SPIKING SEDIMENT WITH ORGANOCHLORINES FOR TOXICITY TESTING

Sediment toxicity testing integrates responses to sediment variables a nd hence does not directly indicate cause and effect. One tool for det ermining cause and effect is sediment spiking, in which relatively unc ontaminated sediment is amended with known amounts of contaminants, th en tested for toxicity. However, sediment spiking methods vary conside rably, The present study details appropriate methodologies (dry and we t spiking) for amending sediments with a range of organic contaminant concentrations. i.e., dichlorodiphenyltrichloroethane (DDT) and polych lorinated biphenyl (PCB). Target and actual concentrations were simila r. A dose response was determined for DDT, but PCB was not toxic in an acute sediment toxicity test. Chronic testing of these same sediments is reported in a companion article in this issue.