Source and transport of tricresyl phosphate (TCP) isomers in Kurose river basin

Atmospheric tricresyl phosphate (TCP) isomers in Kurose river basin were de termined, The concentrations of o-TCP and m-TCP were 0.13 and 0.09 ng m(-3) , respectively, while p-TCP was scarcely detected. Exhaust gases from motor cycles and automobiles were main sources for TCP isomers in the atmosphere. Exhaust gas from incinerator also contributes to atmospheric concentration of TCP isomers. Most of the TCP isomers could be: estimated to be sorbed t o particles, due to their low vapor pressures. The concentrations of TCP is omers were relatively high in soils collected from an open storage yard of waste PVC and near the highway and greenhouse of agricultural film. On the other hand, the concentrations were negligibly small in soil collected from the forest except for the silt-clay fraction in the soil. Dry deposition f luxes of o-TCP and m-TCP from the atmosphere was 0.2 and 0.04 mu g m(-2) d( -1), respectively. Wet deposition flux of TCP isomers during one rainfall e xceeded occasionally the dry deposition flux for two weeks. TCP isomers acc umulated in soil were discharged into river by precipitation event. Their c oncentrations increased with an increase in river flow, characteristic of a non-point source of TCP isomers. (C) 1999 Published by Elsevier Science Lt d. All rights reserved.