母乳におけるメチル水銀および無機水銀濃度の日中の変動
Nozomi Tatsuta1, Miyuki Iwai-Shimada1, Kaname Asato2
1Health and Environmental Risk Division, National Institute for Environmental Studies, Tsukuba 305-8506, Japan.
Environmental research
|September 2, 2025
まとめ
母乳のメチル水銀 (MeHg) 濃度は,母乳と母乳の間に大きく異なる. 授乳中の女性のMeHgの正確な評価のために,両方の乳の種類を採取することが推奨されます.
科学分野:
- 環境 健康
- 毒理学について
- ヒトの授乳
背景:
- ヒトの母乳におけるメチル水銀 (MeHg) 濃度および変動に関するデータは限られている.
- 水銀の種化 (総水銀 [THg],MeHg,無機水銀 [IHg]) を理解することは,幼児の健康にとって極めて重要です.
- この研究は,母乳の水銀濃度に関する情報が不足していることに焦点を当てています.
研究 の 目的:
- 母乳におけるTHg,MeHg,IHg濃度の変動を調査する.
- 前乳と後乳の水銀濃度の違いを測定する.
- MeHgの研究のために母乳サンプルを採取するための標準化された方法を提案する.
主な方法:
- 授乳中の11人の母乳サンプル (産後3~5ヶ月) を分析した.
- 高性能液体染色法と誘導結合プラズマ質量スペクトロメトリを用いて測定された水銀種.
- 前乳,後乳,昼間,昼間サンプルで評価された変化
主要な成果:
- 前乳と後乳の MeHgとTHgの濃度には大きな違いが見られた.
- MeHgの平均濃度は前乳で0. 18ng/g,後乳で0. 58ng/gであった.
- 高信頼性 (>0.9 ICC) の日中の水銀測定と,日々の変動が最小であることを示す.
結論:
- 精密なMeHg評価のために母乳のサンプル収集には前乳と後乳の両方が含まれます.
- MeHgやIHgの有意な変化は見つかりませんでした.
- 乳児の被曝に関するさらなる研究が,正確なリスク分析のために必要である.
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