title: Association of markers of chronic viral hepatitis and blood mercury levels in US reproductive-age women from NHANES 2001-2008: a cross-sectional study.
abstract: BACKGROUND
  Methylmercury (MeHg) is a neurotoxin primarily found in seafood; exposures in reproductive-age women are of concern due to vulnerability of the developing fetus. MeHg is mainly eliminated via an enterohepatic cycle involving the liver and gallbladder. Dysfunction in these organs has been associated with slower MeHg elimination in laboratory animals. We hypothesized that women testing positive for chronic hepatitis B (HBV) or C (HCV), both associated with risk of longer-term liver and gallbladder impairment, would have higher total blood mercury (TBHg) concentrations than those negative for the viruses, reflecting slower MeHg elimination.
  
  
  METHODS
  Geometric mean (GM) TBHg levels from a representative sample of over 5,000 seafood-consuming, reproductive-age women from eight years (2001-2008) of the US NHANES survey were compared by viral hepatitis status (as determined by serological assay) using multiple linear regression. Adjustment was made for estimated MeHg intake from seafood consumption, social and demographic variables and other predictors.
  
  
  RESULTS
  Women with chronic HBV had 1.52 (95% CI 1.13, 2.05, p < 0.01) times the GM TBHg of women who had not come into contact with the virus. The positive association was strongest in those with most severe disease. A modest negative association was found with HCV markers.
  
  
  CONCLUSIONS
  While study design prevents inferences on causality, the finding that MeHg biomarkers differ by hepatitis status in this population suggests viral hepatitis may alter the pace of MeHg elimination. Offspring of HBV-infected seafood-consuming women may be at higher risk of MeHg-induced developmental delays than offspring of those uninfected. Possible reasons for the unanticipated negative association with HCV are explored.
authors.affiliation: Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA. msheehan@jhsph.edu
authors.forename: Mary C
authors.initials: MC
authors.lastname: Sheehan
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Burke
authors.forename: Patrick N
authors.initials: PN
authors.lastname: Breysse
authors.forename: Ana
authors.initials: A
authors.lastname: Navas-Acien
authors.forename: John
authors.initials: J
authors.lastname: McGready
authors.forename: Mary A
authors.initials: MA
authors.lastname: Fox
mesh_terms: D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D004032:Diet; D004785:Environmental Pollutants / Q000097:blood*; D005260:Female; D006525:Hepatitis, Viral, Human / Q000097:blood* / Q000453:epidemiology; D006801:Humans; D008628:Mercury / Q000097:blood*; D008875:Middle Aged; D009749:Nutrition Surveys; D017747:Seafood; D055815:Young Adult
chemical_list: D004785:Environmental Pollutants; D008628:Mercury