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Bauer JA, Romano ME, Jackson BP, Bellinger D, Korrick S, Karagas MR. Associations of Perinatal Metal and Metalloid Exposures with Early Child Behavioral Development Over Time in the New Hampshire Birth Cohort Study. EXPOSURE AND HEALTH 2024; 16:135-148. [PMID: 38694196 PMCID: PMC11060719 DOI: 10.1007/s12403-023-00543-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 01/13/2023] [Accepted: 03/01/2023] [Indexed: 05/04/2024]
Abstract
Research on the neurodevelopmental effects of metal(loid)s has focused mainly on outcomes assessed at one time point, even though brain development progresses over time. We investigated biomarkers of perinatal exposure to metals and changes in child behavior over time. We followed 268 participants from the prospective New Hampshire Birth Cohort Study between birth and age 5 years. We measured arsenic (As), copper (Cu), manganese (Mn), lead (Pb), selenium (Se), and zinc (Zn) in toenails from 6-week-old infants. The Behavioral Symptoms Index (BSI), externalizing, and internalizing symptoms were assessed using the Behavior Assessment System for Children, 2nd edition (BASC-2) at ages 3 and 5 years. Multivariable linear regression was used to estimate associations of metals with behavior change, calculated as the difference in symptom raw scores between 3 and 5 years, in addition to the associations for symptom scores at 3 and 5 years separately. Sex-specific associations were also explored using stratified models and a sex-metal interaction term. Adjusted associations of metals and change in behavior varied by exposure and outcome. Each 1 μg/g increase in ln toenail Cu was associated with improved behavior between 3 and 5 years [BSI: β = - 3.88 (95%CI: - 7.12, - 0.64); Externalizing problems: β = - 2.20 (95%CI: - 4.07, - 0.33)]. Increasing Zn was associated with increased externalizing behavior over time (β = 3.42 (95%CI: 0.60, 6.25). Sex-stratified analyses suggested more pronounced associations among boys compared to girls. Perinatal exposure to metals may alter behavioral development between ages 3 and 5 years. Findings support the need for more research on associations between metals and neurodevelopment over longer time periods.
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Affiliation(s)
- Julia A. Bauer
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, 1 Medical Center Dr., Lebanon, Hanover, NH 03756, USA
| | - Megan E. Romano
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, 1 Medical Center Dr., Lebanon, Hanover, NH 03756, USA
| | - Brian P. Jackson
- Department of Earth Sciences, Dartmouth College, Hanover, NH, USA
| | - David Bellinger
- Departments of Neurology and Psychiatry, Boston Children’s Hospital, Boston, MA, USA
- Departments of Neurology and Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Susan Korrick
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Channing Division of Network Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Margaret R. Karagas
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, 1 Medical Center Dr., Lebanon, Hanover, NH 03756, USA
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Krzeczkowski JE, Hall M, Saint-Amour D, Oulhote Y, McGuckin T, Goodman CV, Green R, Muckle G, Lanphear B, Till C. Prenatal fluoride exposure, offspring visual acuity and autonomic nervous system function in 6-month-old infants. ENVIRONMENT INTERNATIONAL 2024; 183:108336. [PMID: 38064923 PMCID: PMC10981044 DOI: 10.1016/j.envint.2023.108336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 11/10/2023] [Accepted: 11/17/2023] [Indexed: 01/25/2024]
Abstract
BACKGROUND Prenatal fluoride exposure can have adverse effects on children's development; however, associations with visual and cardiac autonomic nervous system functioning are unknown. We examined associations between prenatal fluoride exposure and visual acuity and heart rate variability (HRV) in 6-month-old infants. METHODS We used data from Canadian mother-infant pairs participating in the Maternal-Infant Research on Environmental Chemicals (MIREC) cohort. We estimated prenatal fluoride exposure using: i) fluoride concentration in drinking water (mg/L), ii) maternal urinary fluoride adjusted for specific gravity (MUFSG; mg/L) and averaged across pregnancy, and iii) maternal fluoride intake (µg/kg/day) from consumption of water, tea, and coffee, adjusted for maternal body weight (kg). We used multivariable linear regression to examine associations between each measure of fluoride exposure and Teller Acuity Card visual acuity scores (n = 435) and assessed HRV (n = 400) using two measures: root mean square of successive differences (RMSSD) and the standard deviation of N-N intervals (SDNN) measured at 6-months of age. RESULTS Median (IQR) values for water fluoride, MUFSG, and daily fluoride intake were 0.20 (IQR: 0.13-0.56) mg/L; 0.44 (0.28-0.70) mg/L and 4.82 (2.58-10.83) µg/kg/day, respectively. After adjustment for confounding variables, water fluoride concentration was associated with poorer infant visual acuity (B = -1.51; 95 % CI: -2.14,-0.88) and HRV as indicated by lower RMSSD (B = -1.60; 95 % CI: -2.74,-0.46) but not SDNN. Maternal fluoride intake was also associated with poorer visual acuity (B = -0.82; 95 % CI: -1.35,-0.29) and lower RMSSD (B = -1.22; 95 % CI: -2.15,-0.30). No significant associations were observed between MUFSG and visual acuity or HRV. CONCLUSION Fluoride in drinking water was associated with reduced visual acuity and alterations in cardiac autonomic function in infancy, adding to the growing body of evidence suggesting fluoride's developmental neurotoxicity.
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Affiliation(s)
- John E Krzeczkowski
- Department of Health Sciences, Brock University, St. Catharines, Ontario, Canada.
| | - Meaghan Hall
- Department of Psychology, York University, Toronto, Ontario, Canada
| | - Dave Saint-Amour
- Faculté de médecine - Département d'ophtalmologie, Université de Montréal, Montréal, Québec, Canada
| | - Youssef Oulhote
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sina, New York, NY, USA
| | - Taylor McGuckin
- Department of Psychology, York University, Toronto, Ontario, Canada
| | - Carly V Goodman
- Department of Psychology, York University, Toronto, Ontario, Canada
| | - Rivka Green
- Department of Psychology, York University, Toronto, Ontario, Canada
| | - Gina Muckle
- Centre de recherche du CHU de Québec-Université Laval, Québec, Canada; École de Psychologie, Université Laval, Québec, Québec, Canada
| | - Bruce Lanphear
- Faculty of Health Sciences, Simon Fraser University, Vancouver, British Columbia, Canada
| | - Christine Till
- Department of Psychology, York University, Toronto, Ontario, Canada
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3
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Goodman CV, Green R, DaCosta A, Flora D, Lanphear B, Till C. Sex difference of pre- and post-natal exposure to six developmental neurotoxicants on intellectual abilities: a systematic review and meta-analysis of human studies. Environ Health 2023; 22:80. [PMID: 37978510 PMCID: PMC10655280 DOI: 10.1186/s12940-023-01029-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 10/26/2023] [Indexed: 11/19/2023]
Abstract
BACKGROUND Early life exposure to lead, mercury, polychlorinated biphenyls (PCBs), polybromide diphenyl ethers (PBDEs), organophosphate pesticides (OPPs), and phthalates have been associated with lowered IQ in children. In some studies, these neurotoxicants impact males and females differently. We aimed to examine the sex-specific effects of exposure to developmental neurotoxicants on intelligence (IQ) in a systematic review and meta-analysis. METHOD We screened abstracts published in PsychINFO and PubMed before December 31st, 2021, for empirical studies of six neurotoxicants (lead, mercury, PCBs, PBDEs, OPPs, and phthalates) that (1) used an individualized biomarker; (2) measured exposure during the prenatal period or before age six; and (3) provided effect estimates on general, nonverbal, and/or verbal IQ by sex. We assessed each study for risk of bias and evaluated the certainty of the evidence using Navigation Guide. We performed separate random effect meta-analyses by sex and timing of exposure with subgroup analyses by neurotoxicant. RESULTS Fifty-one studies were included in the systematic review and 20 in the meta-analysis. Prenatal exposure to developmental neurotoxicants was associated with decreased general and nonverbal IQ in males, especially for lead. No significant effects were found for verbal IQ, or postnatal lead exposure and general IQ. Due to the limited number of studies, we were unable to analyze postnatal effects of any of the other neurotoxicants. CONCLUSION During fetal development, males may be more vulnerable than females to general and nonverbal intellectual deficits from neurotoxic exposures, especially from lead. More research is needed to examine the nuanced sex-specific effects found for postnatal exposure to toxic chemicals.
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Affiliation(s)
- Carly V Goodman
- Faculty of Health, York University, Toronto, M3J 1P3, ON, Canada.
| | - Rivka Green
- Faculty of Health, York University, Toronto, M3J 1P3, ON, Canada
| | - Allya DaCosta
- Faculty of Health, York University, Toronto, M3J 1P3, ON, Canada
| | - David Flora
- Faculty of Health, York University, Toronto, M3J 1P3, ON, Canada
| | - Bruce Lanphear
- Faculty of Health Sciences, Simon Fraser University, Vancouver, BC, Canada
| | - Christine Till
- Faculty of Health, York University, Toronto, M3J 1P3, ON, Canada
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Ramos AM, Herring AH, Villanger GD, Thomsen C, Sakhi AK, Cequier E, Aase H, Engel SM. The association of prenatal phthalates, organophosphorous pesticides, and organophosphate esters with early child language ability in Norway. ENVIRONMENTAL RESEARCH 2023; 225:115508. [PMID: 36813071 PMCID: PMC10071760 DOI: 10.1016/j.envres.2023.115508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/02/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Prenatal exposure to phthalates, organophosphate esters, and organophosphorous pesticides have been associated with neurodevelopmental deficits including language ability, however, few studies consider the effect of exposure mixtures and the potential longitudinal detriments over time. OBJECTIVE This study examines the influence of prenatal exposure to phthalates, organophosphate esters, and organophosphorous pesticides, on children's language ability from toddlerhood to the preschool period. METHODS This study includes 299 mother-child dyads from Norway in the Norwegian Mother, Father and Child Cohort Study (MoBa). Prenatal exposure to chemicals were assessed at 17 weeks' gestation, and child language skills were assessed at 18 months using the Ages and Stages Questionnaire communication subscale and at preschool age using the Child Development Inventory. We ran two structural equation models to examine the simultaneous influences of chemical exposures on parent-reported and teacher-reported child language ability. RESULTS Prenatal organophosphorous pesticides were negatively associated with preschool language ability through language ability at 18 months. Additionally, there was a negative association between low molecular weight phthalates and teacher-reported preschool language ability. There was no effect of prenatal organophosphate esters on child language ability at either 18 months or preschool age. CONCLUSIONS This study adds to the literature on prenatal exposure to chemicals and neurodevelopment and highlights the importance of developmental pathways in early childhood.
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Affiliation(s)
- Amanda M Ramos
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Amy H Herring
- Department of Statistical Science, Global Health, Biostatistics & Bioinformatics, Duke University, Durham, NC, USA
| | - Gro D Villanger
- Department of Child Health and Development, Division of Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Cathrine Thomsen
- Department of Environmental Health, Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Amrit K Sakhi
- Department of Environmental Health, Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Enrique Cequier
- Department of Environmental Health, Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Heidi Aase
- Department of Child Health and Development, Division of Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Stephanie M Engel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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Carroll SL, Mikhail ME, Burt SA. The development of youth antisocial behavior across time and context: A systematic review and integration of person-centered and variable-centered research. Clin Psychol Rev 2023; 101:102253. [PMID: 36758465 PMCID: PMC10073285 DOI: 10.1016/j.cpr.2023.102253] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/13/2022] [Accepted: 01/28/2023] [Indexed: 02/05/2023]
Abstract
BACKGROUND Trajectories of youth antisocial behavior (ASB) are characterized by continuity and change. Although numerous longitudinal studies have examined ASB, findings from person-centered and variable-centered research have not yet been integrated. The present paper integrates findings across statistical methods for a more comprehensive understanding of the development of ASB. Neighborhood disadvantage is considered as a core moderator. METHODS The study protocol was registered in the PROSPERO database of systematic reviews (registration number CRD42021255820). The PsycINFO and PubMed databases were examined (September 2022) to identify longitudinal studies of youth aggression and/or rule-breaking. Results from person-centered and variable-centered studies were integrated via narrative synthesis, and a systematic quality assessment was conducted. RESULTS Of 8227 studies identified, 136 met inclusion criteria. Our review indicated that rule-breaking trajectories were largely distinguished by differences in rate of change (i.e., slope), whereas aggression trajectories differed more by baseline level (i.e., intercept), particularly in childhood. For adolescents in disadvantaged neighborhoods, however, aggression trajectories differed by both intercept and slope. CONCLUSIONS The respective importance of the intercept and slope differed across dimensions of ASB, developmental stage, and neighborhood residence. Neighborhood disadvantage was associated with trajectories of aggression, consistent with developmental theories emphasizing the role of person-environment interactions.
