The effect of true water hardness and alkalinity on the toxicity of Cu and U to two tropical Australian freshwater organisms

2001

Internal Report 348
Riethmuller N
Supervising Scientist Division
Department of the Environment, Water, Heritage and the Arts

About the report

The Australian and New Zealand water quality guidelines aim to supplement and modify existing criteria, which are mostly based on Northern Hemisphere toxicity data, with information relevant to Southern Hemisphere ecosystems as it became available. In the wet-dry tropics of Australia, copper (Cu) and uranium (U) are metals of particular concern, due to mining activities. Although the toxicity of Cu and U to tropical freshwater species has previously been characterised, the influence of physico-chemical parameters on toxicity has not been defined. In contrast, temperate freshwater studies have investigated the effects of various physico-chemical parameters on Cu toxicity, and to a limited extent U toxicity. The reported results however are contradictory. Thus it is recognised that the development of a model based on key water quality variables would enhance the capacity to predict the potential site-specific impacts of Cu and U in tropical ecosystems.