EFFECTS OF POLLUTANTS ON LIFE-HISTORY PARAMETERS OF THE MARINE NEMATODE MONHYSTERA-DISJUNCTA

The toxicity of heavy metals (Cd, Co, Cu, Cr, Hg, Ni, Zn), acid-iron waste, pentachloro- phenol, and y-hexachlorocyclohexane on the marine nematode Monhystera disjuncta has been studied in laboratory assays. High levels of toxicants (> 1 mg/1) are necessary to cause acute effects on J2-larvae. The relative toxicity as measured by development retardation and reduction of fecundity is compared with threshold concentrations obtained from the acute tests. Fecundity is the most sensitive indicator. LC 50 values correlated significantly with the minimum concentrations of metals causing mortality and developmental inhibition. Ranking of toxicity based on fecundity does not correlate with ranking based on mortality or development rate. Monhystera disjuncta exhibits high resistance to pollutants compared with other benthic organisms. © 1991 Conseil International pour l'Exploration de la Mer.