A PROTOCOL FOR AQUATIC HAZARD ASSESSMENT OF SELENIUM

A procedure is described for conducting an aquatic hazard assessment o f selenium, Hazard is characterized in terms of the potential for food -chain bioaccumulation and reproductive impairment in fish and aquatic birds, which are the most sensitive biological responses for estimati ng ecosystem-level impacts of selenium contamination. Five degrees of hazard are possible depending on the expected environmental concentrat ions of selenium, exposure of fish and aquatic birds to toxic concentr ations, and resultant potential for reproductive impairment. The degre e of hazard is given a numerical score: 5, high hazard; 4, moderate ha zard; 3, low hazard; 2, minimal hazard; and 1, no identifiable hazard. A separate hazard score is given to each of five ecosystem components : water, sediments, benthic macroinvertebrates, fish eggs, and aquatic bird eggs. A final hazard characterization is determined by adding in dividual scores and comparing the total to the following evaluation cr iteria: 5, no hazard; 6-8, minimal hazard; 9-11, low hazard; 12-15, mo derate hazard; 16-25, high hazard. An example is given to illustrate h ow the protocol is applied to selenium data from a typical contaminant monitoring program. (C) 1995 Academic Press, Inc.