA.
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Affiliation(s)
- Eileen Abt
- National Research Council, Washington, DC 20001, USA
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Krewski D, Acosta D, Andersen M, Anderson H, Bailar JC, Boekelheide K, Brent R, Charnley G, Cheung VG, Green S, Kelsey KT, Kerkvliet NI, Li AA, McCray L, Meyer O, Patterson RD, Pennie W, Scala RA, Solomon GM, Stephens M, Yager J, Zeise L. Toxicity testing in the 21st century: a vision and a strategy. J Toxicol Environ Health B Crit Rev 2010; 13:51-138. [PMID: 20574894 DOI: 10.1080/10937404.2010.483176.toxicity] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
With the release of the landmark report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U.S. National Academy of Sciences, in 2007, precipitated a major change in the way toxicity testing is conducted. It envisions increased efficiency in toxicity testing and decreased animal usage by transitioning from current expensive and lengthy in vivo testing with qualitative endpoints to in vitro toxicity pathway assays on human cells or cell lines using robotic high-throughput screening with mechanistic quantitative parameters. Risk assessment in the exposed human population would focus on avoiding significant perturbations in these toxicity pathways. Computational systems biology models would be implemented to determine the dose-response models of perturbations of pathway function. Extrapolation of in vitro results to in vivo human blood and tissue concentrations would be based on pharmacokinetic models for the given exposure condition. This practice would enhance human relevance of test results, and would cover several test agents, compared to traditional toxicological testing strategies. As all the tools that are necessary to implement the vision are currently available or in an advanced stage of development, the key prerequisites to achieving this paradigm shift are a commitment to change in the scientific community, which could be facilitated by a broad discussion of the vision, and obtaining necessary resources to enhance current knowledge of pathway perturbations and pathway assays in humans and to implement computational systems biology models. Implementation of these strategies would result in a new toxicity testing paradigm firmly based on human biology.
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Affiliation(s)
- Daniel Krewski
- R Samuel McLaughlin Centre for Population Health Risk Assessment, Institute of Population Health, University of Ottawa, Ottawa, Ontario, Canada.
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Krewski D, Acosta D, Andersen M, Anderson H, Bailar JC, Boekelheide K, Brent R, Charnley G, Cheung VG, Green S, Kelsey KT, Kerkvliet NI, Li AA, McCray L, Meyer O, Patterson RD, Pennie W, Scala RA, Solomon GM, Stephens M, Yager J, Zeise L. Toxicity testing in the 21st century: a vision and a strategy. J Toxicol Environ Health B Crit Rev 2010; 13:51-138. [PMID: 20574894 PMCID: PMC4410863 DOI: 10.1080/10937404.2010.483176] [Citation(s) in RCA: 473] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
With the release of the landmark report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U.S. National Academy of Sciences, in 2007, precipitated a major change in the way toxicity testing is conducted. It envisions increased efficiency in toxicity testing and decreased animal usage by transitioning from current expensive and lengthy in vivo testing with qualitative endpoints to in vitro toxicity pathway assays on human cells or cell lines using robotic high-throughput screening with mechanistic quantitative parameters. Risk assessment in the exposed human population would focus on avoiding significant perturbations in these toxicity pathways. Computational systems biology models would be implemented to determine the dose-response models of perturbations of pathway function. Extrapolation of in vitro results to in vivo human blood and tissue concentrations would be based on pharmacokinetic models for the given exposure condition. This practice would enhance human relevance of test results, and would cover several test agents, compared to traditional toxicological testing strategies. As all the tools that are necessary to implement the vision are currently available or in an advanced stage of development, the key prerequisites to achieving this paradigm shift are a commitment to change in the scientific community, which could be facilitated by a broad discussion of the vision, and obtaining necessary resources to enhance current knowledge of pathway perturbations and pathway assays in humans and to implement computational systems biology models. Implementation of these strategies would result in a new toxicity testing paradigm firmly based on human biology.
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Affiliation(s)
- Daniel Krewski
- R Samuel McLaughlin Centre for Population Health Risk Assessment, Institute of Population Health, University of Ottawa, Ottawa, Ontario, Canada.
