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Costet N, Doyen M, Rouget F, Michineau L, Monfort C, Cirtiu CM, Kadhel P, Multigner L, Pladys P, Cordier S. Early exposure to mercury and cardiovascular function of seven-year old children in Guadeloupe (French West Indies). ENVIRONMENTAL RESEARCH 2024; 246:117955. [PMID: 38159660 DOI: 10.1016/j.envres.2023.117955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/02/2023] [Accepted: 12/13/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND The cardiotoxicity of prenatal exposure to mercury has been suggested in populations having regular contaminated seafood intake, though replications in the literature are inconsistent. METHODS The Timoun Mother-Child Cohort Study was set up in Guadeloupe, an island in the Caribbean Sea where seafood consumption is regular. At seven years of age, 592 children underwent a medical examination, including cardiac function assessment. Blood pressure (BP) was taken using an automated blood pressure monitor, heart rate variability (HRV, 9 parameters) and electrocardiogram (ECG) characteristics (QT, T-wave parameters) were measured using Holter cardiac monitoring during the examination. Total mercury concentrations were measured in cord blood at birth (median = 6.6 μg/L, N = 399) and in the children's blood at age 7 (median = 1.7 μg/L, N = 310). Adjusted linear and non-linear modelling was used to study the association of each cardiac parameter with prenatal and childhood exposures. Sensitivity analyses included co-exposures to lead and cadmium, adjustment for maternal seafood consumption, selenium and polyunsaturated fatty acids (n3-PUFAs), and for sporting activity. RESULTS Higher prenatal mercury was associated with higher systolic BP at 7 years of age (βlog2 = 1.02; 95% Confidence Interval (CI) = 0.10, 1.19). In boys, intermediate prenatal exposure was associated with reduced overall HRV and parasympathetic activity, and longer QT was observed with increasing prenatal mercury (βlog2 = 4.02; CI = 0.48, 7.56). In girls, HRV tended to increase linearly with prenatal exposure, and no association was observed with QT-wave related parameters. Mercury exposure at 7 years was associated with decreased BP in girls (βlog2 = -1.13; CI = -2.22, -0.004 for diastolic BP). In boys, the low/high-frequency (LF/HF) ratio increased for intermediate levels of exposure. CONCLUSION Our study suggests sex-specific and non-monotonic modifications in some cardiac health parameters following prenatal exposure to mercury in pre-pubertal children from an insular fish-consuming population.
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Affiliation(s)
- Nathalie Costet
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) -UMR_S 1085, Rennes, France.
| | - Matthieu Doyen
- Univ Rennes, Inserm, LTSI - UMR 1099, Rennes, France; IADI, U1254, Inserm and Université de Lorraine, Nancy, France.
| | - Florence Rouget
- Univ Rennes, CHU de Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, Rennes, France.
| | - Leah Michineau
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) -UMR_S 1085, Pointe à Pitre, France.
| | - Christine Monfort
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) -UMR_S 1085, Rennes, France.
| | - Ciprian-Mihai Cirtiu
- Centre de Toxicologie Du Québec, Institut National de Santé Publique Du Québec, Québec, Québec, Canada.
| | - Philippe Kadhel
- CHU de Guadeloupe, Univ Antilles, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, Pointe à Pitre, France.
| | - Luc Multigner
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) -UMR_S 1085, Rennes, France.
| | - Patrick Pladys
- Univ Rennes, CHU de Rennes, Inserm, LTSI - UMR 1099, Rennes, France.
| | - Sylvaine Cordier
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) -UMR_S 1085, Rennes, France.
