[Health care of workers engaged in waste water treatment. 1) The exposure conditions to organic solvents in workers engaged in waste water treatment].

In the investigation of the exposure conditions to organic solvents of workers in 35 waste water treatment facilities, it was found that these workers treated various kinds of solvents. Almost all of the facilities treated chloroform, acetone, n-hexane, methanol and carbon tetrachloride. The average exposure concentration of the workers was, however, low. Exposure concentration to organic solvents (chloroform, xylene and carbon tetrachloride) was evaluated in one of the facilities. The average concentration of the respective solvents in the workers did not exceed the threshold limit value of Japan, but the concentration calculated on the basis of combined exposure exceeded the threshold limit value. On the other hand, high concentrations of organic solvents were detected in the room where the solvents were introduced but not in the working rooms, indicating that the workers engaged in waste water treatment were mainly exposed to organic solvents in the former room where they sorted and mixed the solvents and placed them in the incinerator. In conclusion, improvement in working conditions and health care for workers engaged in waste water treatment facilities should be made in order to prevent workers from becoming intoxicated by organic solvents.