The strategy of passing much of European Union (EU) waste water through a sewage treatment plant (STP) before discharging it into rivers or lakes has done much to improve the quality of our inland waterways. But we still face a very worrying situation. Environmental problems have surfaced in conjunction with the STPs and their effluent recipients, and attention has turned to human pharmaceuticals ... [Show full abstract] and endocrine active substances, in particular, as another source of potential pollutants. Trying to assess the detrimental effects of these chemicals on the aquatic environment represents an extreme cost in terms of animals, time and finance. Instead, it would be better to go back to basics and to prevent entry of these substances into our aquatic environment.