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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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Chan PHY, Kwok KM, Chan MHM, Li AM, Chan IHS, Fok TF, Lam HS. Prenatal methylmercury exposure is associated with decrease heart rate variability in children. ENVIRONMENTAL RESEARCH 2021; 200:111744. [PMID: 34310966 DOI: 10.1016/j.envres.2021.111744] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 07/19/2021] [Accepted: 07/19/2021] [Indexed: 05/10/2023]
Abstract
BACKGROUND Although several epidemiological studies have suggested mercury (Hg) might be associated with cardiotoxicity, the impact of Hg exposure on cardiac autonomic activity and blood pressure in children has not been investigated at Hg exposure levels equivalent to the Environmental Protection Agency (EPA) reference dose. OBJECTIVE To investigate the association between low dose prenatal and recent methylmercury (MeHg) exposures and cardiac autonomic function and blood pressure with adjustment for factors such as fish consumption among children from a high fish consumption coastal city. METHODS Children aged 7-8 years were recruited from the birth cohort of our previous study. Heart rate variability (HRV), resting heart rate (RHR) and blood pressure were measured as surrogate markers of cardiac autonomic function. Cord blood and current whole blood Hg concentration were used as biomarkers of prenatal and recent MeHg exposure, respectively. Recent fish consumption information was estimated with a food frequency questionnaire. RESULTS Among 604 children, median cord blood and whole blood Hg concentrations were 45.9 nmol/L (IQR: 32.8-65.03 nmol/L) and 13.57 nmol/L (IQR: 9.29-19.72 nmol/L), respectively. Our results demonstrated that prenatal MeHg exposure was associated with decreased HRV (i.e. low CVRR, SDRR, and RMSSD), reflecting reduced parasympathetic activity (i.e. low CCVHF and HF), and a sympathovagal balance shift toward sympathetic predominance (i.e. high %LF and LF/HF ratio). Adjustment of recent fish consumption further increased the significance and magnitude of the adverse associations of MeHg. CONCLUSION The results of this study suggest that prenatal MeHg exposure is associated with decreased parasympathetic modulation of cardiac autonomic function in children.
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Affiliation(s)
- Peggy Hiu Ying Chan
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong; Brain and Mind Institute, The Chinese University of Hong Kong, Hong Kong
| | - Ka Ming Kwok
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Michael Ho Ming Chan
- Department of Chemical Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Albert Martin Li
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Iris Hiu Shuen Chan
- Department of Chemical Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Tai Fai Fok
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Hugh Simon Lam
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.
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4
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Pal A, Martinez F, Aguila AP, Akey MA, Chatterjee R, Conserman MGE, Aysola RS, Henderson LA, Macey PM. Beat-to-beat blood pressure variability in patients with obstructive sleep apnea. J Clin Sleep Med 2021; 17:381-392. [PMID: 33089774 DOI: 10.5664/jcsm.8866] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
STUDY OBJECTIVES Cardiovascular comorbidities in obstructive sleep apnea (OSA) are difficult to treat, perhaps due to autonomic dysfunction. We assessed beat-to-beat blood pressure (BP) variability (BPV) in OSA while considering other markers derived from electrocardiogram and continuous BP signals. METHODS We studied 66 participants (33 participants with OSA: respiratory event index [mean ± SEM]: 21.1 ± 2.7 events/h; 12 females, aged 51.5 ± 2.4 years; body mass index: 32.8 ± 1.4 kg/m²; 33 healthy controls: 20 females; aged 45.3 ± 2.4 years; body mass index: 26.3 ± 0.7 kg/m²). We collected 5-minute resting noninvasive beat-to-beat BP and electrocardiogram values. From BP, we derived systolic, diastolic, and mean BP values, and calculated variability as standard deviations (systolic BPV, diastolic BPV, BPV). We also calculated diastole-to-systole time (time to peak). From the electrocardiogram, we derived QRS markers and calculated heart rate and heart rate variability. We performed a multivariate analysis of variance based on sex and group (OSA vs control), with Bonferroni-corrected post hoc comparisons (P ≤ .05) between groups. We calculated correlations of BPV with biological variables. RESULTS Multivariate analysis of variance showed effects of diastolic BPV and BPV in OSA; post hoc comparisons revealed high diastolic BPV and BPV only in female participants with OSA vs controls. QRS duration was higher in OSA, with post hoc comparisons showing the effect only in males. BPV correlated positively with heart rate variability in controls but not in participants with OSA. BPV correlated positively with time to peak in females with OSA and OSA combined, whereas there was no BPV-time-to-peak correlation in healthy participants. CONCLUSIONS The findings show sex-specific autonomic dysfunction reflected in beat-to-beat BP in OSA. The higher BPV may reflect poor baroreflex control or vascular damage in OSA, which are potential precursors to cardiovascular complications.
