Akagi H, Grandjean P, Takizawa Y, Weihe P
National Institute for Minamata Disease, Minamata, Kumamoto, Japan.
Environ Res. 1998 May;77(2):98-103. doi: 10.1006/enrs.1997.3822.
The methylmercury exposure of patients with congenital or infantile Minamata disease is known only from a small number of analyses of umbilical cords. Four laboratories in Japan have analyzed a total of 176 samples of umbilical cord tissue obtained from Minamata. The highest concentrations were seen in cord tissue from children born during 1950-1965, i.e., the peak period of acetaldehyde production in Minamata before installation of waste water treatment. Twenty-four samples from patients diagnosed with Minamata disease showed a median mercury concentration of 1.63 microg/g and differed significantly from levels seen in cord tissue from control children. However, children diagnosed with mental retardation had mercury concentrations in cord that were intermediate between the two other groups. Using regression coefficients obtained at a study conducted at the Faroe Islands, the median cord mercury concentration from the children with Minamata disease is estimated to correspond to about 216 microg/L cord blood and 41 microg/g in maternal hair. Based on correlations reported in the literature, the median daily mercury intake of the women whose children developed Minamata disease can then be estimated at about 225 microg. Although these children had fully developed Minamata disease, the estimates of median mercury levels are only four to five times higher than current mercury exposure limits.
先天性或婴儿型水俣病患者的甲基汞暴露情况仅通过少数脐带分析得知。日本的四个实验室共分析了从水俣病患者身上获取的176份脐带组织样本。浓度最高的出现在1950年至1965年期间出生的儿童的脐带组织中，即水俣病地区在安装废水处理设施之前乙醛产量的高峰期。24份被诊断为水俣病患者的样本显示汞浓度中位数为1.63微克/克，与对照儿童脐带组织中的水平有显著差异。然而，被诊断为智力迟钝的儿童脐带中的汞浓度处于另外两组之间。根据在法罗群岛进行的一项研究获得的回归系数，估计患有水俣病的儿童脐带汞浓度中位数约相当于脐带血中216微克/升和母体头发中41微克/克。根据文献报道的相关性，随后可以估计其孩子患水俣病的女性的汞日摄入量中位数约为225微克。尽管这些儿童已完全患上水俣病，但汞水平中位数的估计仅比当前汞暴露限值高四到五倍。
