Human Environmental and Occupational Exposures to Boric Acid: Reconciliation with Experimental Reproductive Toxicity Data

@article{Bolt2012HumanEA,
  title={Human Environmental and Occupational Exposures to Boric Acid: Reconciliation with Experimental Reproductive Toxicity Data},
  author={Hermann M. Bolt and Nurşen Başaran and Yalçın Duydu},
  journal={Journal of Toxicology and Environmental Health, Part A},
  year={2012},
  volume={75},
  pages={508 - 514}
}
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… 
Chapter 3 – Risk Assessment of Borates in Occupational Settings
TLDR
The available epidemiological study results indicated that human boron exposure, even in the highest exposure cohorts, is too low to reach the blood concentrations that would be required to exert adverse effects on reproduction, Consequently, the borons-mediated reprotoxic effects identified in animal experiments with high doses may not be relevant to humans.
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TLDR
The protective effect of BA against oxidative DNA damage in V79 cells at 5, 10, 50, 100 and 200 μM (54, 108, 540, 1080, and 2161 ng/ml B equivalents) concentrations was proved in this in vitro study.
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TLDR
A total body of evidence has accumulated that allows to conclude that male reproductive effects are not relevant to humans, under any feasible and realistic conditions of exposure to inorganic boron compounds.
Protective effect of boric acid on lead- and cadmium-induced genotoxicity in V79 cells
TLDR
It can be suggested that boron provides an efficient protection against the induction of DNA strand breaks and micronuclei by lead and cadmium.
Recent epidemiological studies on boron exposure –contradiction between hazard and risk-based assessments
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Current data regarding the structure-toxicity relationship of boron-containing compounds.
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This mini-review summarizes two aspects of BCCs: toxicological data found with experimental models, and the scarce but increasing data about the structure-activity relationship for toxicity and therapeutic use.
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