Effect of thallium on phototactic behaviour in Daphnia magna.

Thallium (Tl) is a trace metal enriched in wastewaters associated with mining and smelting of base metals. The toxicity of Tl to aquatic biota is poorly understood, particularly with respect to its sublethal effects. In this study, phototactic behavioural responses of naïve (i.

Chronic toxicity of waterborne thallium to Daphnia magna.

There is limited information regarding the toxicity of the trace element thallium (Tl) to aquatic biota, most of which assesses acute toxicity and bioaccumulation. The relative lack of chronic Tl toxicity data compromises the establishment of water quality criteria for this trace metal. In the presented work, chronic toxicity endpoints (final body weight (a proxy measure of growth), survival, and reproduction) and Tl body burden were measured in the freshwater crustacean Daphnia magna during a 21-day exposure to dissolved Tl.

Non-invasive methods to measure inter-renal function in aquatic salamanders-correlating fecal corticosterone to the environmental and physiologic conditions of captive .

This study sought to develop non-invasive techniques to monitor glucocorticoids in captive as a means to correlate inter-renal gland function in relation to environmental and physiological changes. Six individually housed breeding pairs of captive were subjected to seasonal changes in water temperature (30°F temperature differential) to stimulate natural breeding, specifically spermatophore deposition and oviposition. An enzyme immunoassay was validated for the measurement of faecal corticosterone metabolites (CMs) by exhibiting parallelism and accuracy to the standard curve.

The Effect of Major Ions and Dissolved Organic Matter on Complexation and Toxicity of Dissolved Thallium to Daphnia magna.

Thallium (Tl) is a trace element associated with base metal mining and processing, but little is known regarding how its toxicity is influenced by water chemistry. In the present study, the 48-h median lethal concentration (LC50) of Tl to Daphnia magna was determined in a standard laboratory water, and toxicity was reassessed under conditions of varying cation (Ca , K , Na ), anion (Cl , HCO ), and dissolved organic matter (DOM) concentrations. The calculated 48-h LC50 of 1.