Toxicity of short-chain alcohols to the nematode Caenorhabditis elegans: a comparison of endpoints.
The toxicities of 4 short-chain alcohols--namely methanol, ethanol, iso-propanol and iso-butanol--were compared in the nematode Caenorhabditis elegans using several different ecotoxicological endpoints. Range-finding tests were conducted using transgenic PC161 worms carrying a double reporter construct (GFP plus lacZ) linked to the stress-inducible hsp16-1 promoter. These tests showed little response from the GFP reporter, but gave good dose-response curves for the lacZ reporter--showing clear induction at 0.5% v/v ethanol in an overnight assay, but only at 4% in a shorter 6-h assay. Comparison of the short-term dose-response curves shows a confusing pattern of differences between the four alcohols tested, although dose-dependence is evident across at least part of the concentration range. Feeding inhibition assays are somewhat inconclusive with regard to alcohol type, although iso-butanol and iso-propanol appear more toxic than ethanol, while methanol is least toxic. To resolve some of the remaining ambiguities, we also used a fecundity assay to show that iso-propanol is more toxic than ethanol, and a lethality assay to show that iso-butanol is more toxic than iso-propanol. Most of the endpoints studied are consistent with the following order of toxicity: iso-butanol > iso-propanol > ethanol > or = methanol.
Thompson
Grace
G
Institute of Genetics, School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
de Pomerai
David I
DI
D000438:Alcohols / Q000633:toxicity*; D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000187:drug effects*; D006360:Heat-Shock Proteins / Q000096:biosynthesis*
D000438:Alcohols; D029742:Caenorhabditis elegans Proteins; D006360:Heat-Shock Proteins