Amelioration of metal-induced toxicity in Caenorhabditis elegans: utility of chelating agents in the bioremediation of metals.

Journal Article (Journal Article)

The presence of toxic amounts of transition metals in the environment may originate from a range of human activities and natural processes. One method for the removal of toxic levels of metals is through chelation by small molecules. However, chelation is not synonymous with detoxification and may not affect the bioavailability of the metal. To test the bioavailability of chelated metals in vivo, the effects of several metal/chelator combinations were tested in the environmentally relevant organism Caenorhabditis elegans. The effect of metal exposure on nematode growth was used to determine the toxicity of cadmium, copper, nickel, and zinc. The restoration of growth to levels observed in nonexposed nematodes was used to determine the protective effects of the polydentate chelators: acetohydroxamic acid (AHA), cyclam, cysteine, calcium EDTA, desferrioxamine B, 1,2-dimethyl,3-hydroxy,4-pyridinone, and histidine. Cadmium toxicity was removed only by EDTA; copper toxicity was removed by all of the chelators except AHA; nickel toxicity was removed by cyclam, EDTA, and histidine; and zinc toxicity was removed by only EDTA. These results demonstrate the utility of polydentate chelators in the remediation of metal-contaminated systems. They also demonstrate that although the application of a chelator to metal contaminants may be effective, binding alone cannot be used to predict the level of remediation. Remediation depends on a number of factors, including metal complex speciation in the environment.

Full Text

Duke Authors

Cited Authors

  • Harrington, JM; Boyd, WA; Smith, MV; Rice, JR; Freedman, JH; Crumbliss, AL

Published Date

  • September 2012

Published In

Volume / Issue

  • 129 / 1

Start / End Page

  • 49 - 56

PubMed ID

  • 22641620

Pubmed Central ID

  • PMC3499079

Electronic International Standard Serial Number (EISSN)

  • 1096-0929

International Standard Serial Number (ISSN)

  • 1096-6080

Digital Object Identifier (DOI)

  • 10.1093/toxsci/kfs191


  • eng