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.
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.

To investigate the problems confronting the present health care system for the elderly in depopulated areas of Japan, we examined the living conditions of solitary aged people in two rural communities, Sada and Koryo, Shimane Prefecture, where the percentage of aged population is the highest among all the prefectures in Japan. Just as community characteristics ofthe two areas are different from each other, so are the features of the elderly's health needs.
Sada is a mountainous agricultural community, where the acreage of cultivated land per household is relatively large. As many families are composed of three generations, only a small number of aged people are living by themselves.
Koryo is a urbanized agricultural community on the outskirts of Izumo City. As the acreage of cultivated land per household is narrower, the average number of family members is smaller, and the percentage of the elderly, especially female, living alone is remarkable.
In Sada as well as Koryo the solitary life of the elderly mostly resulted from the death of their spouse. Their daily contact with their children is scarce, because most childrenlive in big cities far away from their parent's home. The rate of the solitary elderly whose children and their family will return home in future is 27.0% in Sada and 43.4% in Koryo.
Most of the social problems the solitary elderly face are derived from strained household economy. The rate of the elderly whose living expenses are less than 60, 000 yen a month is 41.2% in Sada and 31.6% in Koryo. As the economic resources of the solitary elderly are generally meager, the community should gear up to meet their economic needs.