An investigation of modifying effects of metallothionein single-nucleotide polymorphisms on the association between mercury exposure and biomarker levels

Details

• Personal Author:
  Basu N ; Franzblau, Alfred ; Gillespie B ; Goodrich JM ; Wang Y ; Werner R
• Description:
  BACKGROUND: Recent studies have suggested that several genes that mediate mercury metabolism are polymorphic in humans. OBJECTIVE: We hypothesized that single-nucleotide polymorphisms (SNPs) in metallothionein (MT) genes may underlie interindividual differences in mercury biomarker levels. We studied the potential modifying effects of MT SNPs on mercury exposure-biomarker relationships. METHODS: We measured total mercury in urine and hair samples of 515 dental professionals. We also surveyed occupational and personal exposures to dental amalgam and dietary fish consumption, from which daily methylmercury (MeHg) intake was estimated. Log-transformed urine and hair levels were modeled in multivariable linear regression separately against respective exposure surrogates, and the effect modification of 13 MT SNPs on exposure was investigated. RESULTS: The mean mercury levels in urine (1.06 µg/L) and hair (0.51 µg/g) were not significantly different from the U.S. general population (0.95 µg/L and 0.47 µg/g, respectively). The mean estimated daily MeHg intake was 0.084 µg/kg/day (range, 0-0.98 µg/kg/day), with 25% of study population intakes exceeding the current U.S. Environmental Protection Agency reference dose of 0.1 µg/kg/day. Multivariate regression analysis showed that subjects with the MT1M (rs2270836) AA genotype (n = 10) or the MT2A (rs10636) CC genotype (n = 42) had lower urinary mercury levels than did those with the MT1M or MT2A GG genotype (n = 329 and 251, respectively) after controlling for exposure and potential confounders. After controlling for MeHg intake, subjects with MT1A (rs8052394) GA and GG genotypes (n = 24) or the MT1M (rs9936741) TT genotype (n = 459) had lower hair mercury levels than did subjects with MT1A AA (n = 113) or MT1M TC and CC genotypes (n = 15), respectively. CONCLUSION: Our findings suggest that some MT genetic polymorphisms may influence mercury biomarker concentrations at levels of exposure relevant to the general population. [Description provided by NIOSH]
• Subjects:
  Biomarkers Dental Equipment Dental Offices Energy Metabolism Environmental Exposure Genetics Mercury Nucleotides Occupational Exposure Occupational Health Safety Urine Workplace

  More +
• Keywords:
  Analytical-processes Author Keywords: Biomarker Dental-materials Dentists Employee-exposure Employee-health Environmental-exposure Exposure-limits Gene-environment Interaction Genes Genetic-factors Genotoxic-effects Humans Mercury Mercury-compounds Metabolism Metalloproteins Metallothionein Methyl-compounds Single-nucleotide Polymorphism Thiones Urinalysis Work-environment

  More +
• ISSN:
  0091-6765
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Michigan ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  120
• Issue:
  4
• NIOSHTIC Number:
  nn:20041244
• Citation:
  Environ Health Perspect 2012 Apr; 120(4):530-534
• Contact Point Address:
  A. Franzblau, Room 1835, SPH I, 1415 Washington Heights, University of Michigan School of Public Health, Ann Arbor, MI 48109-2029 USA
• Email:
  afranz@umich.edu
• CAS Registry Number:
  Mercury (CAS RN 7439-97-6) ; Methylmercury(1+) (CAS RN 22967-92-6)
• Federal Fiscal Year:
  2012
• Performing Organization:
  University of Michigan, Ann Arbor
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Environmental Health Perspectives
• End Date:
  20280630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:6255a3685382b48d17a9064b13d9acd8c5a8a629efd47eedafaf2e3a46b913a44eb8940d006c19acc7bcf0b04881e8315bfdea229f8c2e91114098843ecc7bfe
• Download URL:
  https://stacks.cdc.gov/view/cdc/193849/cdc_193849_DS1.pdf
• File Type:
  [PDF - 214.23 KB ]