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Affiliation(s)
- Sarah L Carroll
- Department of Psychology, Michigan State University, 316 Physics Rd #262, East Lansing, MI 48824, United States of America.
| | - Megan E Mikhail
- Department of Psychology, Michigan State University, 316 Physics Rd #262, East Lansing, MI 48824, United States of America
| | - S Alexandra Burt
- Department of Psychology, Michigan State University, 316 Physics Rd #262, East Lansing, MI 48824, United States of America
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Chen S, Xiao X, Song X, Qi Z, Li Y. Prediction of cord blood leptin on infant's neurodevelopment: A birth cohort in rural Yunnan, China. Psychoneuroendocrinology 2023; 148:105955. [PMID: 36442291 DOI: 10.1016/j.psyneuen.2022.105955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/17/2022] [Accepted: 10/17/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND Leptin, one of the peptide hormones secreted by adipocytes, plays a vital part in metabolism, but its role in early-life neurodevelopment remains poorly understood. METHODS We performed leptin analysis on 323 cord blood samples collected from a birth cohort in Yunnan rural area, China, and assessed infants' neurodevelopment at one year of age by the Bayley Scales of Infant and Toddler Development-Third Edition (BSID-III). Multiple linear regression and binary logistic regression models were used to explore the associations between cord blood leptin (CBL) concentrations and infants' neurodevelopment and the ability of CBL to predict the probabilities of infants' neurodevelopment delay. RESULTS Overall, 323 infants were included in this study. The median concentration of CBL was 4.7 ng/ml. The proportion of 1-year-old infants identified as being neurodevelopmental delayed was 34.5%, and delays in cognitive, language, and motor domains were 11.1%, 26.6%, and 13.9%, respectively. Multiple linear regression analyses manifested that the CBL concentration (log10-transformed) was positively correlated with the cognitive, language, and motor composite scores in infants, respectively (β = 7.76, 95%CI: 3.81-11.71; β = 6.73, 95%CI: 3.41-10.06; and β = 6.88, 95%CI: 3.48-10.29, respectively). Binary logistic regression analysis showed that compared with the higher, lower CBL (< 4.7 ng/ml) yielded a 1.41-fold increase in the risk of language development delay (OR = 2.41,95%CI: 1.42-4.09), a 1.49-fold higher risk of motor development delay (OR = 2.49, 95%CI: 1.25-4.96), and a 1.71-fold higher risk of neurodevelopment delay (OR = 2.71, 95%CI: 1.64-4.48) among infants. The prediction models showed that the probabilities of development delay in infants' language, motor, and neurodevelopment increased with the decline of CBL concentrations [rs = -0.63 (95% CI: -0.71, -0.56), rs = -0.46 (95% CI: -0.55, -0.38), rs = -0.55 (95% CI: -0.63, -0.46), respectively]. CONCLUSION The decline of CBL was associated with the decrease in infants' neurodevelopment scores at one year of age. CBL below 4.7 ng/ml may increase the risk of infants' neurodevelopment delay. The probabilities of infants' neurodevelopment delay increased with the decrease of CBL concentrations. CBL may be a predictor of the probability of children's neurodevelopment delay.
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Affiliation(s)
- Shuqi Chen
- School of Public Health, Kunming Medical University, Kunming, China; Ministry of Child Health, Longgang District Maternity & Child Healthcare Hospital of Shenzhen, Shenzhen, Guangdong, China
| | - Xia Xiao
- School of Public Health, Kunming Medical University, Kunming, China
| | - Xiaoxiao Song
- School of Public Health, Kunming Medical University, Kunming, China
| | - Zhiye Qi
- School of Public Health, Kunming Medical University, Kunming, China; Department of Pediatrics, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Yan Li
- School of Public Health, Kunming Medical University, Kunming, China.
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7
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Halabicky OM, Ji X, Gur RE, Gur RC, Yan C, Chen A, Liu J. Childhood lead exposure and sex-based neurobehavioral functioning in adolescence. Neurotoxicology 2022; 93:1-8. [PMID: 35988749 PMCID: PMC10433489 DOI: 10.1016/j.neuro.2022.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 08/16/2022] [Accepted: 08/16/2022] [Indexed: 10/15/2022]
Abstract
It is well documented that childhood lead exposure is associated with long-term decreases in intelligence quotients (IQ). Lesser known is the relationship with neurobehavioral domains, especially in adolescence. This study sought to identify cross-sectional and longitudinal associations between lead exposure and adolescent executive and visual-motor functioning and examine sex-based differences. Participants were 681 children from Jintan, China who had their blood lead levels (BLLs) assessed at age 3-5 years and 12 years old and neurobehavioral functioning assessed through the University of Pennsylvania Computerized Neurocognitive Battery (PennCNB) platform http://www.med.upenn.edu/bbl at 12 years old. Mean BLLs were 6.41 mcg/dl at age 3-5 years and 3.10 mcg/dl at 12. BLLs at 3-5 years and 12 years were used as predictors for the individual neurobehavioral domains in general linear models while controlling for father and mother occupation and education, residence location, age, and adolescent IQ. Models were run separately for males and females. In adjusted models, males BLLs at 3-5 years were associated with increased time to correctly complete tasks in multiple domains including abstraction/flexibility (β = 19.90, 95% CI( 4.26, 35.54) and spatial processing (β = 96.00, 95% CI 6.18, 185.82) at 12 years. For females in adjusted models, BLLs at 3-5 years were associated with increasing time to correctly complete tasks on the episodic memory domain task (β = 34.59, 95% CI 5.33, 63.84) at 12 years. Two adolescent cross-sectional relationships remained in the adjusted models for males only, suggesting a positive association between BLLs and increasing time for correct responses on the attentional domain task (β = 15.08, 95% CI 0.65, 29.51) and decreasing time for correct responses on the episodic memory task (β = -73.49, 95% CI -138.91, -8.06) in males at 12 years. These associations remained with and without controlling for IQ. These results suggest that lead exposure is associated with overall deficits in male and female neurobehavioral functioning, though in different domains and different timing of exposure.
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Affiliation(s)
| | - Xiaopeng Ji
- School of Nursing, University of Delaware, USA
| | - Raquel E Gur
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, USA
| | - Ruben C Gur
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, USA
| | - Chonghuai Yan
- Division of Environmental Science, Shanghai Institute for Pediatric Research, Shanghai Jiao Tong University, China
| | - Aimin Chen
- Department of Biostatistics Epidemiology and Informatics, University of Pennsylvania, USA
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Kordas K, Cantoral A, Desai G, Halabicky O, Signes-Pastor AJ, Tellez-Rojo MM, Peterson KE, Karagas MR. Dietary Exposure to Toxic Elements and the Health of Young Children: Methodological Considerations and Data Needs. J Nutr 2022; 152:2572-2581. [PMID: 36774123 PMCID: PMC10157815 DOI: 10.1093/jn/nxac185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 08/03/2022] [Accepted: 08/15/2022] [Indexed: 12/16/2022] Open
Abstract
Concerns have been raised regarding toxic-element (arsenic, cadmium, lead, and mercury) contamination of commercially available infant foods around the world. Young children are vulnerable to the effects of toxic elements, based on higher absorption levels and potentially poorer detoxification capacities. Toxic-element exposures in early life exact high societal costs, but it is unclear how much dietary exposure to these elements contributes to adverse health outcomes. Well-designed epidemiological studies conducted in different geographical and socioeconomic contexts need to estimate dietary toxicant exposure in young children and to determine whether causal links exist between toxicants in children's diets and health outcomes. This commentary outlines the methodological considerations and data needs to advance such research.
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Affiliation(s)
- Katarzyna Kordas
- Department of Epidemiology and Environmental Health, University at Buffalo, Buffalo NY, USA.
| | | | - Gauri Desai
- Department of Epidemiology and Environmental Health, University at Buffalo, Buffalo NY, USA
| | - Olivia Halabicky
- Department of Nutritional Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Antonio J Signes-Pastor
- Unidad de Epidemiología de la Nutrición, Universidad Miguel Hernández, Alicante, Spain; Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III (ISCIII), Madrid, Spain; Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), Alicante, Spain
| | - Martha M Tellez-Rojo
- Center for Nutrition and Health Research, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
| | - Karen E Peterson
- Department of Nutritional Sciences, University of Michigan, Ann Arbor, MI, USA; Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Margaret R Karagas
- Department of Epidemiology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
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9
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Shaffer RM, Forsyth JE, Ferraro G, Till C, Carlson LM, Hester K, Haddock A, Strawbridge J, Lanfear CC, Hu H, Kirrane E. Lead exposure and antisocial behavior: A systematic review protocol. ENVIRONMENT INTERNATIONAL 2022; 168:107438. [PMID: 35994796 DOI: 10.1016/j.envint.2022.107438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 07/19/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Lead exposure remains highly prevalent worldwide despite decades of research highlighting its link to numerous adverse health outcomes. In addition to well-documented effects on cognition, there is growing evidence of an association with antisocial behavior, including aggression, conduct problems, and crime. An updated systematic review on this topic, incorporating study evaluation and a developmental perspective on the outcome, can advance the state of the science on lead and inform global policy interventions to reduce exposure. OBJECTIVES We aim to evaluate the link between lead exposure and antisocial behavior. This association will be investigated via a systematic review of human epidemiological and experimental nonhuman mammalian studies. METHODS The systematic review protocol presented in this publication is informed by recommendations for the conduct of systematic reviews in toxicology and environmental health research (COSTER) and follows the study evaluation approach put forth by the U.S. EPA Integrated Risk Information System (IRIS) program. DATA SOURCES We will search the following electronic databases for relevant literature: PubMed, BIOSIS and Web of Science. Search results will be stored in EPA's Health and Environmental Research Online (HERO) database. STUDY ELIGIBILITY AND CRITERIA Eligible human epidemiological studies will include those evaluating any population exposed to lead at any lifestage via ingestion or inhalation exposure and considering an outcome of antisocial behavior based on any of the following criteria: psychiatric diagnoses (e.g., oppositional defiant disorder (ODD), conduct disorder (CD), disruptive behavior disorders (DBD)); violation of social norms (e.g., delinquency, criminality); and aggression. Eligible experimental animal studies will include those evaluating nonhuman mammalian studies exposed to lead via ingestion, inhalation, or injection exposure during any lifestage. The following outcomes will be considered relevant: aggression; antisocial behavior; and altered fear, anxiety, and stress response. STUDY APPRAISAL AND SYNTHESIS METHODS Screening will be conducted with assistance from an artificial intelligence application. Two independent reviewers for each data stream (human, animal) will screen studies with highest predicted relevance against pre-specified inclusion criteria at the title/abstract and full-text level. Study evaluation will be conducted using methods adapted from the U.S. EPA IRIS program. After data extraction, we will conduct a narrative review and quantitative meta-analysis on the human epidemiological studies as well as a narrative review of the experimental animal studies. We will evaluate the strength of each evidence stream separately and then will develop a summary evidence integration statement based on inference across evidence streams.
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Affiliation(s)
- Rachel M Shaffer
- US Environmental Protection Agency, Center for Public Health and Environmental Assessment, Washington, DC, and Research Triangle Park, NC, United States
| | - Jenna E Forsyth
- Stanford University, Woods Institute for the Environment, Stanford, CA, United States
| | - Greg Ferraro
- North Carolina State University, Raleigh, NC, United States
| | | | - Laura M Carlson
- US Environmental Protection Agency, Center for Public Health and Environmental Assessment, Washington, DC, and Research Triangle Park, NC, United States
| | - Kirstin Hester
- US Environmental Protection Agency, Center for Public Health and Environmental Assessment, Washington, DC, and Research Triangle Park, NC, United States
| | - Amanda Haddock
- US Environmental Protection Agency, Center for Public Health and Environmental Assessment, Washington, DC, and Research Triangle Park, NC, United States
| | - Jenna Strawbridge
- Oak Ridge Associated Universities, US Environmental Protection Agency, Center for Public Health and Environmental Assessment, Research Triangle Park, NC, United States
| | - Charles C Lanfear
- Nuffield College, University of Oxford, Oxford, England, United Kingdom
| | - Howard Hu
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Ellen Kirrane
- US Environmental Protection Agency, Center for Public Health and Environmental Assessment, Washington, DC, and Research Triangle Park, NC, United States.