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Affiliation(s)
- Amrita Pal
- UCLA School of Nursing, Los Angeles, California
| | | | | | | | | | | | - Ravi S Aysola
- Division of Pulmonary and Critical Care, David Geffen School of Medicine at UCLA, University of California, Los Angeles, California
| | - Luke A Henderson
- Department of Anatomy and Histology, Sydney Medical School, University of Sydney, Sydney, Australia
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Davidson PW, van Wijngaarden E, Shamlaye C, Strain JJ, Myers GJ. Putting findings from the Seychelles Child Development Study into perspective: The importance of a historical special issue of the Seychelles Medical and Dental Journal. Neurotoxicology 2020; 76:111-113. [PMID: 31706981 PMCID: PMC6980718 DOI: 10.1016/j.neuro.2019.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 10/25/2019] [Indexed: 11/20/2022]
Abstract
We are pleased to introduce this special issue of Neurotoxicology. It reproduces Volume 7, Number 1 of the Seychelles Medical and Dental Journal (SMDJ), initially published in November 2004. Publication of the SMDJ was discontinued in 2005 and the manuscripts it published are no longer accessible to the scientific community. The papers in this special issue lay the background for the Seychelles Child Development Study (SCDS) and provide valuable data on the MeHg exposures that occurred at Niigata, Japan. They are relevant to the ongoing debate over whether the consumption of fish and consequently low-level exposure to methylmercury (MeHg) is a risk to human health.
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Affiliation(s)
- P W Davidson
- University of Rochester School of Medicine and Dentistry, United States
| | - E van Wijngaarden
- University of Rochester School of Medicine and Dentistry, United States.
| | - C Shamlaye
- University of Rochester School of Medicine and Dentistry, United States
| | - J J Strain
- University of Rochester School of Medicine and Dentistry, United States
| | - G J Myers
- University of Rochester School of Medicine and Dentistry, United States
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6
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Zareba W, Thurston SW, Zareba G, Couderc JP, Evans K, Xia J, Watson GE, Strain JJ, McSorley E, Yeates A, Mulhern M, Shamlaye CF, Bovet P, van Wijngaarden E, Davidson PW, Myers GJ. Prenatal and recent methylmercury exposure and heart rate variability in young adults: the Seychelles Child Development Study. Neurotoxicol Teratol 2019; 74:106810. [PMID: 31128243 DOI: 10.1016/j.ntt.2019.106810] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 03/22/2019] [Accepted: 05/21/2019] [Indexed: 12/19/2022]
Abstract
Epidemiologic evidence of an adverse association between exposure to methylmercury (MeHg) from consuming fish and heart rate variability (HRV) is inconclusive. We aimed to evaluate MeHg exposure in relation to HRV parameters in a large cohort of young adults from a high fish consuming population in the Republic of Seychelles. Main Cohort participants in the Seychelles Child Development Study were evaluated at a mean age of 19 years. Prenatal MeHg exposure was determined in maternal hair growing during pregnancy and recent exposure in participant's hair taken at the evaluation. The evaluation consisted of short (~2 h) and long (overnight) Holter recordings obtained in 514 and 203 participants, respectively. Multivariable analyses examined the association of prenatal and recent MeHg exposure (in separate models) with time-domain and frequency-domain HRV parameters in different physiologic circumstances: supine position, standing position, mental stress when undergoing a mathematics test, sleep, and long recording. Prenatal MeHg exposure was not associated with any of the 23 HRV parameters studied after adjustment for multiplicity. The recent MeHg showed a trend toward significance only for few variables in the primary model. However, after additional adjustment for activity levels, polyunsaturated fatty acids, and multiplicity none were significant after a Bonferroni adjustment. In conclusion, prenatal and recent MeHg exposure had no consistent pattern of associations to support the hypothesis that they are adversely associated with heart rate variability in this study population that consumes large amounts of fish.
