HUMAN ENVIRONMENTAL AND OCCUPATIONAL EXPOSURES TO BORIC ACID: RECONCILIATION WITH EXPERIMENTAL REPRODUCTIVE TOXICITY DATA


Bolt H. M. , Basaran N., Duydu Y.

JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A-CURRENT ISSUES, vol.75, pp.508-514, 2012 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 75
  • Publication Date: 2012
  • Doi Number: 10.1080/15287394.2012.675301
  • Title of Journal : JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A-CURRENT ISSUES
  • Page Numbers: pp.508-514

Abstract

The reproductive toxicity of boric acid and borates is a matter of current regulatory concern. Based on experimental studies in rats, no-observed-adverse-effect levels (NOAELs) were found to be 17.5 mg boron (B)/kg body weight (b.w.) for male fertility and 9.6 mg B/kg b.w. for developmental toxicity. Recently, occupational human field studies in highly exposed cohorts were reported from China and Turkey, with both studies showing negative results regarding male reproduction. A comparison of the conditions of these studies with the experimental NOAEL conditions are based on reported B blood levels, which is clearly superior to a scaling according to estimated B exposures. A comparison of estimated daily B exposure levels and measured B blood levels confirms the preference of biomonitoring data for a comparison of human field studies. In general, it appears that high environmental exposures to B are lower than possible high occupational exposures. The comparison reveals no contradiction between human and experimental reproductive toxicity data. It clearly appears that human B exposures, even in the highest exposed cohorts, are too low to reach the blood (and target tissue) concentrations that would be required to exert adverse effects on reproductive functions.