Which adverse effect or »xenochemicals« contaminate or endanger preferentially the drinking-water?
Geogenic constituents, residues from treatment additives and/or pipe materials as well as hydrophilic environmental contaminants prevalent in drinking-water are groups of compounds with high priority to evaluate in drinking-water. Up to a adverse (health, technical or esthetic) effect based level they are hygienically acceptable there only if a lower value is not or hardly possible to achieve, e. g. by precautionary or surrogate technical measures.
Most difficult to avoid are geogenic constituents whereas minimal values for a functionally optimized treatment and distribution of drinking-water in most cases are distinctly lower than as based purely on their adverse effect potential. Maximal values for hydrophilic »new analytes« to avoid »on site« appear acceptable »off site« in drinking-water even only in trace concentrations of maximally a few μg/l, hence at most at the level of health related precautionary values.