Influence of salinity and organic carbon on the chronic toxicity of silver to mysids (Americamysis bahia) and silversides (Menidia beryllina).

Tests were conducted with mysids (Americamysis bahia) and silversides (Menidia beryllina) to evaluate the influence of salinity and organic carbon on the chronic toxicity of silver. During 7- and 28-d tests conducted at 10, 20, and 30% per hundred salinity, higher concentrations of dissolved silver generally were required to cause a chronic effect as the salinity of the seawater was increased. The 28-d mysid and silverside 20%-effective concentration values (expressed as dissolved silver) ranged from 3.

Chronic toxicity of silver to the sea urchin (Arbacia punctulata).

The chronic toxicity of silver to the sea urchin (Arbacia punctulata) was determined in 30 per thousand salinity seawater during a three-part study: A fertilization test (1-h sperm exposure), a 48-h embryo test, and a 30-d adult test. Combined data from the three tests resulted in a lowest-observed-effect concentration of 19 microg/L, a no-observed-effect concentration of 8.6 microg/L, and a maximum acceptable toxicant concentration of 13 microg/L, based on measured concentrations of dissolved silver.

Aquatic toxicity evaluation of para-methylstyrene.

The aquatic toxicity of para-methylstyrene was evaluated in acute toxicity studies using fathead minnows (Pimephales promelas), daphnids (Daphnia magna), and freshwater green algae (Selenastrum capricornutum). Static tests were performed in sealed containers with no headspace to minimize loss of this volatile compound to the atmosphere. Concentrations of para-methylstyrene in test solutions were analyzed by gas chromatography equipped with a purge and trap module and flame ionization detection.