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10
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A Call for Biomonitoring Systems in Latin America and the Caribbean: Considerations for Potentially Toxic Metals/Metalloids. Ann Glob Health 2022; 88:80. [PMID: 36185997 PMCID: PMC9479654 DOI: 10.5334/aogh.3637] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 06/10/2022] [Indexed: 11/21/2022] Open
Abstract
The Latin America and the Caribbean (LAC) region makes up 8.4% of the world’s population. Human biomonitoring (HBM) programs, which can shed light on population-level exposure to environmental contaminants such as toxic metals and thus, improve the health of the populations are inexistent in LAC countries. We call for the creation of HBM programs in the region and identify three viable design options for HBM at the individual level, through national surveys, newborn blood collection, and biobanks. We highlight some of challenges to the implementation of HBM programs, including financial and human resources, technical constrains (laboratory), sample, and data logistics. Finally, we provide the case studies of Brazil, Chile, Mexico, and Uruguay, to illustrate a range of responses to toxic metal exposure in non-occupational populations. Although different in many respects, the individual country responses share two commonalities: 1) academic centers drive the research to raise awareness of governmental entities; 2) reference levels are adapted from international norms rather than arising from the studied populations. Well-designed and sufficiently funded biomonitoring systems need to be established in each country of the LAC region. HBM programs are key to promoting human health by informing the public and contributing to policy processes that establish sustainable environmental controls and health prevention programs.
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Goodman CV, Bashash M, Green R, Song P, Peterson KE, Schnaas L, Mercado-García A, Martínez-Medina S, Hernández-Avila M, Martinez-Mier A, Téllez-Rojo MM, Hu H, Till C. Domain-specific effects of prenatal fluoride exposure on child IQ at 4, 5, and 6-12 years in the ELEMENT cohort. ENVIRONMENTAL RESEARCH 2022; 211:112993. [PMID: 35276192 PMCID: PMC9890727 DOI: 10.1016/j.envres.2022.112993] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 02/13/2022] [Accepted: 02/19/2022] [Indexed: 05/17/2023]
Abstract
OBJECTIVE Prenatal exposure to fluoride has been associated with adverse neurodevelopmental outcomes. However, the neuropsychological profile of fluoride's developmental neurotoxicity at low levels and the stability of this relationship across childhood has not been characterized. We investigated the longitudinal and domain specific effect of prenatal fluoride exposure on IQ among children ages 4, 5, and 6-12 years in the Early Life Exposures in Mexico to Environmental Toxicants (ELEMENT) cohort. METHODS We measured the average of maternal urinary fluoride at each trimester of pregnancy adjusted for creatinine (MUFCRE). Children were administered the McCarthy Scales of Children's Abilities at ages 4 (N = 386) and 5 (N = 308), and the Wechsler Abbreviated Scale of Intelligence at age 6-12 (N = 278). We used generalized estimating equation (GEE) models to estimate the population averaged effect of MUFCRE concentration on longitudinal General Cognitive Index (GCI)/Full-Scale IQ (FSIQ), Verbal IQ (VIQ), and Performance IQ (PIQ) scores (N = 348). We tested for possible interactions between MUFCRE and child sex as well as for MUFCRE and time point on children's IQ. All models controlled for relevant available covariates. RESULTS The mean/median MUFCRE concentration was 0.90/0.83 mg/L (SD = 0.39; IQR, 0.64-1.11 mg/L). A 0.5 mg/L increase in MUFCRE predicted an average 2.12-point decrease in GCI/FSIQ (95% CI: -3.49, -0.75) and 2.63-point decrease in PIQ (95% CI: -3.87, -1.40). MUFCRE was marginally associated with VIQ across time (B = -1.29, 95% CI: -2.60, 0.01). No interactions between MUFCRE and child sex or MUFCRE and time were observed. CONCLUSION The negative association between prenatal fluoride exposure and longitudinal IQ was driven by decrements in non-verbal intelligence (i.e. PIQ), suggesting that visual-spatial and perceptual reasoning abilities may be more impacted by prenatal fluoride exposure as compared to verbal abilities.
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Affiliation(s)
- Carly V Goodman
- Faculty of Health, York University, Toronto, Ontario, Canada
| | - Morteza Bashash
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Rivka Green
- Faculty of Health, York University, Toronto, Ontario, Canada
| | - Peter Song
- School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Karen E Peterson
- School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | | | | | | | | | | | | | - Howard Hu
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Christine Till
- Faculty of Health, York University, Toronto, Ontario, Canada
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A bioinformatics framework for targeted gene expression assay design: Application to in vitro developmental neurotoxicity screening in a rat model. Regul Toxicol Pharmacol 2022; 133:105211. [PMID: 35724854 DOI: 10.1016/j.yrtph.2022.105211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 05/05/2022] [Accepted: 06/13/2022] [Indexed: 11/23/2022]
Abstract
Brain development involves a series of intricately choreographed neuronal differentiation and maturation steps that are acutely vulnerable to interferences from chemical exposures. Many genes involved in neurodevelopmental processes show evolutionarily conserved expression patterns in mammals and may constitute useful indicators/biomarkers for the evaluation of potential developmental neurotoxicity. Based on these premises, this study developed a bioinformatics framework to guide the design of a gene expression-based in vitro developmental neurotoxicity assay targeting evolutionary conserved genes associated with neuronal differentiation and maturation in rat cerebellar granule cells (CGCs). Rat, mouse and human genes involved in neurodevelopment and presenting one-to-one orthology were selected and orthologous exons within these genes were identified. PCR primer sets were designed within these orthologous exons and their specificity was evaluated in silico. The performance and specificity of rat, mouse and human PCR primer sets were then confirmed experimentally. Finally, RT-qPCR analyses in CGCs exposed in vitro to well-known neurotoxicants (Chlorpyrifos and Chlorpyrifos oxon) uncovered perturbations of expression levels for most of the selected genes. This bioinformatics framework for gene and target sequence selection may facilitate the identification of transcriptional biomarkers for developmental neurotoxicity assays and the comparison of gene expression data across experimental models from different mammalian species.
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Nedelescu M, Stan M, Ciobanu AM, Bălălău C, Filippini T, Baconi D. Attention deficit among preschool and school-aged children living near former metal-processing plants in Romania. ENVIRONMENTAL RESEARCH 2022; 208:112689. [PMID: 34999026 DOI: 10.1016/j.envres.2022.112689] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 12/14/2021] [Accepted: 01/04/2022] [Indexed: 05/06/2023]
Abstract
Industrial areas affected by high and long-term heavy metal pollution have a great impact on health of the resident population. Children represent a group at high-risk with an increased susceptibility to chronic heavy metal intoxication. Our work included the assessment of attention particularities through a case-control study in pre-school and school-aged children (4-6 years and 8-11 years) from two study areas, Copşa Mică and Zlatna, compared to a non-polluted locality with no history of heavy metal pollution. Copşa Mică and Zlatna are two of the most polluted heavy metals regions in Romania due to non-ferrous metallurgy for a long period of time. Recruitment of participants was made by a random selection of an entire class for each age within the schools and kindergartens from the study areas (Copşa Mică and Zlatna) and from the non-polluted region. Interpretation of data was performed using statistical analysis (ANOVA and Student's t-test). Preschool children (4-6 years) were tested using Wechsler Preschool and Primary Scale of Intelligence (WPPSI) tests, Animal House and labyrinth samples. The results of the attention tests applied to pre-school children were lower in the study areas compared to the control group, but no statistical differences were found. The results of the attention tests applied to children aged between 8 and 11 years (Toulouse-Pieron test and Traffic light test) indicate lower average scores within the study groups from polluted areas, compared to the control group. Differences with statistically significance were registered for the 8 years age group (p = 0.037). In these areas efficient strategies and precise intervention measures are needed in order to limit or remove the heavy metal exposure and protect the human health, especially the groups exposed to a high level of risk.
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Affiliation(s)
- Mirela Nedelescu
- (")Carol Davila" University of Medicine and Pharmacy, Faculty of Medicine, 8 Eroii Sanitari Blvd, Bucharest, Romania; National Institute of Public Health, Department of Food Hygiene and Nutrition, 1-3 Dr. Leonte Street, Bucharest, Romania
| | - Miriana Stan
- "Carol Davila" University of Medicine and Pharmacy "Carol Davila", Faculty of Pharmacy, 6 Traian Vuia Street, Bucharest, Romania.
| | - Anne-Marie Ciobanu
- "Carol Davila" University of Medicine and Pharmacy "Carol Davila", Faculty of Pharmacy, 6 Traian Vuia Street, Bucharest, Romania
| | - Cristian Bălălău
- (")Carol Davila" University of Medicine and Pharmacy, Faculty of Medicine, 8 Eroii Sanitari Blvd, Bucharest, Romania
| | - Tommaso Filippini
- CREAGEN - Environmental, Genetic and Nutritional Epidemiology Research Center, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Campi 287, Modena, Italy
| | - Daniela Baconi
- "Carol Davila" University of Medicine and Pharmacy "Carol Davila", Faculty of Pharmacy, 6 Traian Vuia Street, Bucharest, Romania
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Min MO, Lewis BA, Minnes S, Gonzalez-Pons KM, Kim JY, Singer LT. Preschool blood lead levels, language competency, and substance use in adolescence. ENVIRONMENTAL RESEARCH 2022; 206:112273. [PMID: 34710438 PMCID: PMC8810688 DOI: 10.1016/j.envres.2021.112273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/22/2021] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Elevated lead levels in children are a persistent public health problem, particularly in urban areas in the United States, yet few prospective studies have examined the association of childhood lead levels with substance use in adolescence. OBJECTIVES To determine the association of early lead levels with adolescent substance use and whether childhood IQ, language skills, and externalizing (aggressive and disruptive) behavior mediate the association, controlling for confounding biological and environmental factors. METHODS The participants (N = 265) were a subsample of a prospective birth cohort study on the developmental effects of prenatal cocaine exposure in the Midwest United States. Blood lead levels (BLL) were assessed at age 4, IQ at age 11, language skills and externalizing behavior at age 12, and substance (alcohol, tobacco, marijuana) use and substance use-related problems at age 15. Biologic assays (hair, urine, bloodspots), along with self-report, were utilized to determine adolescent substance use. Path analyses were conducted to examine the direct and indirect associations of BLL with adolescent substance use. RESULTS The children's mean BLL at 4 years of age was 7.07 (SD = 4.12) μg/dL. Approximately 31% of adolescents used tobacco or marijuana, 40% used alcohol, and 23% reported experiencing substance use-related problems at age 15.7 (SD = 0.28). Elevated BLL was related to a higher likelihood of substance use. Childhood language skills fully mediated the relationship of BLL with substance use-related problems. IQ was related to neither substance use nor substance use-related problems. DISCUSSION Elevated BLL in preschool years is a risk factor for adolescent substance use and related problems. Early screening and intervention for language impairment may reduce substance use-related problems.
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Affiliation(s)
- Meeyoung O Min
- College of Social Work, University of Utah, United States.
| | - Barbara A Lewis
- Department of Psychological Sciences, Case Western Reserve University, United States
| | - Sonia Minnes
- Jack, Joseph and Morton Mandel School of Applied Social Sciences, Case Western Reserve University, United States
| | | | - June-Yung Kim
- Department of Social Work, University of North Dakota, United States
| | - Lynn T Singer
- Departments of Population and Quantitative Health Sciences, Psychological Sciences, Psychiatry and Pediatrics, Case Western Reserve University, United States
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Lin S, Ali MU, Zheng C, Cai Z, Wong MH. Toxic chemicals from uncontrolled e-waste recycling: Exposure, body burden, health impact. JOURNAL OF HAZARDOUS MATERIALS 2022; 426:127792. [PMID: 34802823 DOI: 10.1016/j.jhazmat.2021.127792] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 10/30/2021] [Accepted: 11/11/2021] [Indexed: 06/13/2023]
Abstract
Uncontrolled electronic-waste (e-waste) recycling processes have induced serious environmental pollution and human health impacts. This paper reviewed studies on the wide range of toxic chemicals through the use of primitive recycling techniques, their transfer to various ecological compartments, and subsequent health impacts. Results indicated that local food items were heavily polluted by the pollutants emitted, notably heavy metals in vegetables, rice, fish and seafood, and persistent organic pollutants (POPs) in livestock. Dietary exposure is the most important exposure pathway. The associations between exposure to e-waste and high body burdens of these pollutants were evident. It seems apparent that toxic chemicals emitted from e-waste activities are causing a number of major illnesses related to cardiovascular, digestive and respiratory systems, according to the information provided by a local hospital (Taizhou, an e-waste recycling hot spot in China). More epidemiological data should be made available to the general public. It is envisaged that there are potential dangers of toxic chemicals passing on to the next generation via placental transfer and lactation. There is a need to monitor the development and health impacts of infants and children, born and brought up in the e-waste sites.
