Dose-response relationship between arsenic exposure and the serum enzymes for liver function tests in the individuals exposed to arsenic: a cross sectional study in Bangladesh

Environ Health. 2011 Jul 8;10:64. doi: 10.1186/1476-069X-10-64.

Abstract

Background: Chronic arsenic exposure has been shown to cause liver damage. However, serum hepatic enzyme activity as recognized on liver function tests (LFTs) showing a dose-response relationship with arsenic exposure has not yet been clearly documented. The aim of our study was to investigate the dose-response relationship between arsenic exposure and major serum enzyme marker activity associated with LFTs in the population living in arsenic-endemic areas in Bangladesh.

Methods: A total of 200 residents living in arsenic-endemic areas in Bangladesh were selected as study subjects. Arsenic concentrations in the drinking water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The study subjects were stratified into quartile groups as follows, based on concentrations of arsenic in the drinking water, as well as in subjects' hair and nails: lowest, low, medium and high. The serum hepatic enzyme activities of alkaline phosphatase (ALP), aspartate transaminase (AST) and alanine transaminase (ALT) were then assayed.

Results: Arsenic concentrations in the subjects' hair and nails were positively correlated with arsenic levels in the drinking water. As regards the exposure-response relationship with arsenic in the drinking water, the respective activities of ALP, AST and ALT were found to be significantly increased in the high-exposure groups compared to the lowest-exposure groups before and after adjustments were made for different covariates. With internal exposure markers (arsenic in hair and nails), the ALP, AST and ALT activity profiles assumed a similar shape of dose-response relationship, with very few differences seen in the higher groups compared to the lowest group, most likely due to the temporalities of exposure metrics.

Conclusions: The present study demonstrated that arsenic concentrations in the drinking water were strongly correlated with arsenic concentrations in the subjects' hair and nails. Further, this study revealed a novel exposure- and dose- response relationship between arsenic exposure metrics and serum hepatic enzyme activity. Elevated serum hepatic enzyme activities in the higher exposure gradients provided new insights into arsenic-induced liver toxicity that might be helpful for the early prognosis of arsenic-induced liver diseases.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alanine Transaminase / blood
  • Alkaline Phosphatase / blood
  • Arsenic / analysis*
  • Arsenic Poisoning / blood*
  • Arsenic Poisoning / epidemiology
  • Aspartate Aminotransferases / blood
  • Bangladesh / epidemiology
  • Biomarkers / blood
  • Cross-Sectional Studies
  • Dose-Response Relationship, Drug
  • Environmental Monitoring
  • Epidemiological Monitoring
  • Female
  • Hair / chemistry
  • Humans
  • Liver / enzymology
  • Liver Function Tests / methods*
  • Male
  • Middle Aged
  • Nails / chemistry
  • Water Pollutants, Chemical / analysis
  • Water Pollutants, Chemical / poisoning
  • Water Supply / analysis

Substances

  • Biomarkers
  • Water Pollutants, Chemical
  • Aspartate Aminotransferases
  • Alanine Transaminase
  • Alkaline Phosphatase
  • Arsenic