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The Second European Guideline of Drinking Water was published on 3rd November 1998. Notwithstanding good German drinking water standards, as a member country of the European Union, Germany had to transfer this guideline to German law. Therefore the new German decree on drinking water (Trinkwasserverordnung - TrinkwV 2001) was published on 21st May 2001. Basing on recent toxicological findings some of the borderline values have been lowered compared to the previous version. There are problems to realize the new low borderline value for lead; therefore full realization will be ordered not till 2013. The main responsibilities as to the hygienic inspection of water-supplying installations are assigned to the Public Health Office. The owners of water supply installations are notifiable to the Public Health Office. The District with the District Community Physician is the responsible administrative authority to take measures for good and healthy drinking water quality.

Luminescent bacteria (Photobacterium phosphoreum) may be used, on the one hand, for classical toxicity tests based on the inhibition of respiration or growth and, on the other hand, their luminescence itself may become the test criterion. Such a luminescence inhibition test is commonly called a luminescent bacteria test. It may be conducted with fresh bacteria or with conserved ones. The luminescence parameter is, just like the parameter oxygen consumption, a summative parameter for undisturbed metabolic processes. Dilution series are prepared to determine the concentration level at which no inhibition of the luminous intensity is detectable in comparison with reference samples. This paper highlights the necessity of standardizing the test methods (the influence of toxic substances depends on test duration and temperature) and describes the standardized procedure established by the DIN-Arbeitskreis "Leuchtbakterientest" (Working Group of the German Institute for Standardization for the luminescent bacteria test) using freeze-dried, liquid-dried, and fresh bacteria (DIN 38,412, part 34). Results of wastewater analyses are presented and the wide range of applications is described. The choice of biotests for applications under the Federal Water Resources Management Act (Wasserhaushaltsgesetz--WHG) and the Wastewater Charges Act (Abwasserabgabengesetz--AbwAG) is discussed and the reasons for the selection of the luminescent bacteria test are explained. Within the framework of a test battery of bioassays, this test shall be used according to section 7a WHG both for evaluating the technological level of wastewater treatment and for routine monitoring of wastewater discharges. In March 1992, this test (DIN 38,412, part 34, edition March 1991) became part of the general administrative regulations for wastewater (Rahmen-Abwasser-Verwaltungsvorschrift-RAV).