Evaluating the environmental hazard of industrial chemicals from data collected during the REACH registration process.

Registration dossiers for 11,678 industrial chemicals were retrieved from the database of the European Chemicals Agency, of which 3566 provided a numerical entry for the corresponding predicted no effect concentration for the freshwater environment (PNEC). A distribution-based examination of 2244 of these entries reveals that the average PNEC of an industrial chemical in Europe is 238nmol/L, covering a span of 9 orders of magnitude. A comparison with biocides, pesticides, pharmaceuticals and WFD-priority pollutants reveals that, in average, industrial chemicals are least hazardous (hazard ranking: industrial chemicals≪pharmaceuticals<pesticides<Water Framework Directive priority pollutants<biocides). However, 280 industrial chemicals have a lower environmental threshold than the median pesticide and 73 have a lower environmental threshold than even the median biocide. Industrial chemicals produced and/or imported in higher tonnages have, on average, higher PNECs which most likely is due to the lower assessment factors used for the PNEC determination. This pattern indicates that the initial AF of 1000 comprises a measure of conservatism. The vast majority of PNEC values are driven by EC50 and NOEC data from tests with Daphnia magna. Tests with marine species are rarely provided for the hazard characterization of industrial chemicals.