International trends in bioassay use for effluent management.

The use of effluent bioassays in various international jurisdictions is reviewed, resulting in an analysis of themes and trends in: regulatory use, different uses of bioassays in meeting protection goals, different types of bioassays, bioassay test variability, statistical design, use of effluent bioassays to predict receiving environment effects, and uptake of effluent bioassay testing by developing countries. Current effluent bioassay use by jurisdictions in North America, the European Union, and Asia/Pacific is described. The historical trend for many jurisdictions has been to start with chemical hazard-based systems, then add effluent bioassays (first lethal, then sublethal measures) and then use receiving environment evaluations to predict or measure impacts.

Temporal and spatial trends of PCB congeners in UK gannet eggs.

Gannet (Sula bassana) eggs collected from Ailsa Craig, Western Scotland between 1977-1998 have been analyzed retrospectively for several PCB congeners. Concentrations of a range of congeners were determined in 8-10 eggs analyzed separately for several individual years. All congeners declined in concentrations throughout the time period, but the rates of decline differed for different congeners.