Ranking for environmental hazard of the chemicals spilled in the Sandoz accident in November 1986.

In 1986, a chemical spill took place from the Sandoz plant in Basel, Switzerland, into the Rhine River. In this paper we rank the environmental hazard of eight chemicals which entered the Rhine River. The ranking procedure is performed by including fate descriptors of chemicals which were derived using the fate model EXWAT. EXWAT is a part of the model E4CHEM and is briefly described in this paper. Two ranking methods are used. The first may be described as an application of statistics, whereas the second is a graph-theoretical approach. Results from both ranking methods show that the chemicals can be divided into two groups. The most hazardous include dinitro-o-cresol, propetamphos and parathion, and the least hazardous include disulfoton, thiometon, etrimfos, metoxuron and fenitrothion