Abstract: By using model Caenorhabditis elegans, the toxicity of purified terephthalic acid (PTA) wastewater was evaluated through a battery of biotest, including life span, days of 50% lethal, generation time, brood size, head thrashes, and body bends. The results revealed that compared with control, the life span and generation time of C. elegans exposed to 660 mg PTA·L^-1 were delayed to some degree, and its head thrashes and body bends were inhibited. The procreation function of C. elegans exposed to PTA wastewater was greatly ffected, with the brood size being as low as 25% of the normal one. The most sensitive indicator, brood size of C. elegans, might be a potential indicator in evaluating PTA wastewater toxicity.

Key words: Farmland, Water and fertilizer input. Rational input range. Optimum input proportion