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Nicolas CI, Linakis MW, Minto MS, Mansouri K, Clewell RA, Yoon M, Wambaugh JF, Patlewicz G, McMullen PD, Andersen ME, Clewell III HJ. Estimating provisional margins of exposure for data-poor chemicals using high-throughput computational methods. Front Pharmacol 2022; 13:980747. [PMID: 36278238 PMCID: PMC9586287 DOI: 10.3389/fphar.2022.980747] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Current computational technologies hold promise for prioritizing the testing of the thousands of chemicals in commerce. Here, a case study is presented demonstrating comparative risk-prioritization approaches based on the ratio of surrogate hazard and exposure data, called margins of exposure (MoEs). Exposures were estimated using a U.S. EPA’s ExpoCast predictive model (SEEM3) results and estimates of bioactivity were predicted using: 1) Oral equivalent doses (OEDs) derived from U.S. EPA’s ToxCast high-throughput screening program, together with in vitro to in vivo extrapolation and 2) thresholds of toxicological concern (TTCs) determined using a structure-based decision-tree using the Toxtree open source software. To ground-truth these computational approaches, we compared the MoEs based on predicted noncancer TTC and OED values to those derived using the traditional method of deriving points of departure from no-observed adverse effect levels (NOAELs) from in vivo oral exposures in rodents. TTC-based MoEs were lower than NOAEL-based MoEs for 520 out of 522 (99.6%) compounds in this smaller overlapping dataset, but were relatively well correlated with the same (r2 = 0.59). TTC-based MoEs were also lower than OED-based MoEs for 590 (83.2%) of the 709 evaluated chemicals, indicating that TTCs may serve as a conservative surrogate in the absence of chemical-specific experimental data. The TTC-based MoE prioritization process was then applied to over 45,000 curated environmental chemical structures as a proof-of-concept for high-throughput prioritization using TTC-based MoEs. This study demonstrates the utility of exploiting existing computational methods at the pre-assessment phase of a tiered risk-based approach to quickly, and conservatively, prioritize thousands of untested chemicals for further study.
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Affiliation(s)
- Chantel I. Nicolas
- Office of Chemical Safety and Pollution Prevention, US EPA, Washington, DC, United States
| | | | | | - Kamel Mansouri
- National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods, Research Triangle Park, NC, United States
| | | | | | - John F. Wambaugh
- Center for Computational Toxicology and Exposure Office of Research and Development, US EPA, Research Triangle Park, NC, United States
| | - Grace Patlewicz
- Center for Computational Toxicology and Exposure Office of Research and Development, US EPA, Research Triangle Park, NC, United States
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Duan Y, Ramilan T, Luo J, French N, Guan N. Risk assessment approaches for evaluating cumulative exposures to multiple pesticide residues in agro-products using seasonal vegetable monitoring data from Hainan, China: a case study. ENVIRONMENTAL MONITORING AND ASSESSMENT 2021; 193:578. [PMID: 34398280 DOI: 10.1007/s10661-021-09328-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 07/17/2021] [Indexed: 06/13/2023]
Abstract
Risks from combined exposure to multiple chemicals in food have prompted a growing concern for their effect on human health. Risk management of chemical mixtures should be based on developing and harmonizing methodologies to scientifically evaluate their cumulative adverse effects. In this study, a simplified tiered approach of cumulative exposure assessment is described along with a case study of vegetables in China's Hainan province during 2012-2014. This case study could be a reference for the Chinese National Risk Assessment Programs for vegetable and fruit products. In the proposed assessment approach, Tier 1 acts as a screening tier to categorize and evaluate chemicals under a conservative scenario, and it prioritizes the pesticides of most concern. Tier 2 refines the grouping of substances from Tier 1 and normalizes the toxic potency of the chemicals to sum the exposure of chemical mixtures in a given assessment group. Tier 3 applies the refined exposure model and the input parameter distribution to create probabilistic models using Monte Carlo simulation. This approach will be helpful in the cumulative exposure assessment where data on pesticide residues are sufficient, but the individual dietary consumption is inadequate.
