Preliminary exposure assessment of volatile chlorinated hydrocarbons in Japan

Abstract

Human exposure to dichloromethane, chloroform, carbon tetrachloride, 1,1,1- trichloroethane, trichloroethylene, and tetrachloroethylene was assessed by mathematical models. Environmental fate model (MNSEM145) was applied to evaluate their environmental concentrations in Japan and human exposure doses through inhalation of ambient air and ingestion of drinking water, milk, meat, fish, and vegetation (vegetables and fruit). Estimated exposure doses were used to calculate their human distribution by physiologically based pharmacokinetic (PB-PK) model. Calculated concentrations of the chlorinated hydrocarbons in the air, water, soil and sediment were in good agreement with values measured in Japan. Estimated human exposure doses agreed with measured values in same order of magnitude and suggested that the major exposure pathway was inhalation. Most of the chlorinated hydrocarbons absorbed in human body were estimated to be exhaled unchanged under the steady state, except that dichloromethane and trichloroethylene were rather metabolized.