Department of Epidemiology, National Institute for Minamata Disease, 4058-18 Hama, Minamata, Kumamoto 867-0008, Japan.
Ecotoxicol Environ Saf. 2010 Sep;73(6):1144-9. doi: 10.1016/j.ecoenv.2010.05.007. Epub 2010 May 21.
The present study was conducted to investigate the historical time-course changes and regional distribution of methylmercury concentrations in preserved umbilical cords collected from Minamata-area inhabitants born between 1947 and 1989. The data from Miyazaki, Tottori, Akita, Tsushima (Nagasaki), Fukuoka and Tokyo were used as controls. A total of 325 data were analyzed to estimate the temporal and spatial distribution of methylmercury among inhabitants born in the Minamata area. Elevated methylmercury concentrations (>or=1 microg/g) were mainly observed in inhabitants born between 1947 and 1968. That peak coincided with the peak of acetaldehyde production in Minamata. The methylmercury concentrations started to decrease in keeping with the decline of acetaldehyde production, which ceased in 1968, and thereafter the methylmercury levels gradually decreased to the control levels. Elevated methylmercury concentrations were first observed in the districts of Minamata, followed by Izumi, Tsunagi and Ashikita, indicating the time-course-dependent regional distributions of methylmercury pollution.
本研究旨在调查 1947 年至 1989 年间出生于水俣地区的居民保存的脐带中甲基汞浓度的历史时间变化和地域分布。宫崎、鸟取、秋田、对马（长崎）、福冈和东京的数据被用作对照。分析了总共 325 份数据，以估计出生于水俣地区的居民中甲基汞的时空分布。出生于 1947 年至 1968 年的居民中主要观察到甲基汞浓度升高（≥1μg/g）。这一高峰与水俣乙醛生产的高峰相吻合。随着乙醛生产的下降，甲基汞浓度开始下降，乙醛生产于 1968 年停止，此后甲基汞水平逐渐下降至对照水平。甲基汞浓度的升高首先在水俣地区的地区观察到，随后是泉、鹤滨和足立地区，表明甲基汞污染具有时间依赖性的地域分布。