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Affiliation(s)
- Yun Duan
- Analysis and Test Center, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
- Laboratory of Quality and Safety Risk Assessment for Tropical Products of Ministry of Agriculture and Rural Affairs, Haikou, China
- Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Haikou, China
- Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
- New Zealand Food Safety Science & Research Center, Palmerston North, New Zealand
| | - Thiagarajah Ramilan
- New Zealand Food Safety Science & Research Center, Palmerston North, New Zealand.
- School of Agriculture and Environment, Massey University, Palmerston North, New Zealand.
| | - Jinhui Luo
- Analysis and Test Center, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
- Laboratory of Quality and Safety Risk Assessment for Tropical Products of Ministry of Agriculture and Rural Affairs, Haikou, China
- Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Haikou, China
| | - Nigel French
- Hopkirk Research Institute, Massey University, Palmerston North, New Zealand.
- New Zealand Food Safety Science & Research Center, Palmerston North, New Zealand.
| | - Ni Guan
- National Engineering Research Center for Non-Food Bio-Refinery, Guangxi Academy of Science, Nanning, China
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3
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Patel A, Joshi K, Rose J, Laufersweiler M, Felter SP, Api AM. Bolstering the existing database supporting the non-cancer Threshold of Toxicological Concern values with toxicity data on fragrance-related materials. Regul Toxicol Pharmacol 2020; 116:104718. [DOI: 10.1016/j.yrtph.2020.104718] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 10/24/2022]
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4
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The TTC Data Mart: An interactive browser for threshold of toxicological concern calculations. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.comtox.2020.100128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Nelms MD, Pradeep P, Patlewicz G. Evaluating potential refinements to existing Threshold of Toxicological Concern (TTC) values for environmentally-relevant compounds. Regul Toxicol Pharmacol 2019; 109:104505. [PMID: 31639428 DOI: 10.1016/j.yrtph.2019.104505] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/12/2019] [Accepted: 10/15/2019] [Indexed: 11/29/2022]
Abstract
The Toxic Substances Control Act (TSCA) mandates the US EPA perform risk-based prioritisation of chemicals in commerce and then, for high-priority substances, develop risk evaluations that integrate toxicity data with exposure information. One approach being considered for data poor chemicals is the Threshold of Toxicological Concern (TTC). Here, TTC values derived using oral (sub)chronic No Observable (Adverse) Effect Level (NO(A)EL) data from the EPA's Toxicity Values database (ToxValDB) were compared with published TTC values from Munro et al. (1996). A total of 4554 chemicals with structures present in ToxValDB were assigned into their respective TTC categories using the Toxtree software tool, of which toxicity data was available for 1304 substances. The TTC values derived from ToxValDB were similar, but not identical to the Munro TTC values: Cramer I ((ToxValDB) 37.3 c. f. (Munro) 30 μg/kg-day), Cramer II (34.6 c. f. 9.1 μg/kg-day) and Cramer III (3.9 c. f. 1.5 μg/kg-day). Cramer III 5th percentile values were found to be statistically different. Chemical features of the two Cramer III datasets were evaluated to account for the differences. TTC values derived from this expanded dataset substantiated the original TTC values, reaffirming the utility of TTC as a promising tool in a risk-based prioritisation approach.
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Affiliation(s)
- Mark D Nelms
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, 37830, USA; Center for Computational Toxicology & Exposure (CCTE), U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC, 27709, USA
| | - Prachi Pradeep
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, 37830, USA; Center for Computational Toxicology & Exposure (CCTE), U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC, 27709, USA
| | - Grace Patlewicz
- Center for Computational Toxicology & Exposure (CCTE), U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC, 27709, USA.
