Accession Number : ADA332242

Title :   Rapid Toxicity Assessment Using Micro-Eukaryotes.

Descriptive Note : Final rept. 1 Sep 95-30 Nov 96

Corporate Author : PORTLAND STATE UNIV OR

Personal Author(s) : Pratt, James R.

PDF Url : ADA332242

Report Date : DEC 1996

Pagination or Media Count : 78

Abstract : This research evaluated growth of the soil ciliate Colpoda inflata (Stokes) in rapid toxicity tests by determining sensitivity to model compounds and differences in bioavailability of toxicants in different test media. Additional studies examined the bioassay in a field situation and examined another sublethal indicator (feeding rate) in rapid toxicity tests. Related studies evaluated rapid growth tests using the alga Haematococcus lacustris using methods similar to those used in the ciliate bioassay. C. inflata was more sensitive to toxicants in an inorganic medium than in media with high organic carbon content. C. inflata growth was more sensitive overall than other rapid-screening tests and many standard acute toxicity tests. Field tests showed that the rapid test could be applied to complex mixtures in the field. Feeding rate of C. inflata was significantly reduced by copper at levels comparable to the IG50 for ciliate growth. Rapid-screening tests of H lacustris showed less sensitivity than the ciliate bioassays. When ranked with other bioassays, H lacustris was the third most tolerant. Microeukaryotes that produce dormant life-stages such as cysts are ideal for use in rapid-screening bioassays. The organisms can be stored dormant, grown on demand, and be used in a 'battery of tests' applied to site and contaminant screening.

Descriptors :   *TOXICITY, *BACTERIAL TOXINS, *INORGANIC MATERIALS, TEST AND EVALUATION, HIGH RATE, GROWTH(GENERAL), FIELD TESTS, TEST METHODS, CARBON, SENSITIVITY, MIXTURES, SOILS, COPPER, ORGANIC MATERIALS, TOXIC AGENTS, STANDARDIZATION, CONTAMINANTS, MEDIA, FEEDING, INDICATORS, BIOASSAY, SUBLETHAL DOSAGE, CYSTS, CILIATA.

Subject Categories : Toxicology
      Microbiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE