Autor: |
Hardy, J. T., Crecelius, E. A., Cowan, C. E., Wentsel, R. S. |
Zdroj: |
Archives of Environmental Contamination and Toxicology; September 1988, Vol. 17 Issue: 5 p575-581, 7p |
Abstrakt: |
Studies were conducted to assess the fate and potential toxicity of brass powder deposited on water surfaces. Laboratory microcosms containing lake water were used to quantify the effects of surface dose, pH, alkalinity, microbiota, and sediment binding on the availability and subsequent toxicity of Cu and Zn from brass powder. Eight days after deposition on the water surface, high concentrations of Cu and Zn remained in the aquatic surface microlayer (upper 33 µm). The concentrations of total Cu and Zn in the subsurface bulkwater were reduced by the presence of bottom sediment but were little affected by biota. Toxicity of brass powder toDaphnia magna increased with increasing surface deposition (dose) and decreased with increasing water pH and alkalinity. Little or no toxicity occurred at brass powder surface doses of 50 and 1,000 mg/m2 for low- and high-alkalinity environments, respectively. Geochemical modeling suggested that toxicity resulted from concentrations of both Cu2+ and Zn2+ ions in solution. |
Databáze: |
Supplemental Index |
Externí odkaz: |
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