[Accident in the Hoechst AG company 22 February 1993. 2. Public health evaluation].

A major chemical accident occurred on 22 February 1993 at plant Griesheim of Hoechst AG Frankfurt/Germany during which approximately 11.8 tons of a chemical mixture containing mostly chlorinated nitroarenes were emitted leading to serious contaminations in Schwanheim/Goldheim, a nearby housing area. Numerous inhabitants of the contaminated area complained of irritation of eyes, skin and mucous membranes, headache and nausea, and 92 persons with moderate symptoms were reported to the National Health Department. Urine samples were collected from the inhabitants of the affected area a few days after the accident and analysed for o-nitrophenol as a representative metabolite to assess the actual uptake of pollutants. O-nitrophenol, however, was also detected in the urine of not knowingly exposed control subjects, an observation not hitherto described in literature. The median levels of o-nitrophenol were three times higher in the exposed population than in the controls. Taking into account the data on pollution measured in the environment, the reported intoxication symptoms, the results of biomonitoring, and the published literature on the components of the mixture, the following conclusions were drawn: (1) The exposure was not high enough to cause severe acute toxic effects. (2) Although the emitted mixture contained carcinogenic components according to animal experiments, the transient exposure to these chemicals does not increase the tumour risk to any measurable extent, i.e. demonstrable by epidemiological methods, especially if weighed against the permanent exposure to "normal" urban pollution.