Using Caenorhabditis elegans as a Tool for Identifying Environmental Lead Contamination: A new endpoint for relating exposures to lead risk
RICHARD TROAST AND JAMES D. WILLETT
George Mason University, Department of Environmental Science and Policy, Manassas, VA
George Mason University, Department of Molecular and Microbiology, Manassas, VA
Nematodes have been used as test organisms for many new endpoints in toxicity. Much of this has been reported in texts and in the Wormbook, published by the C.elegans research community. Key factors in measuring toxicity are the amount of toxic material absorbed and its bioavailability. This study demonstrates that there are markers for toxicity that respond to both toxicity and the bioavailability, thus providing data points to accurately express the real environmental threat. Alterations in key metabolites of the tryptophan pathway were observed in studies of C. elegans exposed to soluble and insoluble lead. The changes observed correlate to the metal’s bioavailability. Of note was the increase in anthranilic acid (AA) production with increasing exposure to bioavailable lead. This was the only metabolite of tryptophan that showed any increase in concentration. Nematodes exposed to other metals of environmental significance including cadmium, tin and arsenic at concentration levels found in contaminated soils, did not stimulate AA production in the organisms exposed. The ability to measure the levels of AA in the nematode resulting from lead contamination may provide a reliable means for predicting exposure risks to humans and other animals.
Download the full article below.