Note: Single-species data [e.g., median lethal concentration (\(\pu{LC_{50}}\)) or no-observed-effect concentration (NOEC) values] for many species are fitted to a distribution relationship such as the log-normal or log-logistic curve. From this distribution of species sensitivities, a hazardous concentration (\(\pu{HC_{\textit{p}}}\)) is identified at which a certain percentage (\(p\)) of all species is likely to be affected. The most conservative form of this approach uses the lower \(\pu{95\%}\) tolerance limit of the estimated percentage to ensure that the specified level of protection is achieved