Assessment of chronic mercury exposure within the U.S. population, National Health and Nutrition Examination Survey, 1999–2006

Biometals. 2009 Dec;22(6):1103-14. doi: 10.1007/s10534-009-9261-0.

Abstract

The purpose of this study was to assess chronic mercury exposure within the US population. Time trends were analyzed for blood inorganic mercury (I-Hg) levels in 6,174 women, ages 18-49, in the NHANES, 1999-2006 data sets. Multivariate logistic regression distinguished a significant, direct correlation within the US population between I-Hg detection and years since the start of the survey (OR = 1.49, P < 0.001). Within this population, I-Hg detection rose sharply from 2% in 1999-2000 to 30% in 2005-2006. In addition, the population averaged mean I-Hg concentration rose significantly over that same period from 0.33 to 0.39 μ/L (Anova, P < 0.001). In a separate analysis, multivariate logistic regression indicated that I-Hg detection was significantly associated with age (OR = 1.02, P < 0.001). Furthermore, multivariate logistic regression revealed significant associations of both I-Hg detection and mean concentration with biomarkers for the main targets of mercury deposition and effect: the liver, immune system, and pituitary. This study provides compelling evidence that I-Hg deposition within the human body is a cumulative process, increasing with age and in the population over time, since 1999, as a result of chronic mercury exposure. Furthermore, our results indicate that I-Hg deposition is associated with the significant biological markers for main targets of exposure, deposition, and effect. Accumulation of focal I-Hg deposits within the human body due to chronic mercury exposure provides a mechanism which suggests a time dependent rise in the population risks for associated disease.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Bilirubin / analysis
  • Biomarkers / analysis
  • Female
  • Humans
  • Immune System / cytology
  • Leukocyte Count
  • Liver / chemistry
  • Logistic Models
  • Luteinizing Hormone / analysis
  • Mercury / analysis
  • Mercury / pharmacokinetics
  • Mercury / toxicity*
  • Mercury Compounds / analysis
  • Mercury Compounds / pharmacokinetics
  • Mercury Compounds / toxicity*
  • Middle Aged
  • Nutrition Surveys / trends*
  • Pituitary Gland / chemistry
  • Young Adult

Substances

  • Biomarkers
  • Mercury Compounds
  • Luteinizing Hormone
  • Mercury
  • Bilirubin