Uptake by foods of tetrachloroethylene, trichloroethylene, toluene, and benzene from air

Transition rates from air into food as well as equilibrium concentrations in air and critical foods were determined for tetrachloroethylene, trichloroethylene, benzene and toluene. From these data, maximum concentrations of the four substances in air were estimated that keep contamination of critical foods at an acceptable level. A simple and rapid method allowed us to determine the risk of food contamination from the air, e.g. in shops and kitchens, by the analysis of the air. Estimations showed that concentrations in the air of shops should not exceed 1 mg/m3 if tetrachloroethylene concentrations in foods are limited to 100 micrograms/kg (slightly higher concentrations can be accepted for the other three compounds); in kitchens of restaurants and households, even 0.3 mg/m3 cause the target concentration to be exceeded rather frequently If the limit in foods is 50 micrograms/kg, recommended maximum concentrations in air are 0.5 and 0.15 mg/m3. The data also shows that the recommended limits for concentrations in air conflict with the accepted emission limits: If emission at the accepted limit occurs near shops or households, contamination of foods far exceed that considered as tolerable.