Potential factors affecting chronic chemical intolerance associated with constitutional predisposition or lifestyle and environment during childhood: From a six-year follow-up study

Objective: The Japanese chemical intolerance (JCI) study was conducted in January 2012 with a cohort of 7245 adults from population-based sampling. This study aimed to investigate the childhood constitutional and envi-ronmental factors involved in the development of chronic CI from the prospective cohort study. Methods: In the cohort, 4683 persons were identified after six years. Self-reported questionnaires were admin-istered to the subjects to obtain information on CI status; medical history; constitution, lifestyle, and housing environment during childhood; and recent psychosomatic states. We assessed the differences between in-dividuals with persisting CI status during the follow-up (defined as chronic CI) and controls not having CI status during the follow-up. Results: A total of 2500 individuals responded. Multiple logistic regression analyses revealed significant associ-ations between chronic CI and motion sickness to car or bus and allergic conjunctivitis during childhood. Sig-nificant associations between a possible increased risk of CI and the existence of high-voltage power lines close to housing, the use of vinyl covering in wall material, the use of strong perfume by a family member, and the experience of stinky odor of paint or wax at elementary school were observed. However, the use of carpet in floor material and plaster coating in wall material was associated with a possible decreased risk of CI. Conclusions: Some potential constitutional predisposition from childhood, including inherent susceptibility in the autonomic nervous system may be involved in the development of CI.

Automated summary

The study investigated the childhood constitutional and environmental factors involved in the development of chronic chemical intolerance. Significant associations were found between chronic CI and motion sickness to car or bus and allergic conjunctivitis during childhood, as well as potential risks like high-voltage power lines and strong perfume use. However, the use of carpet in floor material and plaster coating in wall material seemed to decrease the risk of CI.