公衆衛生80巻4号

2016年04月発行

連載 ［講座］子どもを取り巻く環境と健康・14 児の精神神経発達と環境化学物質(1)

水銀，農薬，PCB曝露—東北スタディの成果ほか

著者： 龍田希¹ 仲井邦彦¹

所属機関： ¹東北大学大学院医学系研究科発達環境医学分野

ページ範囲：P.303 - P.308

　メチル水銀は強力な神経毒であり，かつてはわが国で水俣病の原因となったことで知られる．その後，水銀による環境汚染対策が進み，国内ではそのような重大な健康被害は姿を消したが，魚摂取による低濃度のメチル水銀曝露は未だに継続している．メチル水銀と同様にポリ塩化ビフェニル(Polychlorinated Biphenyl;PCB)や有機塩素系農薬なども環境中で難分解性であり生物濃縮を受けることからその曝露影響が重要な課題となっている．これらの化学物質を，ヒトは主に食事から取り込む．その曝露量は低レベルであるものの，海外の先行研究からは健康リスクが懸念されている．われわれは，これらの化学物質曝露に起因した健康影響をわが国独自のデータで検証することが必要と考え，出生コーホート調査(東北スタディ)を進めてきた．本稿では，海外の先行研究とともに東北スタディで得られた成果について紹介する．主にメチル水銀に着目し，なかでも代表的な2つのコーホート調査の研究成果について報告するが，PCBや農薬の曝露影響についても簡単に触れてみたい．

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