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Affiliation(s)
- Siyi Lin
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen 518055, China; State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Muhammad Ubaid Ali
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chunmiao Zheng
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zongwei Cai
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Ming Hung Wong
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen 518055, China; Consortium on Health, Environment, Education and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Hong Kong, China.
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16
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Liu J, Portnoy J, Raine A, Gladieux M, McGarry P, Chen A. Blood lead levels mediate the relationship between social adversity and child externalizing behavior. ENVIRONMENTAL RESEARCH 2022; 204:112396. [PMID: 34801542 PMCID: PMC10117419 DOI: 10.1016/j.envres.2021.112396] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/12/2021] [Accepted: 11/13/2021] [Indexed: 06/01/2023]
Abstract
BACKGROUND/AIMS The association between social adversity and externalizing behavioral problems in children is well-documented. What is much less researched are biological mechanisms that may mediate such relationships. This study examines the hypothesis that low blood lead mediates the relationship between social adversity and child externalizing behavior problems. METHODS In this cross-sectional study, participants were 131 children aged 11-12 years (mean = 11.90) from Philadelphia, US. A venous fasting blood sample was taken and analyzed for blood lead levels. A social adversity index was calculated based on 10 total indicators derived from a psychosocial interview of the parent and official neighborhood data, while child behavior outcomes (internalizing and externalizing behavior) were assessed using both parent-report and child self-report. RESULTS The mean blood lead level was 2.20 μg/dL. Both relatively higher blood lead levels and higher social adversity scores were associated with higher levels of parent-reported and child self-reported externalizing behaviors. Additionally, blood lead mediated the relationship between social adversity and child-reported externalizing behavior (Indirect effect: B = 0.03, 95% CI: 0.004, 0.09) and partially mediated the relationship between social adversity and parent-reported externalizing behavior (Indirect Effect: B = 0.03, 95% CI: 0.01, 0.07). CONCLUSION To our knowledge, this study is the first to suggest that blood lead levels play a mediating role in the relationship between externalizing behavior problems and social adversity. Findings have potentially important implications for public health and environmental regulation as well as understanding biological mechanisms that link social inequality with health outcomes, especially in youth from low-income, urban areas.
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Affiliation(s)
- Jianghong Liu
- University of Pennsylvania, School of Nursing 418 Curie Blvd., Claire M. Fagin Hall, Philadelphia, PA, 19104, USA.
| | - Jill Portnoy
- University of Massachusetts Lowell, School of Criminology and Justice Studies, 113 Wilder Street, Lowell, MA, 01854, USA.
| | - Adrian Raine
- University of Pennsylvania, Departments of Criminology, Psychiatry, and Psychology, 3718 Locust Walk, McNeil Building, Philadelphia, PA, 19104, USA.
| | - Margaret Gladieux
- University of Pennsylvania, School of Nursing 418 Curie Blvd., Claire M. Fagin Hall, Philadelphia, PA, 19104, USA.
| | - Presley McGarry
- University of Massachusetts Lowell, School of Criminology and Justice Studies, 113 Wilder Street, Lowell, MA, 01854, USA.
| | - Aimin Chen
- University of Pennsylvania, Department of Biostatistics, Epidemiology and Informatics, 423 Guardian Drive, Blockley Hall, Philadelphia, PA, 19104, USA.
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Sears CG, Lanphear BP, Xu Y, Chen A, Yolton K, Braun JM. Identifying periods of heightened susceptibility to lead exposure in relation to behavioral problems. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2022; 32:1-9. [PMID: 34728761 PMCID: PMC8776587 DOI: 10.1038/s41370-021-00389-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 05/11/2023]
Abstract
BACKGROUND Lead exposure is associated with behavioral problems in children, but the age(s) of greatest susceptibility to low-level lead exposure is unknown. OBJECTIVE We evaluated the association of repeated blood lead concentrations with parent-reported behaviors to identify periods of heightened susceptibility during infancy and childhood (HOME Study; Cincinnati, OH; 2003-2006; n = 244). METHODS We quantified lead in whole blood samples (ages 1, 2, 3, 4, 5, and 8 years) and assessed behavior using the Behavioral Assessment System for Children-2 (BASC-2; ages 2, 3, 4, 5, and 8 years). We used multiple informant models and modified Poisson regression to estimate covariate-adjusted associations of ln-transformed blood lead concentrations with continuous BASC-2 T-scores and the relative risk of behavior scores classified as at-risk or clinically significant, respectively. RESULTS We observed trends indicating that higher blood lead concentrations at all ages were adversely associated with scores on behavioral scales. On the Externalizing Problems and Adaptive Skills scales, these associations were strongest for blood lead concentrations at age 8 years (β = 3.1-point; 95% CI = 0.7, 5.4 and β = -2.2-point; 95% CI = -4.9, 0.5, respectively) compared with other ages. Overall, higher blood lead concentrations were associated with elevated risk of behavior scores classified as at-risk or clinically significant on the Adaptive Skills, Behavioral Symptom Index, and Externalizing Problems scales. SIGNIFICANCE Contemporary levels of lead exposure during the first 8 years of life were associated with ADHD-related behaviors, specifically aggression, hyperactivity, and conduct problems. IMPACT STATEMENT Our results highlight the importance of primary lead prevention across childhood.
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Affiliation(s)
- Clara G Sears
- Department of Epidemiology, Brown University, Providence, RI, USA.
- Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, USA.
| | - Bruce P Lanphear
- Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Yingying Xu
- Division of General and Community Pediatrics, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Aimin Chen
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Kimberly Yolton
- Department of Pediatrics, Cincinnati Children's Hospital, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Joseph M Braun
- Department of Epidemiology, Brown University, Providence, RI, USA
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Sternberg RJ. AWOKE: A theory of representation and process in intelligence as adaptation to the environment. PERSONALITY AND INDIVIDUAL DIFFERENCES 2021. [DOI: 10.1016/j.paid.2021.111108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Environment in Children's Health: A New Challenge for Risk Assessment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph181910445. [PMID: 34639744 PMCID: PMC8507725 DOI: 10.3390/ijerph181910445] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/27/2021] [Accepted: 10/01/2021] [Indexed: 11/17/2022]
Abstract
In the last few years, many studies have focused on the effects of environmental contaminant exposure during the prenatal period or infancy as predictors of health outcomes in the future. In these time windows, due to their rapid growth, and physiologic and metabolic development, we can observe a higher vulnerability to the effects of environment, with respect to adulthood. The evidence of possible influences, partly mediated by epigenetic mechanisms, involve neurobehavioral responses and immune, endocrine, and respiratory systems, acting directly on the child or indirectly when mediated by placental transfer or breast feeding. In particular, due to a greater intake of air, food, and fluids relative to body weight, crawling behaviors and short stature, the risk of excessive exposure is greater in children. However, data on the long-term implications of early exposures are scarce. Additionally, so that physicians and institutions for child care and assistance of pregnant women can take actions to counteract the effects of chemical pollution (i.e., by educational opportunities), a risk assessment perspective that responds to the biocomplexity of the human being is needed. The present paper provides an overview of physiologic and behavioral characteristics during the perinatal period and in childhood, suggesting in a more integrated way, the need of a new risk-assessment approach to managing chronic disease in pediatric patients.
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Rygiel CA, Goodrich JM, Solano-González M, Mercado-García A, Hu H, Téllez-Rojo MM, Peterson KE, Dolinoy DC. Prenatal Lead (Pb) Exposure and Peripheral Blood DNA Methylation (5mC) and Hydroxymethylation (5hmC) in Mexican Adolescents from the ELEMENT Birth Cohort. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:67002. [PMID: 34152198 PMCID: PMC8216410 DOI: 10.1289/ehp8507] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
BACKGROUND Gestational lead (Pb) exposure can adversely affect offspring health through multiple mechanisms, including epigenomic alterations via DNA methylation (5mC) and hydroxymethylation (5hmC), an intermediate in oxidative demethylation. Most current methods do not distinguish between 5mC and 5hmC, limiting insights into their individual roles. OBJECTIVE Our study sought to identify the association of trimester-specific (T1, T2, T3) prenatal Pb exposure with 5mC and 5hmC levels at multiple cytosine-phosphate-guanine sites within gene regions previously associated with prenatal Pb (HCN2, NINJ2, RAB5A, TPPP) in whole blood leukocytes of children ages 11-18 years of age. METHODS Participants from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) birth cohorts were selected (n=144) for pyrosequencing analysis following oxidative or standard sodium bisulfite treatment. This workflow directly quantifies total methylation (5mC+5hmC) and 5mC only; 5hmC is estimated by subtraction. RESULTS Participants were 51% male, and mean maternal blood lead levels (BLL) were 6.43±5.16μg/dL in Trimester 1 (T1), 5.66±5.21μg/dL in Trimester 2 (T2), and 5.86±4.34μg/dL in Trimester 3 (T3). In addition, 5hmC levels were calculated for HCN2 (mean±standard deviation(SD), 2.08±4.18%), NINJ2 (G/C: 2.01±5.95; GG: 0.90±3.97), RAB5A (0.66±0.80%), and TPPP (1.11±6.67%). Furthermore, 5mC levels were measured in HCN2 (81.3±9.63%), NINJ2 (heterozygotes: 38.6±7.39%; GG homozygotes: 67.3±9.83%), RAB5A (1.41±1.21%), and TPPP (92.5±8.03%). Several significant associations between BLLs and 5mC/5hmC were identified: T1 BLLs with 5mC in HCN2 (β=-0.37, p=0.03) and 5hmC in NINJ2 (β=0.49, p=0.003); T2 BLLs with 5mC in HCN2 (β=0.37, p=0.03) and 5hmC in NINJ2 (β=0.27, p=0.008); and T3 BLLs with 5mC in HCN2 (β=0.50, p=0.01) and NINJ2 (β=-0.35, p=0.004) and 5hmC in NINJ2 (β=0.45, p<0.001). NINJ2 5mC was negatively correlated with gene expression (Pearson r=-0.5, p-value=0.005), whereas 5hmC was positively correlated (r=0.4, p-value=0.04). DISCUSSION These findings suggest there is variable 5hmC in human whole blood and that prenatal Pb exposure is associated with gene-specific 5mC and 5hmC levels at adolescence, providing evidence to consider 5hmC as a regulatory mechanism that is responsive to environmental exposures. https://doi.org/10.1289/EHP8507.
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Affiliation(s)
- Christine A. Rygiel
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
| | - Jaclyn M. Goodrich
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
| | | | | | - Howard Hu
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | | | - Karen E. Peterson
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
| | - Dana C. Dolinoy
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
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Albores-Garcia D, McGlothan JL, Guilarte TR. Early-life lead exposure and neurodevelopmental disorders. CURRENT OPINION IN TOXICOLOGY 2021; 26:22-27. [PMID: 34013137 DOI: 10.1016/j.cotox.2021.03.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lead (Pb2+) exposure is a global public health problem of major proportion with an alarming number of children with blood Pb2+ levels > 10 >g/dL, twice the current CDC reference level for Pb2+ exposure. Mounting evidence from population-based studies suggests an association between chronic early life Pb2+ exposure (CELLE) and psychiatric disorders, specifically schizophrenia (SZ). Preclinical studies suggest a common mechanism in the pathophysiology of CELLE and SZ, NMDA receptor hypofunction. Here we describe human and experimental animal studies providing the evidence for such an association. Further, recent preclinical studies indicate that Pb2+-induced changes in neurotransmitter receptors that mediate the action(s) of drugs of abuse are increased in brain regions associated with addiction circuits in adolescence, a period of increased susceptibility to drug use and abuse and expression of psychiatric disease in humans. In summary, the relationship between the global burden of childhood Pb2+ exposure and the latent onset of psychiatric disorders and predisposition to drug use requires further investigations in human populations.
