酸化河川における多核硫化物群として鉄,銅,亜鉛の複合性の証拠
1College of Marine Studies, University of Delaware, 19958, USA. trozan@udel.edu
Nature
|September 6, 2000
まとめ
以前は見過ごされていた溶けた金属硫化物は,河川で見つかりました. これらの安定した,複雑な金属硫化物構造は,淡水生態系における微量金属の毒性を調節する可能性があります.
科学分野:
- 環境化学 環境化学
- 地質化学 地質化学
- アクアティック・ケミストリー
背景:
- 淡水の微量金属の生物利用性と毒性は,溶けた有機物質との複合によって影響を受けます.
- 微量金属の結合における無機硫化物の役割は,酸化水中の持久性が低いため,しばしば無視されています.
研究 の 目的:
- 河川系における溶解した無機硫化物の存在と性質を調査する.
- 硫化物が,銅,鉄,亜鉛などの主要な微量金属とどの程度複合しているかを判断する.
主な方法:
- コネチカット州とメリーランド州から採取した河川水の溶けた硫化物濃度の分析.
- フーリエ変換質量スペクトロメトリ (FTMS) を使用した金属硫化物複合体の定量化.
主要な成果:
- 溶解した硫化物のナノモラー濃度が検出され,その90%以上が銅,鉄,亜鉛によって複雑化されています.
- これらの金属硫化物複合体は,溶解した金属の総量 (Fe/Znでは20%まで,Cuでは45%まで) の有意な割合を占めていた.
- FTMSは,単純なプロトンの種ではなく,より高いレベルの,プロトンのない硫化物クラスター (例えば,M3S3,M4S6) を特定しました.
結論:
- 溶解した金属硫化物は,酸化河川系に存在し,安定した複雑な構造を形成します.
- これらの安定した金属硫化物複合体は,銀,カドミウム,水銀などの非常に有毒なものを含む微量金属の生物利用可能性と毒性を制御する上で重要な役割を果たす可能性があります.
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