Abstract

Exposure of workers to ethylenebisdithiocarbamates (EBDCs; maneb or mancozeb) in 29 potato farms was evaluated during the control of potato late blight. Concentrations of EBDCs and ethylenethiourea (ETU), an impurity and degradation product in EBDC formulations, in ambient air were evaluated during pesticide application. Biological monitoring of exposure to EBDCs was carried out by measuring the concentrations of ETU, a metabolite of EBDCs, in urine for 22 days after the end of the exposure. The estimated inhaled doses of ETU and EBDCs during the average four hour application period were 0.07 and 1.8 micrograms/kg, respectively. Only 1-10% of ETU on the clothes reached the skin. The creatinine corrected concentrations of ETU in urine were 0.1-2.5 micrograms/mmol creatinine 24 hours after exposure ended. The estimated half life for eliminating ETU through the kidneys was close to 100 hours. These results indicate that the measurement of ETU in urine is suitable for biological monitoring of exposure to EBDCs.