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Abstract
At the request of the Environmental Protection Agency, the National Research Council (NRC) recently completed a major report entitled Toxicity Testing in the 21st Century: A Vision and a Strategy. The terms of reference for this report were to develop a long-range vision and strategic plan to advance the practices of toxicity testing and human health assessment of environmental agents. The report describes how current and anticipated scientific advances can be expected to transform toxicity testing to permit broader coverage of the universe of potentially toxic chemicals to which humans may be exposed, using more timely and more cost-effective methods for toxicity testing. The report envisages greatly expanded use of high- and medium-throughput in vitro screening assays, computational toxicology, and systems biology, along with other emerging high-content testing methodologies, such as functional genomics and transcriptomics. When fully implemented, the vision will transform the ways toxicity testing and chemical risk assessment are conducted, moving away from measuring apical health endpoints in experimental animals toward identification of significant perturbations of toxicity pathways using in vitro tests in human cells and cell lines. Population-based studies incorporating relevant biomarkers will also be useful in identifying pathway perturbations directly in humans and in interpreting the results of in vitro tests in the context of human health risk assessment. The present article summarizes and extends the NRC report and examines its implications for risk assessment practice.
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White RH, Cote I, Zeise L, Fox M, Dominici F, Burke TA, White PD, Hattis DB, Samet JM. State-of-the-science workshop report: issues and approaches in low-dose-response extrapolation for environmental health risk assessment. Environ Health Perspect 2009; 117:283-7. [PMID: 19270800 PMCID: PMC2649232 DOI: 10.1289/ehp.11502] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Accepted: 09/19/2008] [Indexed: 05/02/2023]
Abstract
Low-dose extrapolation model selection for evaluating the health effects of environmental pollutants is a key component of the risk assessment process. At a workshop held in Baltimore, Maryland, on 23-24 April 2007, sponsored by U.S. Environmental Protection Agency and Johns Hopkins Risk Sciences and Public Policy Institute, a multidisciplinary group of experts reviewed the state of the science regarding low-dose extrapolation modeling and its application in environmental health risk assessments. Participants identified discussion topics based on a literature review, which included examples for which human responses to ambient exposures have been extensively characterized for cancer and/or noncancer outcomes. Topics included the need for formalized approaches and criteria to assess the evidence for mode of action (MOA), the use of human versus animal data, the use of MOA information in biologically based models, and the implications of interindividual variability, background disease processes, and background exposures in threshold versus nonthreshold model choice. Participants recommended approaches that differ from current practice for extrapolating high-dose animal data to low-dose human exposures, including categorical approaches for integrating information on MOA, statistical approaches such as model averaging, and inference-based models that explicitly consider uncertainty and interindividual variability.
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Affiliation(s)
- Ronald H White
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, USA.
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Woodruff TJ, Zeise L, Axelrad DA, Guyton KZ, Janssen S, Miller M, Miller GG, Schwartz JM, Alexeeff G, Anderson H, Birnbaum L, Bois F, Cogliano VJ, Crofton K, Euling SY, Foster PMD, Germolec DR, Gray E, Hattis DB, Kyle AD, Luebke RW, Luster MI, Portier C, Rice DC, Solomon G, Vandenberg J, Zoeller RT. Meeting report: moving upstream-evaluating adverse upstream end points for improved risk assessment and decision-making. Environ Health Perspect 2008; 116:1568-75. [PMID: 19057713 PMCID: PMC2592280 DOI: 10.1289/ehp.11516] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Accepted: 07/09/2008] [Indexed: 05/02/2023]
Abstract
BACKGROUND Assessing adverse effects from environmental chemical exposure is integral to public health policies. Toxicology assays identifying early biological changes from chemical exposure are increasing our ability to evaluate links between early biological disturbances and subsequent overt downstream effects. A workshop was held to consider how the resulting data inform consideration of an "adverse effect" in the context of hazard identification and risk assessment. OBJECTIVES Our objective here is to review what is known about the relationships between chemical exposure, early biological effects (upstream events), and later overt effects (downstream events) through three case studies (thyroid hormone disruption, antiandrogen effects, immune system disruption) and to consider how to evaluate hazard and risk when early biological effect data are available. DISCUSSION Each case study presents data on the toxicity pathways linking early biological perturbations with downstream overt effects. Case studies also emphasize several factors that can influence risk of overt disease as a result from early biological perturbations, including background chemical exposures, underlying individual biological processes, and disease susceptibility. Certain effects resulting from exposure during periods of sensitivity may be irreversible. A chemical can act through multiple modes of action, resulting in similar or different overt effects. CONCLUSIONS For certain classes of early perturbations, sufficient information on the disease process is known, so hazard and quantitative risk assessment can proceed using information on upstream biological perturbations. Upstream data will support improved approaches for considering developmental stage, background exposures, disease status, and other factors important to assessing hazard and risk for the whole population.