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Affiliation(s)
- D Albores-Garcia
- Brain, Behavior & the Environment Program Department of Environmental Health Sciences Robert Stempel College of Public Health & Social Work Florida International University Miami, FL 33199, United States
| | - J L McGlothan
- Brain, Behavior & the Environment Program Department of Environmental Health Sciences Robert Stempel College of Public Health & Social Work Florida International University Miami, FL 33199, United States
| | - T R Guilarte
- Brain, Behavior & the Environment Program Department of Environmental Health Sciences Robert Stempel College of Public Health & Social Work Florida International University Miami, FL 33199, United States
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Payne-Sturges DC, Cory-Slechta DA, Puett RC, Thomas SB, Hammond R, Hovmand PS. Defining and Intervening on Cumulative Environmental Neurodevelopmental Risks: Introducing a Complex Systems Approach. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:35001. [PMID: 33688743 PMCID: PMC7945198 DOI: 10.1289/ehp7333] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 02/05/2021] [Accepted: 02/10/2021] [Indexed: 05/21/2023]
Abstract
BACKGROUND The combined effects of multiple environmental toxicants and social stressor exposures are widely recognized as important public health problems contributing to health inequities. However cumulative environmental health risks and impacts have received little attention from U.S. policy makers at state and federal levels to develop comprehensive strategies to reduce these exposures, mitigate cumulative risks, and prevent harm. An area for which the inherent limitations of current approaches to cumulative environmental health risks are well illustrated is children's neurodevelopment, which exhibits dynamic complexity of multiple interdependent and causally linked factors and intergenerational effects. OBJECTIVES We delineate how a complex systems approach, specifically system dynamics, can address shortcomings in environmental health risk assessment regarding exposures to multiple chemical and nonchemical stressors and reshape associated public policies. DISCUSSION Systems modeling assists in the goal of solving problems by improving the "mental models" we use to make decisions, including regulatory and policy decisions. In the context of disparities in children's cumulative exposure to neurodevelopmental stressors, we describe potential policy insights about the structure and behavior of the system and the types of system dynamics modeling that would be appropriate, from visual depiction (i.e., informal maps) to formal quantitative simulation models. A systems dynamics framework provides not only a language but also a set of methodological tools that can more easily operationalize existing multidisciplinary scientific evidence and conceptual frameworks on cumulative risks. Thus, we can arrive at more accurate diagnostic tools for children's' environmental health inequities that take into consideration the broader social and economic environment in which children live, grow, play, and learn. https://doi.org/10.1289/EHP7333.
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Affiliation(s)
- Devon C. Payne-Sturges
- Maryland Institute for Applied Environmental Health, University of Maryland School of UMD Public Health, College Park, Maryland, USA
| | | | - Robin C. Puett
- Maryland Institute for Applied Environmental Health, University of Maryland School of UMD Public Health, College Park, Maryland, USA
| | - Stephen B. Thomas
- Department of Health Policy and Management and Maryland Center for Health Equity, University of Maryland School of Public Health, College Park, Maryland, USA
| | - Ross Hammond
- Brown School of Social Work, Washington University, St. Louis, Missouri, USA
- Center on Social Dynamics and Policy, The Brookings Institution, Washington, DC, USA
| | - Peter S. Hovmand
- Center for Community Health Integration, Case Western Reserve University, Cleveland, Ohio, USA
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Azar N, Booij L, Muckle G, Arbuckle TE, Séguin JR, Asztalos E, Fraser WD, Lanphear BP, Bouchard MF. Prenatal exposure to polybrominated diphenyl ethers (PBDEs) and cognitive ability in early childhood. ENVIRONMENT INTERNATIONAL 2021; 146:106296. [PMID: 33395941 DOI: 10.1016/j.envint.2020.106296] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/17/2020] [Accepted: 11/19/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Prenatal exposure to polybrominated diphenyl ethers (PBDEs) has been associated with adverse neurodevelopmental outcomes in children, but evidence remains mixed regarding sex differences in this association. OBJECTIVE To examine the prospective association between prenatal PBDE exposure and cognitive ability in young children, as well as potential sex differences. METHODS The study was conducted in a multi-site Canadian pregnancy cohort recruited in 2008-11. PBDEs were measured in maternal plasma samples collected early in pregnancy. Cognitive ability was assessed using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) in children at age 3 years (mean = 3.4). Multiple linear regression was used to analyze the association between maternal PBDE plasma concentrations (lipid-standardized and log10-transformed) and Verbal, Performance, and Full Scale IQ scores on the whole sample and stratified by sex, adjusting for confounders. RESULTS The sample was composed of 592 children (291 boys and 301 girls). A tenfold increase in maternal blood PBDE concentration (sum of BDE-47, -99, -100, and -153) was associated with lower Full Scale scores in boys (-3.4 points; 95% CI: -7.0, 0.1), after adjusting for confounders. BDE-47 was the congener with the highest concentrations in maternal blood and a tenfold increase in exposure was associated with significantly lower Full Scale IQ scores in boys (-4.4 points; 95% CI: -7.9, -0.9), after adjusting for confounders. Verbal and Performance IQ scores were similarly associated with PBDE exposure. Maternal blood PBDE concentrations were not associated with IQ scores in girls. CONCLUSIONS Prenatal exposure to background levels of PBDEs, especially BDE-47, was associated with lower IQ scores in boys, but not in girls. Our results support that exposure to PBDEs during early development may be sex-dependent and detrimental to a child's neurodevelopmental trajectory.
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Affiliation(s)
- Naomi Azar
- Department of Psychology, Concordia University, Montréal, Québec, Canada; Sainte-Justine University Hospital Research Center, Québec, Canada
| | - Linda Booij
- Department of Psychology, Concordia University, Montréal, Québec, Canada; Sainte-Justine University Hospital Research Center, Québec, Canada; Department of Psychiatry and Addictology, Université de Montréal, Montréal, Québec, Canada
| | - Gina Muckle
- School of Psychology, Université Laval, Ville de Québec, Québec, Canada
| | - Tye E Arbuckle
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada
| | - Jean R Séguin
- Sainte-Justine University Hospital Research Center, Québec, Canada; Department of Psychiatry and Addictology, Université de Montréal, Montréal, Québec, Canada
| | - Elizabeth Asztalos
- Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
| | - William D Fraser
- Sainte-Justine University Hospital Research Center, Québec, Canada; Centre de recherche du CHUS (CHU de Sherbrooke), Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Bruce P Lanphear
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada; BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
| | - Maryse F Bouchard
- Sainte-Justine University Hospital Research Center, Québec, Canada; Department of Environmental and Occupational Health, School of Public Health of the University of Montreal, Montréal, Québec, Canada.
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(Ascorb)ing Pb Neurotoxicity in the Developing Brain. Antioxidants (Basel) 2020; 9:antiox9121311. [PMID: 33371438 PMCID: PMC7767447 DOI: 10.3390/antiox9121311] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 12/21/2022] Open
Abstract
Lead (Pb) neurotoxicity is a major concern, particularly in children. Developmental exposure to Pb can alter neurodevelopmental trajectory and has permanent neuropathological consequences, including an increased vulnerability to further stressors. Ascorbic acid is among most researched antioxidant nutrients and has a special role in maintaining redox homeostasis in physiological and physio-pathological brain states. Furthermore, because of its capacity to chelate metal ions, ascorbic acid may particularly serve as a potent therapeutic agent in Pb poisoning. The present review first discusses the major consequences of Pb exposure in children and then proceeds to present evidence from human and animal studies for ascorbic acid as an efficient ameliorative supplemental nutrient in Pb poisoning, with a particular focus on developmental Pb neurotoxicity. In doing so, it is hoped that there is a revitalization for further research on understanding the brain functions of this essential, safe, and readily available vitamin in physiological states, as well to justify and establish it as an effective neuroprotective and modulatory factor in the pathologies of the nervous system, including developmental neuropathologies.
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Inaction on Lead Despite the Relevant Knowledge: Predictors, Covariates, and Outreach Implications. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17249391. [PMID: 33333985 PMCID: PMC7765355 DOI: 10.3390/ijerph17249391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/06/2020] [Accepted: 12/11/2020] [Indexed: 11/18/2022]
Abstract
Testing residential soil and paint for lead provides actionable information. By showing where and how much lead exists on the residence, it allows one to quantify risk and determine the best ways to reduce exposure along with the corresponding health and financial costs. For these reasons, several federal and state programs offer outreach to audiences on the benefits of testing residential soil and paint for lead. Not all individuals who know about lead’s adverse health effects, however, test their residence for lead, potentially limiting the actionable information that could have helped to reduce their exposure. Such individuals represent a challenge to outreach programs and the broader public health objectives. There is, thus, a need to understand who such individuals are and why they behave this way, allowing us to develop a specialized outreach program that addresses the problem by targeting the relevant sub-population. Using survey data, we quantitatively determine the profiles of individuals who, despite knowing about lead’s adverse health effects, are unlikely to test their residence for lead, finding statistically significant socio-economic predictors and behavioral covariates. We also find a geographic component to it, further helping outreach professionals learn how to allocate their limited resources.
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Ntantu Nkinsa P, Muckle G, Ayotte P, Lanphear BP, Arbuckle TE, Fraser WD, Bouchard MF. Organophosphate pesticides exposure during fetal development and IQ scores in 3 and 4-year old Canadian children. ENVIRONMENTAL RESEARCH 2020; 190:110023. [PMID: 32777276 DOI: 10.1016/j.envres.2020.110023] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 05/22/2023]
Abstract
BACKGROUND Organophosphate pesticides are widely used in agriculture and for other purposes, leading to ubiquitous exposure in human populations. Some studies reported cognitive deficits in children exposed prenatally to organophosphate pesticides, but findings from recent studies were inconsistent. Furthermore, recent biomonitoring studies suggest exposure levels have decreased. Hence, the risks from current prenatal exposure to organophosphate pesticides for child neurodevelopment are uncertain. Furthermore, sex-differences also remain to be better documented in relation to potential neurodevelopmental effects. OBJECTIVE To examine the association between prenatal exposure to organophosphate pesticides and IQ scores among boys and girls living in several major Canadian cities. METHODS We used data from the MIREC cohort (Maternal-Infant Research on Environmental Chemicals). Women were recruited in 2008-2011 from 10 Canadian cities during their first trimester of pregnancy, and urine spot samples were collected for measurement of three dimethyl alkyl phosphate (DMAP) and three diethyl alkyl phosphate (DEAP) metabolites. When children were 3-4 years of age, we used the Wechsler Preschool and Primary Scales of Intelligence-III (WPPSI-III) to assess cognitive ability of children from 6 out of the 10 cities (Halifax, Hamilton, Kingston, Montreal, Toronto, and Vancouver). We analysed the association between maternal exposure to organophosphate pesticides (DMAP and DEAP urinary metabolites) and children's IQ scores with generalized estimating equations (GEEs) to take into account the clustered-data resulting from the six study sites. All analyses were sex-stratified (n = 296 boys and 311 girls). RESULTS The participants were predominantly well-educated, white women, with a relatively high household income. Children had a mean age of 3.4 years at the moment of IQ assessment (range, 3.0-4.1 years). In girls, there was no association between IQ scores and DEAPs or DMAPs. Higher concentrations of DEAPs were significantly associated with poorer Verbal IQ scores (for a 10-fold increase in concentrations, -6.28; 95% CIs, -12.13, -0.43) in boys. The association for Performance IQ in boys also indicated poorer scores with higher DEAP concentrations, but the confidence intervals included the null value (-4.05; 95% CIs, -10.19, 2.10). The relation between DMAPs and IQ scores in boys was also negative, but association estimates were small and not significant. CONCLUSION Urinary metabolites of organophosphate pesticides were not associated with IQ in girls, but we observed that higher maternal urinary DEAPs were associated with poorer Verbal IQ in boys. However, exposure misclassification may be an issue as only one urine sample per woman was analysed. The present study contributes to the accumulating evidence linking exposure to organophosphate pesticides during fetal development with poorer cognitive function in children, bringing data on the risks in a context of low exposure levels encountered in primarily urban populations from Canada.
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Affiliation(s)
- Patrick Ntantu Nkinsa
- Department of Environmental and Occupational Health, School of Public Health, Université de Montreal, Montréal, Québec, Canada.
| | - Gina Muckle
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, École de Psychologie, Université Laval, Quebec, Québec, Canada.
| | - Pierre Ayotte
- Centre de Toxicologie du Québec, Institut National de Santé Publique du Québec, Québec, Canada.
| | - Bruce P Lanphear
- Faculty of Health Sciences, Simon Fraser University, Vancouver, British Columbia, Canada.
| | - Tye E Arbuckle
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada.
| | - William D Fraser
- Department of Obstetrics and Gynecology, Université de Sherbrooke, Centre Hospitalier Universitaire de Sherbrooke, Québec, Canada.
| | - Maryse F Bouchard
- Department of Environmental and Occupational Health, School of Public Health, Université de Montreal; CHU Sainte-Justine Research Centre Mother and Child University Hospital Center, Montréal, Quebec, Canada.
