Department of Human Ecology, Okayama University Graduate School of Environmental and Life Science, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8558, Japan.
Environ Int. 2013 Sep;59:12-5. doi: 10.1016/j.envint.2013.05.002. Epub 2013 Jun 2.
Yusho disease, a polychlorinated biphenyl (PCB) and polychlorinated dibenzofuran (PCDF) mixed poisoning caused by contaminated rice oil, occurred in Japan in 1968. The evidence on reproductive outcome is limited. We therefore evaluated the regional impact of the exposure to the PCB and PCDF mixture on stillbirth rate and secondary sex ratio among the residents in two severely affected areas. We selected the regionally-affected towns of Tamanoura (n=4390 in 1970) and Naru (n=6569) in Nagasaki Prefecture, Japan, for study. We obtained data on stillbirths (spontaneous/artificial) and live-born births (total/male/female) from 1958 to 1994. For a decade and a half after the exposure, an increase in the rate of spontaneous stillbirths coincided with a decrease in the male sex ratio. Compared with the years 1958-1967, the ratios for spontaneous stillbirth rates were 2.16 (95% confidence interval: 1.58 to 2.97) for 1968-1977 and 1.80 (95% confidence interval: 1.25 to 2.60) for 1978-1987. The sex ratio (male proportion) was 0.483 (95% confidence interval: 0.457 to 0.508) in the first 10years after exposure. Exposure to a mixture of PCBs and PCDFs affected stillbirth and sex ratio for a decade and a half after the exposure.
水俣病是一种由污染的米油引起的多氯联苯（PCB）和多氯二苯并呋喃（PCDF）混合中毒，于 1968 年在日本发生。关于生殖结局的证据有限。因此，我们评估了接触 PCB 和 PCDF 混合物对两个受影响严重地区居民中死胎率和次生性别比的区域影响。我们选择了日本长崎县的有地区影响的玉野镇（1970 年有 4390 人）和名护（6569 人）进行研究。我们从 1958 年到 1994 年获得了关于死胎（自然/人工）和活产（总数/男性/女性）的数据。在接触后的十五年中，自然死胎率的增加与男性性别比例的下降同时发生。与 1958-1967 年相比，1968-1977 年的自然死胎率比为 2.16（95%置信区间：1.58 至 2.97），1978-1987 年的比为 1.80（95%置信区间：1.25 至 2.60）。接触后 10 年内的性别比（男性比例）为 0.483（95%置信区间：0.457 至 0.508）。接触 PCB 和 PCDF 的混合物会在接触后十五年内影响死胎率和性别比。
