REVIEW OF WHOLE-ORGANISM BIOASSAYS - SOIL, FRESH-WATER SEDIMENT, AND FRESH-WATER ASSESSMENT IN CANADA

Whole organism bioassays for the assessment of soil, freshwater sedime nt, and freshwater quality were evaluated for their application in the assessment and remediation of contaminated sites in Canada under the National Contaminated Sites Remediation Program. Using 3 essential and 12 desirable methodological criteria, bioassays were categorized as c urrently usable, prototype, or under development. Based on further con siderations related to bioassay application, a battery of usable scree ning and definitive tests was recommended (with suggestions for augmen tation) for each medium. Of the 18 bioassays reviewed for soil quality assessment, 6 were usable, 5 were prototypes, and 7 were under develo pment. Battery screening and definitive tests included 14-day Eisenia andrei survival, 120-hr lettuce and radish seedling emergence, and 72- hr Selenastrum capricornutum growth inhibition. Augmentation with the following bioassays was recommended: soil/freshwater bacterial growth, arthropod reproduction, earthworm reproduction, and reproduction of o ther soil-dependent organisms. Of the 9 bioassays reviewed for freshwa ter sediment quality assessment, 1 was usable, 2 were prototypes, and 6 were under development. Three bioassays in the latter two groups wer e considered usable with the imminent completion of research underway. Screening tests selected included 10-day Chironomus tentans survival, 10-day Hyalella Aztec survival, 10-day Hexagenia spp. survival, and 7 2-hr S. capricornutum growth inhibition. Definitive tests included scr eening tests, substituting 28-day H. azteca sexual maturation for 10-d ay survival. Augmentation with the following bioassays was recommended : sediment/freshwater bacterial test, 28-day Tubifex tubifex reproduct ion, and rooted aquatic plant growth. Of the 25 bioassays considered f or freshwater quality assessment, 8 were usable, 7 were prototypes, an d 10 were under development. Screening tests selected included 72-hr S . capricornutum growth inhibition; 48-hr Daphnia sp. survival, and 5- and 15-min Photobacterium phosphoreum bioluminescence. Definitive test s included first screening test, 7-day Ceriodaphnia dubia, 7-day fathe ad minnow larval survival, or 96-hr rainbow trout survival. Augmentati on with the following bioassays was recommended: Brachionus calyciflor us 24-hr survival, 48-hr reproduction; freshwater bacterial growth; an d aquatic vascular plant growth. (C) 1995 Academic Press, Inc.