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Affiliation(s)
- Wojciech Zareba
- Heart Research, Cardiology Division, University of Rochester Medical Center, Rochester, NY, United States of America.
| | - Sally W Thurston
- Department of Biostatistics and Computational Biology; University of Rochester Medical Center, Rochester, NY, United States of America
| | - Grazyna Zareba
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Jean Philippe Couderc
- Heart Research, Cardiology Division, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Katie Evans
- Department of Biostatistics and Computational Biology; University of Rochester Medical Center, Rochester, NY, United States of America
| | - Jean Xia
- Heart Research, Cardiology Division, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Gene E Watson
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States of America; Eastman Institute for Oral Health, University of Rochester, Rochester, NY, United States of America
| | - J J Strain
- University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Emeir McSorley
- University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Alison Yeates
- University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Maria Mulhern
- University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | | | - Pascal Bovet
- University Institute of Social and Preventive Medicine, Lausanne, Switzerland
| | - Edwin van Wijngaarden
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States of America; Department of Public Health Sciences, University of Rochester Medical Center, Rochester, NY, United States of America; Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, United States of America; Eastman Institute for Oral Health, University of Rochester, Rochester, NY, United States of America
| | - Philip W Davidson
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States of America; Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Gary J Myers
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, United States of America; Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States of America; Department of Neurology, University of Rochester Medical Center, Rochester, NY, United States of America
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7
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Assessment of Cardiac Autonomic Function in Relation to Methylmercury Neurotoxicity. TOXICS 2018; 6:toxics6030038. [PMID: 30036985 PMCID: PMC6161203 DOI: 10.3390/toxics6030038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 07/12/2018] [Accepted: 07/18/2018] [Indexed: 11/17/2022]
Abstract
After the European Food Safety Authority reviewed reports of methylmercury and heart rate variability (HRV) in 2012, the panel concluded that, although some studies of cardiac autonomy suggested an autonomic effect of methylmercury, the results were inconsistent among studies and the implications for health were unclear. In this study, we reconsider this association by adding a perspective on the physiological context. Cardiovascular rhythmicity is usually studied within different frequency domains of HRV. Three spectral components are usually detected; in humans these are centered at <0.04 Hz, 0.15 Hz (LF), and 0.3 Hz (HF). LF and HF (sympathetic and parasympathetic activities, respectively) are evaluated in terms of frequency and power. By searching PubMed, we identified 13 studies examining the effect of methylmercury exposure on HRV in human populations in the Faroe Islands, the Seychelles and other countries. Considering both reduced HRV and sympathodominant state (i.e., lower HF, higher LF, or higher LF/HF ratio) as autonomic abnormality, eight of them showed the significant association with methylmercury exposure. Five studies failed to demonstrate any significant association. In conclusion, these data suggest that increased methylmercury exposure was consistently associated with autonomic abnormality, though the influence of methylmercury on HRV (e.g., LF) might differ for prenatal and postnatal exposures. The results with HRV should be included in the risk characterization of methylmercury. The HRV parameters calculated by frequency domain analysis appear to be more sensitive to methylmercury exposure than those by time domain analysis.
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8
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Gump BB, Dykas MJ, MacKenzie JA, Dumas AK, Hruska B, Ewart CK, Parsons PJ, Palmer CD, Bendinskas K. Background lead and mercury exposures: Psychological and behavioral problems in children. ENVIRONMENTAL RESEARCH 2017; 158:576-582. [PMID: 28715786 PMCID: PMC5562507 DOI: 10.1016/j.envres.2017.06.033] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 05/29/2017] [Accepted: 06/27/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND The potential harm from exposure to nonessential metals, particularly mercury (Hg) and lead (Pb), has been the focus of research for years. Initial interest focused on relatively high exposures; however, recent evidence suggests that even background exposures might have adverse consequences for child development. Identifying the extent of these consequences is now a priority. METHODS We assessed blood Pb and Hg levels in a biracial sample of 9-11 year-old children (N = 203). Neurodevelopment and psychological functioning assessments included hostility, disruptive behaviors, emotion regulation, and autism spectrum disorder behaviors. Parasympathetic (vagal) responses to acute stress were indexed by heart rate variability (HRV) at rest and during stress. RESULTS With increasing Pb levels, children exhibit higher levels of hostile distrust and oppositional defiant behaviors, were more dissatisfied and uncertain about their emotions, and had difficulties with communication. These significant associations were found within a range of blood Pb levels from 0.19 to 3.25μg/dL, well below the "reference value" for children of >5μg/dL. Vagal reactivity interacted with Hg such that increasing Hg was associated with increasing autism spectrum behaviors for those children with sustained vagal tone during acute stress. CONCLUSIONS This study is the first to demonstrate an association between very low-level Pb exposure and fundamental psychological mechanisms that might explain prior associations with more complex outcomes such as delinquency. Analyses of vagal reactivity yielded entirely novel associations suggesting that Hg may increase autism spectrum behaviors in children with sustained vagal tone during acute stress. The novelty of these later findings requires additional research for confirmation and the cross-sectional nature of the data caution against assumptions of causality without further research.
