标题:Residual Status of Chlorpyrifos and Octachlorodipropylether in Ambient Air and Polished Rice Stock in Houses Five Years after Application for Termite Control
摘要:Indoor exposure to chlorpyrifos and 2, 3, 3, 3, 2', 3', 3', 3'-octachlorodipropylether (OCDPE, a synergist, commercial name S-421 in Japan) of residents living in two houses (B and F) treated for termite control, was investigated by examining the residual levels in ambient air and in polished rice stock in houses through five years after their application. Chlorpyrifos and OCDPE levels detected in the air of the dining room of house B ranged from 0.007 to 0.11μg/m3 and from 0.12 to 0.79μg/m3, respectively. Chlorpyrifos and OCDPE levels detected in the air of a Japanese-style room in house F ranged from 0.07 to 0.41μg/m3 and from 0.008 to 0.046μg/m3, respectively. The estimated combined daily intake of chlorpyrifos from air and rice, was around 3μg in house B and 4μg in house F, below the recommended reference dose (RfD) of 3μg/kg/d from all sources. The estimated combined daily intake of OCDPE from air and rice was approximately 48μg in house B and 0.5μg in house F. Termiticide concentration in both air and rice depended on the season, being high in summer and lower in winter. Chlorpyrifos and OCDPE levels in the indoor air in the breathing zone did not decrease during the five years after their application for termite control.