The Effects of Sewage Sludge On Two Life-History Stages of Mytilus Edulis

Abstract Adult and embryos of the common mussel 'Mytilus edulis were exposed to dilutions of, respectively, whole and seawater-extracted sewage sludge. the response of adult mussels was measured as change in feeding and respiration rate after four weeks' continuous exposure, while embryo response was assessed as the percentage of normal, D-shaped larvae after 24 hours, exposure. Adult feeding rate was significantly depressed, and respiration rate significantly increased, at the lowest sludge concentration used (0.02%), and the effect appeared to be attributable to the dissolved rather than to the participate phase of the test medium. the developmental EC50 for embryos was estimated to be 0.15% sewage sludge. at dilutions of 1:600 to 1:5000, therefore, the sewage sludge investigated contained unidentified desorbable components toxic to planktonic and benthic life-history stages of a common marine invertebrate. Aerial application of fenthion, 0.0-dimethyl 0-[3-methyl-4-(methylthio)phenyl] phosphorothioate, ...