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Affiliation(s)
- Brooks B Gump
- Department of Public Health, Food Studies, and Nutrition, Syracuse University, United States.
| | - Matthew J Dykas
- Department of Psychology, State University of New York College at Oswego, United States
| | - James A MacKenzie
- Department of Biological Sciences, State University of New York College at Oswego, United States
| | - Amy K Dumas
- Department of Public Health, Food Studies, and Nutrition, Syracuse University, United States
| | - Bryce Hruska
- Department of Public Health, Food Studies, and Nutrition, Syracuse University, United States
| | - Craig K Ewart
- Department of Psychology, Syracuse University, United States
| | - Patrick J Parsons
- Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, United States; Department of Environmental Health Sciences, School of Public Health, The University at Albany, United States
| | - Christopher D Palmer
- Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, United States; Department of Environmental Health Sciences, School of Public Health, The University at Albany, United States
| | - Kestutis Bendinskas
- Department of Chemistry, State University of New York College at Oswego, United States
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9
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Karita K, Sakamoto M, Yoshida M, Tatsuta N, Nakai K, Iwai-Shimada M, Iwata T, Maeda E, Yaginuma-Sakurai K, Satoh H, Murata K. [Recent Epidemiological Studies on Methylmercury, Mercury and Selenium]. Nihon Eiseigaku Zasshi 2016; 71:236-251. [PMID: 27725427 DOI: 10.1265/jjh.71.236] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
More than sixty years has passed since the outbreak of Minamata disease, and high-level methylmercury contaminations now seem nonexistent in Japan. However, mercury has been continuously discharged from natural sources and industrial activities, and the health effects on children susceptible to methylmercury exposure at low levels, in addition to mercury contamination from mercury or gold mining areas in developing countries, become a worldwide concern. In this article, we provide a recent overview of epidemiological studies regarding methylmercury and mercury. The following findings were obtained. (1) Many papers on exposure assessment of methylmercury/mercury have been published since the Minamata Convention on Mercury was adopted in 2013. (2) The most crucial problem is child developmental neurotoxicity resulting from prenatal exposure to methylmercury, but its precise assessment seems to be difficult because most of such effects are neither severe nor specific. (3) Several problems raised in birth cohort studies (e.g., whether IQ deficits due to prenatal methylmercury exposure remain when the children become adults, or whether the postnatal exposure at low levels also causes such adverse effects in children) remain unsolved. (4) Concurrent exposure models of methylmercury, lead, polychlorinated biphenyls, aresenic, and organochlorine pesticides, as well as possible antagonists such as polyunsaturated fatty acids and selenium, should be considered in the study design because the exposure levels of methylmercury are extremely low in developed countries. (5) Further animal experiments and molecular biological studies, in addition to human studies, are required to clarify the mechanism of methylmercury toxicity.
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Affiliation(s)
- Kanae Karita
- Department of Hygiene and Public Health, Kyorin University School of Medicine
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10
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Omanwar S, Fahim M. Mercury Exposure and Endothelial Dysfunction: An Interplay Between Nitric Oxide and Oxidative Stress. Int J Toxicol 2015; 34:300-7. [PMID: 26060268 DOI: 10.1177/1091581815589766] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Vascular endothelium plays a vital role in the organization and function of the blood vessel and maintains homeostasis of the circulatory system and normal arterial function. Functional disruption of the endothelium is recognized as the beginning event that triggers the development of consequent cardiovascular disease (CVD) including atherosclerosis and coronary heart disease. There is a growing data associating mercury exposure with endothelial dysfunction and higher risk of CVD. This review explores and evaluates the impact of mercury exposure on CVD and endothelial function, highlighting the interplay of nitric oxide and oxidative stress.
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Affiliation(s)
- Swati Omanwar
- School of Sciences, Indira Gandhi National Open University, New Delhi, India
| | - M Fahim
- Hamdard Institute of Medical Science and Research, Hamdard University, New Delhi, India
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