Terrestrial test methods for plants and soil invertebrates

Tests were developed to assess toxicity of contaminated site soils to plants and soil invertebrates. The tests encompassed methods to evaluate contamination levels that were acutely toxic to plants, earthworms, and springtails and those levels that adversely affected growth and reproduction after longer exposure durations. The methods were designed to use test species and soils relevant to Canadian environments.; Several approaches to site soil assessment were examined to ultimately produce scientifically defensible methods and species for two test batteries. The approaches included direct assessment of site soils, dilution of site soils with control soils, and amendment of control soils with a contaminant. The test batteries differed primarily with respect to the sensitivities of the test species. The test battery for soil quality criteria development included relatively sensitive species whereas those species comprising the test battery for ecological risk assessment represented a range of sensitivities.; The unique aspects of the research include: (1) determination of the relative sensitivities of thirty species of plants to boric acid; (2) development of a process and rationale for test species selection; (3) the parameterization of four non-linear regression models to include any ICp and the associated 95% confidence intervals and their application to continuous data sets; (4) establishment of performance criteria for specific test species and validity criteria for test acceptability; (5) toxicity assessment of condensate- and amine/glycol-contaminated soils to ten plant species; (6) method modifications required for specific soil types, chemicals, or contamination problems; (7) development of a 65-d reproduction test with Eisenia andrei; (8) development of a 72-h test that measured the avoidance response of earthworms to contaminated soils or soils spiked with chemicals; (9) determination of the relationship between the results of the avoidance-response test and the earthworm reproduction test; (10) development of 7-d acute and 35-d chronic toxicity tests with the springtail Onychiurus folsomi; and, (11) investigation of a white pot worm (Enchytraeus albidus) as a suitable test species. Described in this thesis is the research relating to the development of plant test methods (i.e., the first five aforementioned initiatives) and the relationship between the results of the avoidance-response test with earthworms and the earthworm reproduction test.