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Reilly L, Serafimova R, Partosch F, Gundert-Remy U, Cortiñas Abrahantes J, Dorne JLM, Kass GE. Testing the thresholds of toxicological concern values using a new database for food-related substances. Toxicol Lett 2019; 314:117-123. [DOI: 10.1016/j.toxlet.2019.07.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 07/06/2019] [Accepted: 07/15/2019] [Indexed: 11/24/2022]
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More SJ, Bampidis V, Benford D, Bragard C, Halldorsson TI, Hernández-Jerez AF, Hougaard Bennekou S, Koutsoumanis KP, Machera K, Naegeli H, Nielsen SS, Schlatter JR, Schrenk D, Silano V, Turck D, Younes M, Gundert-Remy U, Kass GEN, Kleiner J, Rossi AM, Serafimova R, Reilly L, Wallace HM. Guidance on the use of the Threshold of Toxicological Concern approach in food safety assessment. EFSA J 2019; 17:e05708. [PMID: 32626331 PMCID: PMC7009090 DOI: 10.2903/j.efsa.2019.5708] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The Scientific Committee confirms that the Threshold of Toxicological Concern (TTC) is a pragmatic screening and prioritisation tool for use in food safety assessment. This Guidance provides clear step-by-step instructions for use of the TTC approach. The inclusion and exclusion criteria are defined and the use of the TTC decision tree is explained. The approach can be used when the chemical structure of the substance is known, there are limited chemical-specific toxicity data and the exposure can be estimated. The TTC approach should not be used for substances for which EU food/feed legislation requires the submission of toxicity data or when sufficient data are available for a risk assessment or if the substance under consideration falls into one of the exclusion categories. For substances that have the potential to be DNA-reactive mutagens and/or carcinogens based on the weight of evidence, the relevant TTC value is 0.0025 μg/kg body weight (bw) per day. For organophosphates or carbamates, the relevant TTC value is 0.3 μg/kg bw per day. All other substances are grouped according to the Cramer classification. The TTC values for Cramer Classes I, II and III are 30 μg/kg bw per day, 9 μg/kg bw per day and 1.5 μg/kg bw per day, respectively. For substances with exposures below the TTC values, the probability that they would cause adverse health effects is low. If the estimated exposure to a substance is higher than the relevant TTC value, a non-TTC approach is required to reach a conclusion on potential adverse health effects.
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Blackburn K, Ellison C, Stuard S, Wu S. Dosimetry considerations for in vivo and in vitro test data and a novel surrogate iTTC approach for read-across based on metabolites. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.comtox.2018.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Houben G, Blom M, Alvito P, Assunção R, Crevel R, Fæste CK, Le TM, Madsen CB, Remington B, Stroheker T, Vassilopoulou E, Verhoeckx K, Žiarovská J, Constable A. Defining the targets for the assessment of IgE-mediated allergenicity of new or modified food proteins. Food Chem Toxicol 2019; 127:61-69. [PMID: 30826409 DOI: 10.1016/j.fct.2019.02.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/20/2019] [Accepted: 02/25/2019] [Indexed: 12/20/2022]
Abstract
Many food innovations rely on the introduction and use of new or modified proteins. New or modified food proteins may lead to major health risks due to their inherent potential to cause food allergy. Currently, the pre-market allergenicity assessment for new or modified food proteins and protein sources relies on methods for identifying allergenic hazards based on characteristics of known allergens. However, there is no general consensus on the allergenicity parameters to use and the criteria that should apply for the evaluation and decisions to be made. In this paper, we propose that the strategy for allergenicity risk assessment of new or modified food proteins and the methodologies applied should be governed by the risk management questions to be answered, reflected in the information needed by risk managers to enable their informed decision making. We generated an inventory of health outcome-related assessment parameters and criteria potentially important for risk management decision-making and we discuss the implications of selecting different optional criteria (e.g. cut-off values) for what could be accepted as safe with regards to the health outcomes in the (at risk) population. The impact of these various options on both method development and risk management practices was investigated.