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Affiliation(s)
- Tracey J Woodruff
- Department of Obstetrics and Gynecology, University of California, San Francisco, California, USA.
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Affiliation(s)
- L Zeise
- Facility for Advanced Instrumentation, University of California, Davis 95616
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Beaumont J, Sedman R, Reynolds S, Sherman C, Li LH, Howd R, Sandy M, Zeise L, Alexeeff G. Analysis of Cancer Mortality Data from Five Villages in China with Hexavalent Chromium-Contaminated Drinking Water. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s115-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Arcus-Arth A, Krowech G, Zeise L. Breast milk and lipid intake distributions for assessing cumulative exposure and risk. J Expo Anal Environ Epidemiol 2005; 15:357-65. [PMID: 15562290 DOI: 10.1038/sj.jea.7500412] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Breast milk consumption is the primary route of infant exposure to certain lipophilic toxicants that have accumulated over decades in maternal adipose tissue, as well as to less persistent toxicants from maternal exposure during lactation. Such infant exposures occur at a time of rapid growth and development when susceptibility to certain toxicants can be greatest. Breast milk and lipid intake rates are presented for the 0-6 and 0-12 month age periods for infants fed according to the American Academy of Pediatrics' current recommendations (exclusive breast-feeding for 0-6 months and continued breast-feeding to 12 months). Intake rates are normalized to infant bodyweight to account for the covariance of consumption and bodyweight. Frequency distributions describe the population variability in intake. For age 0-12 months, daily average milk intake is 100.7 +/- 22.7 g/kg day (mean +/- SD), with a 95th percentile of 153.5 g/kg day. Breast milk intake distributions are also developed for infants exclusively breast-fed (no significant calories from non-breast milk sources) over their first year, and for the entire (nursing and non-nursing) infant population. For short-term exposures, intake can be derived from the regression equation presented here. Lipid intake estimated assuming a 4% lipid content (current risk assessment practice) is compared and found comparable to that derived from measured lipid content. The national trend of increased breast-feeding found in surveys further supports including the breast milk pathway in risk assessment.
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Affiliation(s)
- Amy Arcus-Arth
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, USA.
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Affiliation(s)
- L Zeise
- California Environmental Protection Agency, Office of Environmental Health Hazard Assessment, Oakland, USA
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Krewski D, Cardis E, Zeise L, Feron VJ. Empirical approaches to risk estimation and prediction. IARC Sci Publ 1999:131-78. [PMID: 10505296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- D Krewski
- University of Ottawa, Department of Medicine, Ontario, Canada
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Cardis E, Zeise L, Schwarz M, Moolgavkar S. Review of specific examples of QEP. IARC Sci Publ 1999:239-304. [PMID: 10505298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- E Cardis
- Unit of Radiation and Cancer, International Agency for Research on Cancer, Lyon, France
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Zeise L, Cardis E, Hemminki K, Schwarz M. Quantitative estimation and prediction of cancer risk: review of existing activities. IARC Sci Publ 1999:11-59. [PMID: 10505292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- L Zeise
- Reproductive and Cancer Hazard Assessment Section, Office of Environmental Health Hazard Assessment, Oakland, CA 94612, USA
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Moolgavkar S, Woodward A, Krewski D, Cardis E, Zeise L. Future perspectives, unresolved issues and research needs. IARC Sci Publ 1999:305-22. [PMID: 10505299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- S Moolgavkar
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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