Prevalence and interannual changes in multiple chemical sensitivity in Japanese workers.

Objective: We aimed to evaluate the prevalence rates and interannual fluctuations in multiple chemical sensitivity (MCS) in Japanese workers. Methods: We assessed MCS using the Quick Environmental Exposure and Sensitivity Inventory, employing both Miller and Japanese criteria. Workers of two manufacturing companies located in Kyushu, Japan, were assessed, with company A surveyed in 2003, 2006 and 2011, and company B in 2003 and 2011. Results: In company A, the Miller criteria-based MCS prevalence rate was higher in 2011 than in 2003, and according to the Japanese criteria, it was higher in 2011 than 2006. In company B, the Miller criteria-based MCS prevalence rate was lower in 2011 than in 2003. Conclusion: The results indicated that MCS exists among industrial workers in Japan. We found no statistically significant interannual changes in MCS rates. [ABSTRACT FROM AUTHOR]