気候変動と過剰漁獲により 海洋捕食動物における神経毒性物質の増加
Amina T Schartup1,2, Colin P Thackray3, Asif Qureshi4
1Harvard John A. Paulson School of Engineering & Applied Sciences, Harvard University, Cambridge, MA, USA. aschartup@ucsd.edu.
Nature
|August 9, 2019
まとめ
魚介類に含まれるメチル水銀 (MeHg) という神経毒は 過剰漁獲と海洋温暖化により トードとトナに増加しています MeHgの生物蓄積の増加は人間の健康を脅かし,排出量削減の努力を上回ります.
科学分野:
- 環境科学
- 海洋生物学
- 毒理学について
背景:
- 海鮮は世界の30億人を超える人の 主な栄養源です
- 魚のメチル水銀 (MeHg) は神経毒性の高い危険性があり,アメリカではトナが主な暴露源である.
- 海洋における水銀の堆積と生物増強は,高いMeHg濃度をもたらします.
研究 の 目的:
- 海洋捕食者のMeHg生物蓄積に対する生態系変化の影響を評価する.
- 過剰漁獲と海洋温暖化が商業的に重要な魚種におけるMeHgレベルにどのように影響するか評価する.
- 環境要因を考慮して,水銀の削減のための世界的な政策目標の情報提供.
主な方法:
- 海洋生態系に関する 30年以上のデータを活用したものです
- MeHgの生物蓄積をシミュレートするために生態系モデリングを使用しました.
- 大西洋のトードの食生活の変化と,大西洋のブルーフィン・トゥナの温度効果を分析した.
主要な成果:
- 過剰漁獲による食生活の変化により,1970年代から2000年代にかけてのMeHg濃度が23%増加しました.
- 海水温上昇により 組織のMeHgが56%増加する可能性があります
- 予想されるメアホーゲン濃度の増加は,海水メアホーゲン濃度の低下によって達成された減少を上回る.
結論:
- 海洋温暖化と漁業管理は 将来の海洋捕食者の MeHg レベルを左右する重要な要因です
- 現在の世界的政策目標では,継続的な生態系変化による MeHg リスクに適切に対処できない可能性があります.
- 有効な水銀削減戦略を策定するには,生態学的要因を緊急に考慮する必要がある.
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