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Affiliation(s)
| | | | - Paula Alvito
- National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
| | - Ricardo Assunção
- National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
| | | | | | - Thuy-My Le
- University Medical Center Utrecht, Utrecht, the Netherlands
| | | | | | | | | | | | - Jana Žiarovská
- Slovak University of Agriculture, Nitra, Slovak Republic
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10
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Risk assessment for migration of styrene oligomers into food from polystyrene food containers. Food Chem Toxicol 2019; 124:151-167. [DOI: 10.1016/j.fct.2018.11.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 11/05/2018] [Accepted: 11/07/2018] [Indexed: 01/20/2023]
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11
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Harvey J, Fleetwood A, Ogilvie R, Teasdale A, Wilcox P, Spanhaak S. Management of organic impurities in small molecule medicinal products: Deriving safe limits for use in early development. Regul Toxicol Pharmacol 2016; 84:116-123. [PMID: 28038978 DOI: 10.1016/j.yrtph.2016.12.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 11/17/2022]
Abstract
Management of organic non-mutagenic impurities (NMIs) in medicinal products is regulated by the ICH Q3A, B and C guidelines that are applicable at late stages of clinical development (Phase III onwards) and as a consequence there is no guidance for the assessment and control of NMIs in early clinical trials. An analysis of several key in vivo toxicology databases supports the ICH Q3A defined concept that a lifetime dose to 1 mg/day of a NMI would not represent a safety concern to patients. In conjunction with routine (Q)SAR approaches, this 1 mg/day value could be used as a universal qualification threshold for a NMI during any stage of clinical development. This analysis also proposes that modification of this 1 mg/day dose using an established methodology (i.e. Modified Haber's Law) could support 5 mg/day or 0.7% (whichever is lower) as an acceptable limit for a NMI in a drug substance or product in early clinical studies (<6 months). Given the controlled nature of clinical development and the knowledge that most toxicities are dose and duration dependent, these proposed NMI limits provide assurance of patient safety throughout clinical development, without the requirement to commission dedicated in vivo toxicology impurity qualification studies.
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Affiliation(s)
- James Harvey
- GlaxoSmithKline R&D, Park Road, Ware, Hertfordshire, SG12 0DP, United Kingdom.
| | | | - Ron Ogilvie
- Pfizer, Ramsgate Road Sandwich, Kent, CT13 9N, United Kingdom
| | - Andrew Teasdale
- AstraZeneca, Silk Road Business Park, Macclesfield, Cheshire, SK10 2NX, United Kingdom
| | - Phil Wilcox
- GlaxoSmithKline R&D, Park Road, Ware, Hertfordshire, SG12 0DP, United Kingdom
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12
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Bao Loan HN, Jacxsens L, Kurshed AAM, De Meulenaer B. 3-Chlorotyrosine formation in ready-to-eat vegetables due to hypochlorite treatment and its dietary exposure and risk assessment. Food Res Int 2016; 90:186-193. [DOI: 10.1016/j.foodres.2016.10.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Revised: 10/25/2016] [Accepted: 10/29/2016] [Indexed: 11/16/2022]
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13
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Relevance of bioaccumulating substances in the TTC concept. Regul Toxicol Pharmacol 2016; 77:42-8. [DOI: 10.1016/j.yrtph.2016.02.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/10/2016] [Accepted: 02/22/2016] [Indexed: 11/24/2022]
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Hanlon P, Brorby GP, Krishan M. A Risk-Based Strategy for Evaluating Mitigation Options for Process-Formed Compounds in Food: Workshop Proceedings. Int J Toxicol 2016; 35:358-70. [PMID: 27102178 PMCID: PMC4871173 DOI: 10.1177/1091581816640262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Processing (eg, cooking, grinding, drying) has changed the composition of food throughout the course of human history; however, awareness of process-formed compounds, and the potential need to mitigate exposure to those compounds, is a relatively recent phenomenon. In May 2015, the North American Branch of the International Life Sciences Institute (ILSI North America) Technical Committee on Food and Chemical Safety held a workshop on the risk-based process for mitigation of process-formed compounds. This workshop aimed to gain alignment from academia, government, and industry on a risk-based process for proactively assessing the need for and benefit of mitigation of process-formed compounds, including criteria to objectively assess the impact of mitigation as well as research needed to support this process. Workshop participants provided real-time feedback on a draft framework in the form of a decision tree developed by the ILSI North America Technical Committee on Food and Chemical Safety to a panel of experts, and they discussed the importance of communicating the value of such a process to the larger scientific community and, ultimately, the public. The outcome of the workshop was a decision tree that can be used by the scientific community and could form the basis of a global approach to assessing the risks associated with mitigation of process-formed compounds.
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Affiliation(s)
| | | | - Mansi Krishan
- North American Branch of the International Life Sciences Institute, Washington, DC, USA
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15
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Buist HE, Krul L, Leeman WR. A TTC threshold for acute oral exposure to non-genotoxic substances. Regul Toxicol Pharmacol 2016; 76:217-20. [PMID: 26853733 DOI: 10.1016/j.yrtph.2016.01.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/29/2016] [Indexed: 11/16/2022]
Abstract
To derive an acute TTC threshold, the correlation between Allowable Daily Intakes (ADIs, chronic values) and Acute Reference Doses (ARfDs) of pesticides evaluated in the EU was investigated and their distributions were compared. The correlation between ARfDs and ADIs was significant (p = 0.01), but weak (r(2) = 0.051). Consequently, using this approach to derive acute TTC values does not seem valid. Therefore, the distributions of ARfDs and ADIs were compared directly, in order to extrapolate from chronic to acute TTC values. This comparison made for the combined Cramer structural class II and III pesticides showed a ratio ARfD/ADI of approximately 3 at the fifth percentile of the distributions. Based on these results, it is justified to propose a TTC for acute effects for Cramer III substances by multiplying the Cramer class III TTC threshold of 90 μg/person/day with a factor 3. This leads to an acute TTC threshold based on the Munro dataset for Cramer class III substances of 270 μg/person/day.
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16
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Leeman W, Krul L. Non-intentionally added substances in food contact materials: how to ensure consumer safety. Curr Opin Food Sci 2015. [DOI: 10.1016/j.cofs.2015.11.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Thiel A, Etheve S, Fabian E, Leeman W, Plautz J. Using in vitro/in silico data for consumer safety assessment of feed flavoring additives – A feasibility study using piperine. Regul Toxicol Pharmacol 2015; 73:73-84. [DOI: 10.1016/j.yrtph.2015.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 12/01/2022]
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18
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Zarn JA, Hänggi E, Engeli BE. Impact of study design and database parameters on NOAEL distributions used for toxicological concern (TTC) values. Regul Toxicol Pharmacol 2015; 72:491-500. [DOI: 10.1016/j.yrtph.2015.05.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/17/2015] [Accepted: 05/13/2015] [Indexed: 10/23/2022]
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Koster S, Leeman W, Verheij E, Dutman E, van Stee L, Nielsen LM, Ronsmans S, Noteborn H, Krul L. A novel safety assessment strategy applied to non-selective extracts. Food Chem Toxicol 2015; 80:163-181. [DOI: 10.1016/j.fct.2015.03.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 01/22/2015] [Accepted: 03/07/2015] [Indexed: 11/16/2022]
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20
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Stanard B, Dolan DG, Hanneman W, Legare M, Bercu JP. Threshold of toxicological concern (TTC) for developmental and reproductive toxicity of anticancer compounds. Regul Toxicol Pharmacol 2015; 72:602-9. [PMID: 26025210 DOI: 10.1016/j.yrtph.2015.05.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 05/21/2015] [Accepted: 05/22/2015] [Indexed: 11/18/2022]
Abstract
Pharmaceutical companies develop specialized therapies to treat late stage cancer. In order to accelerate life-saving treatments and reduce animal testing, compounds to treat life-threatening malignancies are allowed modified requirements for preclinical toxicology testing. Limited data packages in early drug development can present product quality challenges at multi-product manufacturing facilities. The present analysis established an endpoint-specific threshold of toxicological concern (TTC) for developmental and reproductive toxicity (DART) for anticancer compounds. A comprehensive database was created consisting of over 300 no-observed adverse effect levels (NOAELs) for DART of 108 anticancer compounds. The 5th percentile NOAEL for developmental and reproductive toxicity was 0.005 mg/kg/day (300 μg/day), resulting in a human exposure threshold of 3 μg/day assuming standard uncertainty factors and a 60 kg human bodyweight. The analysis shows this threshold is protective for developmental and reproductive toxicity of highly potent groups of anticancer compounds. There were similar TTC values calculated for direct-acting and indirect-acting anticancer compounds.
