Toxicity evaluation in a paper recycling mill e uent by coupling bioindicatorof aging with the toxicity identification evaluation method in nematodeCaenorhabditis elegans

Toxicity identification evaluation (TIE) can be used to determine the specific toxicant(s) in industrial e uents. In the current study,the authors have attempted to combine the advantages of the model organism, Caenorhabditis elegans, with the virtues of the TIEtechnique, to evaluate and identify the toxicity on aging from a paper recycling mill e uent. The results indicate that only the toxicitiesfrom mixed cellulose (MC) filtration and EDTA treatment are similar to the baseline aging toxicity, suggesting that the suspect toxicantsinducing aging toxicity may largely be the heavy metal substances in this industrial e uent. Examination of the accumulation ofintestinal autofluorescence in adult animals further confirms that the short lifespans are actually due to accelerated aging. In addition,exposure to fractions of EDTA manipulations cannot result in severe defects of reproduction and locomotion behaviors in C. elegans.Moreover, high levels of Ca, Al, and Fe in the e uent may account for the severe toxicity on aging of exposed nematodes, by TIEassay. The study here provides a new method for evaluating environmental risk and identifying toxicant(s) from the industrial e uentusing C. elegans.