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Kim J, Yoon K. Municipal Residence Level of Long-Term PM 10 Exposure Associated with Obesity among Young Adults in Seoul, Korea. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E6981. [PMID: 32987676 PMCID: PMC7579278 DOI: 10.3390/ijerph17196981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 11/16/2022]
Abstract
BACKGROUND long-term effects of ambient pollutants used to be defined in cohort studies using biomarkers. Health effects on young adults from long-term exposure to particulate matters (PM) in residential ambiance have received less attention. METHODS using the data of population-representative aged 19-29 in Seoul, the relationship between obesity and PM10 levels of the living district was examined. We defined obesity as Body Mass Index (BMI) 25 kg/m2 and more. Survey logistic regression was conducted according to individual residence periods in the current municipality. Individual characteristics were adjusted overall and were age-specific; aged 19-24 and 25-29. RESULTS study population was 3655 (1680 (46%) men and 1933 aged 19-24 (52.9%)) individuals. Relationship between length of residence in municipalities with a greater level of PM10 from 2001-2005 and obesity was increased over the residing period; 10 years ≤ (odds ratio (OR) 1.071, 95% confidence interval (CI) 0.969-1.185), 15 years ≤ (1.120, 1.006-1.247), and 20 years ≤ (1.158, 1.034-1.297) in aged 19-29. Age-specific effects showed slight differences. CONCLUSIONS Although PM10 levels are currently decreasing, higher levels of PM10 exposure in the residential area during the earlier lifetime may contribute to obesity increase among young adults.
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Affiliation(s)
- Jayeun Kim
- Institute of Health and Environment, Seoul National University, Seoul 08826, Korea;
- Graduate School of Education, Kyung Hee University, Seoul 02447, Korea
| | - Kyuhyun Yoon
- Institute of Health and Environment, Seoul National University, Seoul 08826, Korea;
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Schantz SL, Eskenazi B, Buckley JP, Braun JM, Sprowles JN, Bennett DH, Cordero J, Frazier JA, Lewis J, Hertz-Picciotto I, Lyall K, Nozadi SS, Sagiv S, Stroustrup A, Volk HE, Watkins DJ. A framework for assessing the impact of chemical exposures on neurodevelopment in ECHO: Opportunities and challenges. ENVIRONMENTAL RESEARCH 2020; 188:109709. [PMID: 32526495 PMCID: PMC7483364 DOI: 10.1016/j.envres.2020.109709] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/22/2020] [Accepted: 05/19/2020] [Indexed: 05/30/2023]
Abstract
The Environmental influences on Child Health Outcomes (ECHO) Program is a research initiative funded by the National Institutes of Health that capitalizes on existing cohort studies to investigate the impact of early life environmental factors on child health and development from infancy through adolescence. In the initial stage of the program, extant data from 70 existing cohort studies are being uploaded to a database that will be publicly available to researchers. This new database will represent an unprecedented opportunity for researchers to combine data across existing cohorts to address associations between prenatal chemical exposures and child neurodevelopment. Data elements collected by ECHO cohorts were determined via a series of surveys administered by the ECHO Data Analysis Center. The most common chemical classes quantified in multiple cohorts include organophosphate pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, environmental phenols (including bisphenol A), phthalates, and metals. For each of these chemicals, at least four ECHO cohorts also collected behavioral data during infancy/early childhood using the Child Behavior Checklist. For these chemicals and this neurodevelopmental assessment (as an example), existing data from multiple ECHO cohorts could be pooled to address research questions requiring larger sample sizes than previously available. In addition to summarizing the data that will be available, the article also describes some of the challenges inherent in combining existing data across cohorts, as well as the gaps that could be filled by the additional data collection in the ECHO Program going forward.
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Affiliation(s)
- Susan L Schantz
- Department of Comparative Biosciences, College of Veterinary Medicine, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Brenda Eskenazi
- Center for Environmental Research and Children's Health, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
| | - Jessie P Buckley
- Department of Environmental Health and Engineering, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
| | - Joseph M Braun
- Department of Epidemiology, Brown University, Providence, RI, USA.
| | - Jenna N Sprowles
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Deborah H Bennett
- Department of Public Health Sciences, University of California, Davis, CA, USA.
| | - Jose Cordero
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA.
| | - Jean A Frazier
- Eunice Kennedy Shriver Center, Division of Child and Adolescent Psychiatry, University of Massachusetts Medical School, Worcester, MA, USA.
| | - Johnnye Lewis
- Community Environmental Health Program and Center for Native Environmental Health Equity Research, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.
| | | | - Kristen Lyall
- A.J. Drexel Autism Institute, Drexel University, Philadelphia, PA, USA.
| | - Sara S Nozadi
- Community Environmental Health Program and Center for Native Environmental Health Equity Research, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.
| | - Sharon Sagiv
- Center for Environmental Research and Children's Health, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
| | - AnneMarie Stroustrup
- Division of Newborn Medicine, Department of Pediatrics, Department of Environmental Medicine and Public Health, and Department of Obstetrics, Gynecology and Reproductive Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Heather E Volk
- Departments of Mental Health and Environmental Health and Engineering, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
| | - Deborah J Watkins
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA.
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Trentacosta CJ, Mulligan DJ. New directions in understanding the role of environmental contaminants in child development: Four themes. New Dir Child Adolesc Dev 2020; 2020:39-51. [PMID: 32920950 PMCID: PMC8189654 DOI: 10.1002/cad.20363] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Environmental contaminants, which include several heavy metals, persistent organic pollutants, and other harmful chemicals, impair several domains of child development. This article describes four themes from recent research on the impact of environmental contaminants on child development. The first theme, disparities in exposure, focuses on how marginalized communities are disproportionately exposed to harmful environmental contaminants. The second theme, complexity of exposures, encapsulates recent emphases on timing of exposures and mixtures of multiple exposures. The third theme, mechanisms that link exposures to outcomes, focuses on processes that elucidate how contaminants impact outcomes. The fourth theme, mitigating risks associated with exposures, sheds light on potential protective factors that could ameliorate many of the harmful effects of contaminant exposures. Developmental scientists are well positioned to contribute to interdisciplinary research that addresses these themes, which could foster additional conceptual and empirical innovations and inform policies and practices to mitigate risks and improve children's well-being.
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Sex-Dependent Effects of Developmental Lead Exposure in Wistar Rats: Evidence from Behavioral and Molecular Correlates. Int J Mol Sci 2020; 21:ijms21082664. [PMID: 32290408 PMCID: PMC7216048 DOI: 10.3390/ijms21082664] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/06/2020] [Accepted: 04/09/2020] [Indexed: 12/11/2022] Open
Abstract
Lead (Pb) exposure in early life affects brain development resulting in cognitive and behavioral deficits. Epidemiologic and experimental evidence of sex as an effect modifier of developmental Pb exposure is emerging. In the present study, we investigated Pb effects on behavior and mechanisms of neuroplasticity in the hippocampus and potential sex differences. To this aim, dams were exposed, from one month pre-mating to offspring weaning, to Pb via drinking water at 5 mg/kg body weight per day. In the offspring of both sexes, the longitudinal assessment of motor, emotional, and cognitive end points was performed. We also evaluated the expression and synaptic distribution of N-methyl-D-Aspartate receptor (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits at post-natal day (pnd) 23 and 70 in the hippocampus. Neonatal motor patterns and explorative behavior in offspring were affected in both sexes. Pb effects in emotional response and memory retention were observed in adult females only, preceded by increased levels of GluN2A and GluA1 subunits at the post-synapse at pnd 23. These data suggest that Pb exposure during development affects glutamatergic receptors distribution at the post-synaptic spine in females. These effects may contribute to alterations in selected behavioral domains.
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Desrochers-Couture M, Courtemanche Y, Forget-Dubois N, Bélanger RE, Boucher O, Ayotte P, Cordier S, Jacobson JL, Jacobson SW, Muckle G. Association between early lead exposure and externalizing behaviors in adolescence: A developmental cascade. ENVIRONMENTAL RESEARCH 2019; 178:108679. [PMID: 31454729 PMCID: PMC6759380 DOI: 10.1016/j.envres.2019.108679] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 07/12/2019] [Accepted: 08/16/2019] [Indexed: 05/23/2023]
Abstract
BACKGROUND Lead (Pb) exposure is associated with adverse neurological development. Most notably, it has been observed through externalizing behavior symptoms, as observed among Inuit children from northern Québec. Evidence for a persistent neurological impact of early Pb exposure later in life is however scarce. Pb exposure may initiate a developmental cascade that increases the risk of long-term behavior problems. OBJECTIVES Testing for direct associations between childhood Pb concentrations and adolescent externalizing symptoms and substance use, as well as indirect associations through childhood behavior assessments. METHODS The study sample is a longitudinal cohort of Inuit children (n = 212) followed since birth. Blood Pb concentrations were measured during childhood (median age = 11.4 years) and adolescence (median age = 18.5 years). Externalizing/inattentive behavior were teacher-assessed through the Teacher Report Form and the Disruptive Behavior Disorders Rating Scale for children. At the adolescence follow-up, behavior problems were self-reported by filling Achenbach's Youth Self-Report, the Barkley Adult ADHD-IV Rating Scale, and the Diagnostics Interview Schedule for Children. Adolescent substance use was also self-assessed through the DEP-ADO. Direct and indirect associations of child Pb concentrations with adolescent outcomes were tested through mediation models. RESULTS Child blood Pb concentrations were not directly associated with any adolescent outcomes. On the contrary, childhood Pb exposure was indirectly associated, through childhood externalizing behavior assessments, with adolescent externalizing behaviors, binge drinking, and cannabis use. These indirect associations held after controlling for adolescents' concurrent Pb blood concentrations. DISCUSSION Our results highlight the indirect but lasting effects of child Pb exposure on adolescent behavior problems, and the importance of childhood externalizing behavior in this relationship. Adverse early-life environment put children on a riskier developmental trajectory, increasing their likelihood of lifelong psychological, social and health problems.
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Affiliation(s)
| | - Yohann Courtemanche
- Centre de Recherche du CHU de Québec-Université Laval, Québec, Québec, Canada
| | | | - Richard E Bélanger
- Centre de Recherche du CHU de Québec-Université Laval, Québec, Québec, Canada; Département de Pédiatrie, Université Laval, Québec, Québec, Canada
| | - Olivier Boucher
- Département de Psychologie, Université de Montréal, Montréal, Québec, Canada; Service de Psychologie, Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada
| | - Pierre Ayotte
- Centre de Recherche du CHU de Québec-Université Laval, Québec, Québec, Canada; Centre de Toxicologie du Québec, Institut National de Santé Publique du Québec, Québec, Québec, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, Québec, Canada
| | - Sylvaine Cordier
- Centre de Recherche du CHU de Québec-Université Laval, Québec, Québec, Canada; Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail), UMR_S1085, F-35000 Rennes, France
| | - Joseph L Jacobson
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, USA
| | - Sandra W Jacobson
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, USA
| | - Gina Muckle
- Centre de Recherche du CHU de Québec-Université Laval, Québec, Québec, Canada; École de Psychologie, Université Laval, Québec, Québec, Canada.
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Dórea JG. Environmental exposure to low-level lead (Pb) co-occurring with other neurotoxicants in early life and neurodevelopment of children. ENVIRONMENTAL RESEARCH 2019; 177:108641. [PMID: 31421445 DOI: 10.1016/j.envres.2019.108641] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 08/08/2019] [Accepted: 08/08/2019] [Indexed: 06/10/2023]
Abstract
Lead (Pb) is a worldwide environmental contaminant that even at low levels influences brain development and affects neurobehavior later in life; nevertheless it is only a small fraction of the neurotoxicant (NT) exposome. Exposure to environmental Pb concurrent with other NT substances is often the norm, but their joint effects are challenging to study during early life. The aim of this review is to integrate studies of Pb-containing NT mixtures during the early life and neurodevelopment outcomes of children. The Pb-containing NT mixtures that have been most studied involve other metals (Mn, Al, Hg, Cd), metalloids (As), halogen (F), and organo-halogen pollutants. Co-occurring Pb-associated exposures during pregnancy and lactation depend on the environmental sources and the metabolism and half-life of the specific NT contaminant; but offspring neurobehavioral outcomes are also influenced by social stressors. Nevertheless, Pb-associated effects from prenatal exposure portend a continued burden on measurable neurodevelopment; they thus favor increased neurological health issues, decrements in neurobehavioral tests and reductions in the quality of life. Neurobehavioral test outcomes measured in the first 1000 days showed Pb-associated negative outcomes were frequently noticed in infants (<6 months). In older (preschool and school) children studies showed more variations in NT mixtures, children's age, and sensitivity and/or specificity of neurobehavioral tests; these variations and choice of statistical model (individual NT stressor or collective effect of mixture) may explain inconsistencies. Multiple exposures to NT mixtures in children diagnosed with 'autism spectrum disorders' (ASD) and 'attention deficit and hyperactivity disorders' (ADHD), strongly suggest a Pb-associated effect. Mixture potency (number or associated NT components and respective concentrations) and time (duration and developmental stage) of exposure often showed a measurable impact on neurodevelopment; however, net effects, reversibility and/or predictability of delays are insufficiently studied and need urgent attention. Nevertheless, neurodevelopment delays can be prevented and/or attenuated if public health policies are implemented to protect the unborn and the young child.
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Affiliation(s)
- José G Dórea
- Universidade de Brasília, Brasília, 70919-970, DF, Brazil.
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Rude KM, Pusceddu MM, Keogh CE, Sladek JA, Rabasa G, Miller EN, Sethi S, Keil KP, Pessah IN, Lein PJ, Gareau MG. Developmental exposure to polychlorinated biphenyls (PCBs) in the maternal diet causes host-microbe defects in weanling offspring mice. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 253:708-721. [PMID: 31336350 PMCID: PMC6719698 DOI: 10.1016/j.envpol.2019.07.066] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 07/12/2019] [Accepted: 07/12/2019] [Indexed: 05/05/2023]
Abstract
The gut microbiota is important for maintaining homeostasis of the host. Gut microbes represent the initial site for toxicant processing following dietary exposures to environmental contaminants. The diet is the primary route of exposure to polychlorinated biphenyls (PCBs), which are absorbed via the gut, and subsequently interfere with neurodevelopment and behavior. Developmental exposures to PCBs have been linked to increased risk of neurodevelopmental disorders (NDD), including autism spectrum disorder (ASD), which are also associated with a high prevalence of gastrointestinal (GI) distress and intestinal dysbiosis. We hypothesized that developmental PCB exposure impacts colonization of the gut microbiota, resulting in GI pathophysiology, in a genetically susceptible host. Mouse dams expressing two heritable human mutations (double mutants [DM]) that result in abnormal Ca2+ dynamics and produce behavioral deficits (gain of function mutation in the ryanodine receptor 1 [T4826I-RYR1] and a human CGG repeat expansion [170-200 CGG repeats] in the fragile X mental retardation gene 1 [FMR1 premutation]). DM and congenic wild type (WT) controls were exposed to PCBs (0-6 mg/kg/d) in the diet starting 2 weeks before gestation and continuing through postnatal day 21 (P21). Intestinal physiology (Ussing chambers), inflammation (qPCR) and gut microbiome (16S sequencing) studies were performed in offspring mice (P28-P30). Developmental exposure to PCBs in the maternal diet caused significant mucosal barrier defects in ileum and colon (increased secretory state and tight junction permeability) of juvenile DM mice. Furthermore, PCB exposure increased the intestinal inflammatory profile (Il6, Il1β, and Il22), and resulted in dysbiosis of the gut microbiota, including altered β-diversity, in juvenile DM mice developmentally exposed to 1 mg/kg/d PCBs when compared to WT controls. Collectively, these findings demonstrate a novel interaction between PCB exposure and the gut microbiota in a genetically susceptible host that provide novel insight into environmental risk factors for neurodevelopmental disorders.
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Affiliation(s)
- Kavi M Rude
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Matteo M Pusceddu
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Ciara E Keogh
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Jessica A Sladek
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Gonzalo Rabasa
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Elaine N Miller
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Sunjay Sethi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Kimberly P Keil
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Pamela J Lein
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
| | - Mélanie G Gareau
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States.
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Cai H, Xu X, Zhang Y, Cong X, Lu X, Huo X. Elevated lead levels from e-waste exposure are linked to sensory integration difficulties in preschool children. Neurotoxicology 2019; 71:150-158. [PMID: 30664973 DOI: 10.1016/j.neuro.2019.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 12/22/2018] [Accepted: 01/16/2019] [Indexed: 02/05/2023]
Abstract
Exposure to lead is associated with adverse effects on neurodevelopment. However, studies of the effects of lead on sensory integration are few. The purpose of this research is to investigate the effect of lead exposure on child sensory integration by correlating the blood lead levels of children with sensory processing measures. A total of 574 children, from 3 to 6 years of age, 358 from an electronic waste (e-waste) recycling town named Guiyu, and 216 from Haojiang, a nearby town with no e-waste recycling activity, were recruited in this study. The median blood lead level in Guiyu children was 4.88 μg/dL, higher than the 3.47 μg/dL blood lead level in Haojiang children (P < 0.001). 47.2% of Guiyu children had blood lead levels exceeding 5 μg/dL. The median concentration of serum cortisol, an HPA-axis biomarker, in Guiyu children was significantly lower than in Haojiang, and was negatively correlated with blood lead levels. All subscale scores and the total score of the Sensory Processing Measure (Hong Kong Chinese version, SPM-HKC) in Guiyu children were higher than Haojiang children, indicating greater difficulties, especially for touch, body awareness, balance and motion, and total sensory systems. Sensory processing scores were positively correlated with blood lead, except for touch, which was negatively correlated with serum cortisol levels. Simultaneously, all subscale scores and the total SPM-HKC scores for children with high blood lead levels (blood lead > 5 μg/dL) were higher than those in the low blood lead level group (blood lead < 5 μg/dL), especially for hearing, touch, body awareness, balance and motion, and total sensory systems. Our findings suggest that lead exposure in e-waste recycling areas may result in a decrease in serum cortisol levels and an increase in child sensory integration difficulties. Cortisol may be involved in touch-related sensory integration difficulties.
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Affiliation(s)
- Haoxing Cai
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Xijin Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou 515041, Guangdong, China; Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Yu Zhang
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou 515041, Guangdong, China; Immunoendocrinology, Division of Medical Biology, Department of Pathology and Medical Biology, University of Groningen and University Medical Center Groningen (UMCG), Hanzeplein 1, 9713 GZ Groningen, the Netherlands
| | - Xiaowei Cong
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Xueling Lu
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou 515041, Guangdong, China; Department of Epidemiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, the Netherlands
| | - Xia Huo
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, 855 East Xingye Avenue, Guangzhou 511486, Guangdong, China.
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Jaffee SR. Lead exposure and child maltreatment as models for how to conceptualize early-in-life risk factors for violence. Infant Ment Health J 2019; 40:23-38. [DOI: 10.1002/imhj.21756] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Association of Low Lead Levels with Behavioral Problems and Executive Function Deficits in Schoolers from Montevideo, Uruguay. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15122735. [PMID: 30518085 PMCID: PMC6313712 DOI: 10.3390/ijerph15122735] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 11/27/2018] [Accepted: 11/29/2018] [Indexed: 01/11/2023]
Abstract
The negative effect of lead exposure on children's intelligence is well-documented. Less is known about the impact of lead on the use of executive functions to self-regulate behavior. We measured blood lead level (BLL) in a sample of first grade children from Montevideo, Uruguay (n = 206, age 6.7 ± 0.5 years, 59.7% boys). Behavior was assessed with teacher versions of the Conners Rating Scale (CRS) and the Behavior Rating Inventory of Executive Functions (BRIEF). Mean BLL was 4.2 ± 2.1 μg/dL; 10% had mild-to-severe ratings of Attentional Deficit with Hyperactivity Disorder (ADHD) (T score > 65). In negative binomial regression, BLL was not associated with CRS sub-scales, but was associated with a poorer ability to inhibit inappropriate behaviors, prevalence ratio (PR) [95% CI]: 1.01 [1.00, 1.03] as measured by the BRIEF. In covariate-adjusted models, the association with BLL was attenuated. When stratified by sex, the covariate-adjusted association between BLL, hyperactivity, poorer inhitibion, emotional control, and behavioral regulation was marginally significant for girls but not boys. In summary, among children with low lead-exposure, we found some, but nonetheless modest, evidence of a relationship between higher BLL and child behavior. If confirmed by larger studies and other objective measures of behavior, such links could have implications for learning and social interaction, particularly among girls.
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Dórea JG. Multiple low-level exposures: Hg interactions with co-occurring neurotoxic substances in early life. Biochim Biophys Acta Gen Subj 2018; 1863:129243. [PMID: 30385391 DOI: 10.1016/j.bbagen.2018.10.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/01/2018] [Accepted: 10/19/2018] [Indexed: 12/11/2022]
Abstract
All chemical forms of Hg can affect neurodevelopment; however, low levels of organic Hg (methylmercury-MeHg and ethylmercury-EtHg in Thimerosal-containing vaccines, hereafter 'TCV') exposures during early life (pregnancy and lactation) co-occur with other environmental neurotoxic substances. These neurotoxicants may act in parallel, synergistically, or antagonistically to Hg. Nevertheless, the risks of neurotoxicity associated with multiple neuro-toxicants depend on type, time, combinations of exposure, and environmental and/or genetic-associated factors. Neurological developmental disorders, delays in cognition and behavioral outcomes associated with multiple exposures (which include Hg) may show transient or lasting outcomes depending on constitutional and/or environmental factors that can interact to neutralize, aggravate or attenuate these effects; often these studies are challenging to interpret. During pregnancy and lactation, fish-MeHg exposure is frequently confounded with the opposing effects of neuroactive nutrients (in fish) that lead to positive, negative, or no effects on neurobehavioral tests. In infancy, exposures to acute binary mixtures (TCV- EtHg and Al-adjuvants in infant immunizations) are associated with increased risks of tics and other developmental disorders. Despite the certitude that promulgates single environmental neurotoxicants, empirical comparisons of combined exposures indicate that Hg-related outcome is uneven. Hg in combination with other neurotoxic mixtures may elevate risks of neurotoxicity, but these risks arise in circumstances that are not yet predictable. Therefore, to achieve the goals of the Minamata treaty and to safeguard the health of children, low levels of mercury exposure (in any chemical form) needs to be further reduced whether the source is environmental (air- and food-borne) or iatrogenic (pediatric TCVs).
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Affiliation(s)
- José G Dórea
- Universidade de Brasília, Brasília 70919-970, DF, Brazil..
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Polanska K, Hanke W, Pawlas N, Wesolowska E, Jankowska A, Jagodic M, Mazej D, Dominowska J, Grzesiak M, Mirabella F, Chiarotti F, Calamandrei G. Sex-Dependent Impact of Low-Level Lead Exposure during Prenatal Period on Child Psychomotor Functions. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15102263. [PMID: 30332762 PMCID: PMC6210236 DOI: 10.3390/ijerph15102263] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/09/2018] [Accepted: 10/12/2018] [Indexed: 12/18/2022]
Abstract
The impact of exposure to lead on child neurodevelopment has been well established. However, sex differences in vulnerability are still not fully explained. We aimed at evaluating the effect of a low-level lead exposure, as measured between 20 to 24 weeks of pregnancy and in cord blood, on developmental scores up to 24 months of age in 402 children from the Polish Mother and Child Cohort (REPRO_PL). Additionally, sex-dependent susceptibility to lead at this very early stage of psychomotor development was assessed. The blood lead levels were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). In order to estimate the children’s neurodevelopment, the Bayley Scales of Infant and Toddler Development was applied. The geometric mean (GM) for blood lead level during 20–24 weeks of pregnancy was 0.99 ± 0.15 µg/dL and, in the cord blood, it was 0.96 ± 0.16 µg/dL. There was no statistically significant impact of lead exposure during prenatal period on the girls’ psychomotor abilities. Among the boys, we observed lower scores for cognitive functions, along with increasing cord blood lead levels (β = −2.07; p = 0.04), whereas the results for the language and motor abilities were not statistically significant (p > 0.05). Our findings show that fetal exposure to very low lead levels might affect early cognitive domain, with boys being more susceptible than girls. Education on health, higher public awareness, as well as intervention programs, along with relevant regulations, are still needed to reduce risks for the vulnerable population subgroups.
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Affiliation(s)
- Kinga Polanska
- Department of Environmental Epidemiology, Nofer Institute of Occupational Medicine, 91-348 Lodz, Poland.
| | - Wojciech Hanke
- Department of Environmental Epidemiology, Nofer Institute of Occupational Medicine, 91-348 Lodz, Poland.
| | - Natalia Pawlas
- Chair and Department of Pharmacology, Medical University of Silesia, School of Medicine with Division of Dentistry in Zabrze, 41 808 Zabrze, Poland.
| | - Ewelina Wesolowska
- Department of Environmental Epidemiology, Nofer Institute of Occupational Medicine, 91-348 Lodz, Poland.
| | - Agnieszka Jankowska
- Department of Environmental Epidemiology, Nofer Institute of Occupational Medicine, 91-348 Lodz, Poland.
| | - Marta Jagodic
- Department of Environmental Sciences, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia.
| | - Darja Mazej
- Department of Environmental Sciences, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia.
| | - Jolanta Dominowska
- Department of Teaching Midwifery, Medical University of Lodz, 90-419 Lodz, Poland.
| | - Mariusz Grzesiak
- Obstetrics, Perinatology and Gynecology Department, Polish Mother's Memorial Hospital Research Institute, 93-338 Lodz, Poland.
| | - Fiorino Mirabella
- Center for Behavioral Sciences and Mental Health, National Institute of Health, I-00161 Rome, Italy.
| | - Flavia Chiarotti
- Center for Behavioral Sciences and Mental Health, National Institute of Health, I-00161 Rome, Italy.
| | - Gemma Calamandrei
- Center for Behavioral Sciences and Mental Health, National Institute of Health, I-00161 Rome, Italy.
