Chris Ivey

2 items:

Survival, growth and reproduction of the amphipod Hyalella azteca in 42-d water only treatments with and without the addition of bromide Poor survival, growth and reproduction of the amphipod Hyalella azteca has been observed in exposures using reconstituted waters. Previous studies have reported success in H. azteca water-only exposures with the addition of relatively high concentrations of bromide (Br). This study evaluated the influence of lower environmentally representative concentrations of Br on the response of the amphipod H. azteca in 42-d water-only exposure conditions in various reconstituted waters. Improved performance of H. azteca was observed in reconstituted waters with >0.02 mg Br/L. These tables and figures provide online supplemental information that will not be included in the journal article. Categories: Data; Types: Citation; Tags: NA, chronic testing, methods development, water-only testing
Using an inter-lab study to revise methods for conduction 10- to 42-d water or sediment toxicity tests with Hyalella azteca Studies have been conducted to refine USEPA, ASTM, and Environment Canada standard methods for conducting 42-d reproduction tests with H. azteca in water or in sediment. Modifications to the H. azteca method include better defined ionic composition requirements for exposure water (i.e., >15 mg/L of chloride and >0.02 mg/L of bromide) and improved survival, growth and reproduction with alternate diets provided as increased rations over time in water-only or whole-sediment toxicity tests. A total of 24 laboratories volunteered to participate in an inter-laboratory study evaluating the performance of H. azteca in 42-d studies in control sand or control sediment using the refined methods. Improved growth and reproduction... Types: Citation; Tags: NA, methods development

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