Abstract
The concentrations of insecticides in vacuumed house dust were analyzed as an indicator of indoor pollution in order to investigate the indoor exposure to insecticides. Here we describe the residue levels of six kinds of insecticides found in 69 house dust samples collected around Osaka from 2011 to 2015. The insecticides in dust samples were extracted with acetone under ultrasonic waves. Cleanup of insecticides in the extract was conducted using a graphite carbon column followed by a silica gel 40 mini column. Quantitative analyses of the insecticides were performed with GC by electron-capture detection or flame photometric detection using a capillary column. Chlorpyrifos was detected in 24 out of the 69 samples at a level of <0.010 to 0.48 μg/g. Diazinon was not detected in house dust at all. Fenitrothion was detected in 41 out of the 69 samples (max: 0.29 μg/g, median: 0.010 μg/g). Permethrin concentrations (max: 13 μg/g, mean: 1.7 μg/g, median: 0.36 μg/g) detected in the dust samples were highest among the six kinds of insecticides. Higher concentrations of permethrin were detected in the house dust collected from houses which were treated with termite control agents. S-421 (bis(2,3,3,3,-tetrachloropropyl) ether) was detected in 63 out of the 69 samples (max: 0.54 μg/g, mean: 0.057 μg/g). p-Dichlorobenzene was detected in 31 out of 38 samples. The concentrations of p-dichlorobenzene in two samples were higher than four times of those which have been detected in our studies thus far.