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The Neurodevelopmental Toxicity of Lead: History, Epidemiology, and Public Health Implications. LINKING ENVIRONMENTAL EXPOSURE TO NEURODEVELOPMENTAL DISORDERS 2018. [DOI: 10.1016/bs.ant.2018.03.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Wang P, Tuvblad C, Younan D, Franklin M, Lurmann F, Wu J, Baker LA, Chen JC. Socioeconomic disparities and sexual dimorphism in neurotoxic effects of ambient fine particles on youth IQ: A longitudinal analysis. PLoS One 2017; 12:e0188731. [PMID: 29206872 PMCID: PMC5716576 DOI: 10.1371/journal.pone.0188731] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 11/13/2017] [Indexed: 12/27/2022] Open
Abstract
Mounting evidence indicates that early-life exposure to particulate air pollutants pose threats to children's cognitive development, but studies about the neurotoxic effects associated with exposures during adolescence remain unclear. We examined whether exposure to ambient fine particles (PM2.5) at residential locations affects intelligence quotient (IQ) during pre-/early- adolescence (ages 9-11) and emerging adulthood (ages 18-20) in a demographically-diverse population (N = 1,360) residing in Southern California. Increased ambient PM2.5 levels were associated with decreased IQ scores. This association was more evident for Performance IQ (PIQ), but less for Verbal IQ, assessed by the Wechsler Abbreviated Scale of Intelligence. For each inter-quartile (7.73 μg/m3) increase in one-year PM2.5 preceding each assessment, the average PIQ score decreased by 3.08 points (95% confidence interval = [-6.04, -0.12]) accounting for within-family/within-individual correlations, demographic characteristics, family socioeconomic status (SES), parents' cognitive abilities, neighborhood characteristics, and other spatial confounders. The adverse effect was 150% greater in low SES families and 89% stronger in males, compared to their counterparts. Better understanding of the social disparities and sexual dimorphism in the adverse PM2.5-IQ effects may help elucidate the underlying mechanisms and shed light on prevention strategies.
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Affiliation(s)
- Pan Wang
- Center for Health Policy Research, University of California Los Angeles, Los Angeles, United States of America
| | - Catherine Tuvblad
- Department of Psychology, University of Southern California, Los Angeles, United States of America
- School of Law, Psychology and Social Work, Örebro University, Örebro, Sweden
| | - Diana Younan
- Department of Preventive Medicine, University of Southern California, Los Angeles, United States of America
| | - Meredith Franklin
- Department of Preventive Medicine, University of Southern California, Los Angeles, United States of America
| | - Fred Lurmann
- Sonoma Technology, Inc., Petaluma, California, United States of America
| | - Jun Wu
- Program in Public Health, University of California Irvine, Irvine, United States of America
| | - Laura A. Baker
- Department of Psychology, University of Southern California, Los Angeles, United States of America
| | - Jiu-Chiuan Chen
- Department of Preventive Medicine, University of Southern California, Los Angeles, United States of America
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Jensen SKG, Berens AE, Nelson CA. Effects of poverty on interacting biological systems underlying child development. THE LANCET CHILD & ADOLESCENT HEALTH 2017; 1:225-239. [DOI: 10.1016/s2352-4642(17)30024-x] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 06/14/2017] [Accepted: 06/19/2017] [Indexed: 12/26/2022]
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Grant KS, Petroff R, Isoherranen N, Stella N, Burbacher TM. Cannabis use during pregnancy: Pharmacokinetics and effects on child development. Pharmacol Ther 2017; 182:133-151. [PMID: 28847562 DOI: 10.1016/j.pharmthera.2017.08.014] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The broad-based legalization of cannabis use has created a strong need to understand its impact on human health and behavior. The risks that may be associated with cannabis use, particularly for sensitive subgroups such as pregnant women, are difficult to define because of a paucity of dose-response data and the recent increase in cannabis potency. Although there is a large body of evidence detailing the mode of action of Δ9-tetrahydrocannabinol (THC) in adults, little work has focused on understanding how cannabis use during pregnancy may impact the development of the fetal nervous system and whether additional plant-derived cannabinoids might participate. This manuscript presents an overview of the historical and contemporary literature focused on the mode of action of THC in the developing brain, comparative pharmacokinetics in both pregnant and nonpregnant model systems and neurodevelopmental outcomes in exposed offspring. Despite growing public health significance, pharmacokinetic studies of THC have focused on nonpregnant adult subjects and there are few published reports on disposition parameters during pregnancy. Data from preclinical species show that THC readily crosses the placenta although fetal exposures appear lower than maternal exposures. The neurodevelopmental data in humans and animals suggest that prenatal exposure to THC may lead to subtle, persistent changes in targeted aspects of higher-level cognition and psychological well-being. There is an urgent need for well-controlled studies in humans and preclinical models on THC as a developmental neurotoxicant. Until more information is available, pregnant women should not assume that using cannabis during pregnancy is safe.
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Affiliation(s)
- Kimberly S Grant
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA; Center on Human Development and Disability, University of Washington, Seattle, WA, USA; Washington National Primate Research Center, University of Washington, Seattle, WA, USA.
| | - Rebekah Petroff
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
| | - Nina Isoherranen
- Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Nephi Stella
- Department of Pharmacology, School of Medicine, University of Washington, Seattle, WA, USA; Department of Psychiatry and Behavioral Sciences, School of Medicine, University of Washington, Seattle, WA, USA
| | - Thomas M Burbacher
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA; Center on Human Development and Disability, University of Washington, Seattle, WA, USA; Washington National Primate Research Center, University of Washington, Seattle, WA, USA
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Prenatal environmental chemical exposures and longitudinal patterns of child neurobehavior. Neurotoxicology 2017; 62:192-199. [PMID: 28736150 DOI: 10.1016/j.neuro.2017.07.027] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/21/2017] [Accepted: 07/17/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Prenatal chemical exposures may adversely affect neurodevelopment, but few studies have examined the persistence of these associations. We examined whether associations between prenatal bisphenol A (BPA) or polybrominated diphenyl ether (PBDE) exposures persist or resolve as children age. METHODS We followed 346 mother-child pairs (enrolled 2003-2006) from Cincinnati, OH from pregnancy until children were 8 years old. We measured BPA in urine collected at 16 and 26 weeks gestation and PBDE-47 in serum collected at 16 weeks gestation. We administered repeated measures of children's behavior, mental/psychomotor development, and IQ from ages 1-8 years. We determined if associations of BPA or PBDE-47 with child neurobehavior persisted or resolved as children aged using linear mixed models and estimated neurobehavioral measure reproducibility using intraclass correlation coefficients (ICCs). RESULTS Higher BPA in girls and higher PBDE-47 in both boys and girls were associated with more externalizing behaviors; these associations persisted from ages 2-8 years (exposure×age interaction p-values≥0.36). Higher PBDE-47 concentrations were associated with decreases in MDI from ages 1-3 years (PBDE-47x age interaction p-value=0.03) and persistently lower IQ at ages 5 and 8 years (PBDE-47×age interaction p-value=0.56). Mental/psychomotor abilities had fair reproducibility from ages 1-3 years (ICCs∼0.4), cognitive abilities from ages 5 to 8 years had excellent reproducibility (ICCs=0.7-0.8), and parent-reported behaviors from ages 2-8 years had poor to good reproducibility (ICCs=0.38-0.59). CONCLUSIONS Prenatal BPA and PBDE-47 concentrations were persistently associated with more externalizing behaviors. PBDE-47 concentrations were inversely associated with cognitive abilities that strengthened over time.
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Taylor CM, Kordas K, Golding J, Emond AM. Effects of low-level prenatal lead exposure on child IQ at 4 and 8 years in a UK birth cohort study. Neurotoxicology 2017; 62:162-169. [PMID: 28687448 PMCID: PMC5630203 DOI: 10.1016/j.neuro.2017.07.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/28/2017] [Accepted: 07/03/2017] [Indexed: 11/09/2022]
Abstract
The association between prenatal exposure to lead and deficits in offspring cognitive function is not well established. Our aim was to evaluate the association between prenatal lead exposure and child IQ at age 4 and 8 years in an observational birth cohort study. There was no association of prenatal lead exposure with child IQ at either 4 or 8 years old. There was a suggestion, however, that boys are more susceptible than girls to prenatal exposure to lead.
Background The association between childhood exposure to lead (Pb) and deficits in cognitive function is well established. The association with prenatal exposure, however, is not well understood, even though the potential adverse effects are equally important. Objectives To evaluate the association between low prenatal exposure to lead and IQ in children, to determine whether there were sex differences in the associations, and to evaluate the moderation effect of prenatal Pb exposure on child IQ. Methods Whole blood samples from pregnant women enrolled in ALSPAC (n = 4285) and from offspring at age 30 months (n = 235) were analysed for Pb. Associations between prenatal blood lead concentrations (B-Pb) and child IQ at age 4 and 8 years (WPPSI and WISC-III, respectively) were examined in adjusted regression models. Results There was no association of prenatal lead exposure with child IQ at 4 or 8 years old in adjusted regression models, and no moderation of the association between child B-Pb and IQ. However, there was a positive association for IQ at age 8 years in girls with a predicted increase in IQ (points) per 1 μg/dl of: verbal 0.71, performance 0.57, total 0.73. In boys, the coefficients tended to be negative (−0.15, −0.42 and −0.29 points, respectively). Conclusion Prenatal lead exposure was not associated with adverse effects on child IQ at age 4 or 8 years in this study. There was, however, some evidence to suggest that boys are more susceptible than girls to prenatal exposure to lead. Further investigation in other cohorts is required.
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Affiliation(s)
- Caroline M Taylor
- Centre for Child and Adolescent Health, School of Social and Community Medicine, University of Bristol, UK.
| | - Katarzyna Kordas
- Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo, Buffalo, NY, USA
| | - Jean Golding
- Centre for Child and Adolescent Health, School of Social and Community Medicine, University of Bristol, UK
| | - Alan M Emond
- Centre for Child and Adolescent Health, School of Social and Community Medicine, University of Bristol, UK
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LaKind JS, Anthony LG, Goodman M. Review of reviews on exposures to synthetic organic chemicals and children's neurodevelopment: Methodological and interpretation challenges. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2017; 20:390-422. [PMID: 28952888 DOI: 10.1080/10937404.2017.1370847] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Environmental epidemiology data are becoming increasingly important in public health decision making, which commonly incorporates a systematic review of multiple studies. This review addresses two fundamental questions: What is the quality of available reviews on associations between exposure to synthetic organic chemicals and neurodevelopmental outcomes? What is the value (e.g., quality and consistency) of the underlying literature? Published reviews on associations between synthetic organic environmental chemical exposures and neurodevelopmental outcomes in children were systematically evaluated. Seventy-four relevant reviews were identified, and these were evaluated with respect to four methodological characteristics: (1) systematic inclusion/exclusion criteria and reproducible methods for search and retrieval of studies; (2) structured evaluation of underlying data quality; (3) systematic assessment of consistency across specific exposure-outcome associations; and (4) evaluation of reporting/publication bias. None of the 74 reviews fully met the criteria for all four methodological characteristics. Only four reviews met two criteria, and six reviews fulfilled only one criterion. Perhaps more importantly, the higher quality reviews were not able to meet all of the criteria owing to the shortcomings of underlying studies, which lacked comparability in terms of specific research question of interest, overall design, exposure assessment, outcome ascertainment, and analytic methods. Thus, even the most thoughtful and rigorous review may be of limited value if the underlying literature includes investigations that address different hypotheses and are beset by methodological inconsistencies and limitations. Issues identified in this review of reviews illustrate considerable challenges that are facing assessments of epidemiological evidence.
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Affiliation(s)
- Judy S LaKind
- a LaKind Associates , LLC , Catonsville , MD 21228 , USA
- b Department of Epidemiology and Public Health , University of Maryland School of Medicine , Baltimore , MD 21201 , USA
| | - Laura G Anthony
- c Center for Autism Spectrum Disorders, Children's National Health System , The George Washington University Medical Center , 15245 Shady Grove Road, Suite 350, Rockville , MD 20850 USA
| | - Michael Goodman
- d Department of Epidemiology, Rollins School of Public Health , Emory University , 1518 Clifton Rd, Atlanta , GA 30322 USA
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