半世紀以上にわたってスウェーデン沿岸の藻類に含まれる放射性物質
Sören Mattsson1, Kristina Eriksson Stenström2, Guillaume Pédehontaa-Hiaa1
1Medical Radiation Physics Malmö, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Inga Marie Nilssons gata 47, Malmö SE-205 02, Sweden.
Radiation protection dosimetry
|August 28, 2025
まとめ
海藻 (Fucus spp.) の長期監視 スウェーデンの海岸に沿って放射性物質のレベルが変化しています. 分析によると セシウム137とプルトニウムは減少しているが,ヨウ素129とウラン236は増加している.
科学分野:
- 環境放射能モニタリング
- 海洋生態学と汚染
- 核科学と技術
背景:
- 1967年以来,SärdalのFucus serratusとFucus vesiculosusの継続的なモニタリングは,長期的なデータセットを提供します.
- スウェーデンの海岸沿いの2020年のサンプル採取は,地域の放射性核酸濃度と過去のデータを比較することを目的とした.
- 海洋生態系における放射性核酸の分布を理解することは,環境の健康と潜在的なリスクを評価するために極めて重要です.
研究 の 目的:
- Fucus spp.の様々な放射性物質の時間的変動と空間的分布を報告する. スウェーデンの海岸に沿って
- 観測された放射性核酸濃度と,核施設や過去の放射性降下物を含む,既知の排出源を相関させる.
- 新しい放出が発生した場合の将来の環境モニタリングとリスク評価のためのベースラインデータを確立する.
主な方法:
- Fucus spp の定期的な採集 複数の沿岸部から採取したサンプル
- ガンマスペクトロメトリー,低背景ベータ測定,アルファスペクトロメトリー,加速器質量スペクトロメトリーを用いた放射性核素濃度の分析.
- 核再処理工場 (セラフィールド,ハーグ),原子力発電所 (リングハルス,バーセベック),チェルノブイリ放射性降下物からの放射性物質の相関分析.
主要な成果:
- タイムシリーズのデータは,ここ数十年で137Cs,99Tc,および239+240Puの濃度が減少していることを示しています.
- 129Iと236Uのレベルが上昇することが観察され,持続的または蓄積的な源を示しています.
- 14Cの分析は20世紀半ばからの大気中の核兵器実験を超えた人類的な投入を示唆しています.
結論:
- Fucus spp の放射性核酸濃度について 複数の情報源に起因する 時間的・空間的な大きな変化を示しています
- 特定の放射性核酸の観測傾向 (例えば,129I,236Uの増加) は,継続的な監視と調査を正当化しています.
- 確立された背景データは,将来の放射性核酸の海洋環境への影響の評価に不可欠です.
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