Exposure assessment of Organophosphate Pesticide(DDVP) Based on the Aerial Concentration in the Greenhouse / 日本農村医学会雑誌

ABSTRACT

The exposure to the organophosphate pesticide (DDVP) by sprayers was assessed based on the measurements of concentration in the greenhouse. The serum concentrations of DDVP were examined 1 hour after spraying in two men who worked in the greenhouse with gas masks. Their serum concentration level was 21.2 ng/ml and 15.0 ng/ml, respectively, while serum cholinesterase was within normal level in both men. Changes in aerial DDVP concentrations in the greenhouse were examined. The result showed a higher concentration at the lower point (0.7 m high from the ground) than at the higher point (1.4 m high from the ground). The aerial concentration remained high (0.5ppm-2.0 ppm) for two days after spraying and started to decline thereafter to 0.5 ppm or less. On the seventh day, it was undetectable.<BR>From these results, we suggest that the following precautions should be taken toprevent pesticide exposure in the greenhouse. 1. Wearing only a gas mask but also goggles are recommended when pesticides are being sprayed. 2. The work in the greenhouse should be postponed until the second day after spraying because of the aerial residue of pesticide. 3. The frequent ventilation and gas mask are necessary till the seventh day after spraying. 4. Ventilation of the zone near the ground should be done sufficiently when the workers take the half-sitting posture like “buds gathering, ” because they are exposed to higher aerial concentrations of pesticide than when they are working in a standing posture.