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Affiliation(s)
- Brad Stanard
- MedImmune, One MedImmune Way, Gaithersburg, MD 20878, USA; Colorado State University, Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Ft. Collins, CO 80523, USA.
| | - David G Dolan
- Amgen, Inc., One Amgen Center Drive, MS 28-1A, Thousand Oaks, CA 91360, USA
| | - William Hanneman
- Colorado State University, Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Ft. Collins, CO 80523, USA
| | - Marie Legare
- Colorado State University, Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Ft. Collins, CO 80523, USA
| | - Joel P Bercu
- Amgen, Inc., One Amgen Center Drive, MS 28-1A, Thousand Oaks, CA 91360, USA
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Etchepare R, van der Hoek JP. Health risk assessment of organic micropollutants in greywater for potable reuse. WATER RESEARCH 2015; 72:186-198. [PMID: 25472689 DOI: 10.1016/j.watres.2014.10.048] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 08/11/2014] [Accepted: 10/21/2014] [Indexed: 06/04/2023]
Abstract
In light of the increasing interest in development of sustainable potable reuse systems, additional research is needed to elucidate the risks of producing drinking water from new raw water sources. This article investigates the presence and potential health risks of organic micropollutants in greywater, a potential new source for potable water production introduced in this work. An extensive literature survey reveals that almost 280 organic micropollutants have been detected in greywater. A three-tiered approach is applied for the preliminary health risk assessment of these chemicals. Benchmark values are derived from established drinking water standards for compounds grouped in Tier 1, from literature toxicological data for compounds in Tier 2, and from a Threshold of Toxicological Concern approach for compounds in Tier 3. A risk quotient is estimated by comparing the maximum concentration levels reported in greywater to the benchmark values. The results show that for the majority of compounds, risk quotient values were below 0.2, which suggests they would not pose appreciable concern to human health over a lifetime exposure to potable water. Fourteen compounds were identified with risk quotients above 0.2 which may warrant further investigation if greywater is used as a source for potable reuse. The present findings are helpful in prioritizing upcoming greywater quality monitoring and defining the goals of multiple barriers treatment in future water reclamation plants for potable water production.
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Affiliation(s)
- Ramiro Etchepare
- Laboratório de Tecnologia Mineral e Ambiental, Departamento de Engenharia de Minas, PPGE3M, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS, Brazil; CAPES Foundation, Ministry of Education of Brazil, Brasília DF 70.040-020, Brazil.
| | - Jan Peter van der Hoek
- Delft University of Technology, Department Water Management, Stevinweg 1, 2628 CN Delft, The Netherlands; Waternet, Strategic Centre, Korte Ouderkerkerdijk 7, 1096 AC Amsterdam, The Netherlands.
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Feigenbaum A, Pinalli R, Giannetto M, Barlow S. Reliability of the TTC approach: Learning from inclusion of pesticide active substances in the supporting database. Food Chem Toxicol 2015; 75:24-38. [DOI: 10.1016/j.fct.2014.10.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 08/05/2014] [Accepted: 10/15/2014] [Indexed: 11/15/2022]
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