Inherited impairment of xenobiotic metabolism is a postulated mechanism underlying environmentally associated pathogeneses such as multiple chemical sensitivity (MCS). Using the Quick Environmental Exposure and Sensitivity Inventory (QEESI), we defined people who have a strong response to chemical substances as “chemical sensitive populations (CSP).” The aim of this study is to evaluate the condition of subjects sensitive to chemicals and to analyze their genotypes in order to identify susceptibility factors in CSPs in Japanese populations.

A total of 1,084 employees of Japanese companies were surveyed using the QEESI, history of MCS, and sick house syndrome. The common genotypes of the participants were analyzed for glutathione S-transferase ( GST ) M1 , GSTT1 , aldehyde dehydrogenase2 ( ALDH2 ), and paraoxonase1 ( PON1 ) in order to identify factors in the susceptibility to sensitivity to chemicals.

Four subjects had history of diagnosis of MCS; no subjects had diagnosis of sick house syndrome. The subjects were divided into four levels according to scores of 0, 1–19, 20–39, and 40 or more on three of the QEESI subscales. In addition, we used the MCS criteria by Hojo to differentiate between cases (CSP) and controls. No significant differences in the allelic distribution of genetic polymorphisms in the GSTM1 , GSTT1 , ALDH2 or PON1 genes were found among the four levels of each subscale, or between cases and controls.

Our findings suggest that the common genotypes of GSTM1 , GSTT1 , ALDH2 , and PON1 are of little importance to CSP in a Japanese population.