Decades of toxicity studies have revealed that sensitivity to particular pollutants isstrongly species-specific (US EPA 2007, Grosell et al. 2007). Toxicity values can span several orders of magnitude and vary with the life stage tested, size of organisms and physiology, with closely related species tending to have a similar response(Grosell et al. 2007). Therefore a toxicity threshold found for a test species cannot necessarily be applied to other, especially phylogenetically distant, species. Given this restriction, acceptable pollutant levels for water bodies as determined by environmental agencies are usually defined by compiling results from a wide range of local organisms (ANZECC 2000, US EPA 2014).