Effect of anthropogenic chemicals on primary production in coastal areas: elucidation of combined effects of limiting nutrient and strong light

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H03067
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 40030:Aquatic bioproduction science-related
• Research Institution: Fisheries Research and Education Agency
• Principal Investigator: Onduka Toshimitsu 国立研究開発法人水産研究・教育機構, 水産技術研究所(廿日市), 主任研究員 (00371972)
• Co-Investigator(Kenkyū-buntansha): 小原 静夏 広島大学, 統合生命科学研究科(生), 助教 (10878276) ; 小池 一彦 広島大学, 統合生命科学研究科(生), 教授 (30265722) ; 植木 尚子 岡山大学, 資源植物科学研究所, 准教授 (50622023)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 一次生産者 / 除草剤 / 抗生物質

Outline of Final Research Achievements

Anthropogenic chemicals (AC) such as antibiotics and herbicides are heavily used on land and enter coastal areas via rivers. We conducted a monitoring survey of AC in the Seto Inland Sea, the target area of this study, and clarified the characteristics of high-concentration areas, such as deep part of the bay and near sewage treatment plants. The effects of AC on marine microalgae were also examined, and it was found that diatoms are highly sensitive species and that the effects of AC are enhanced by the combined effects of AC and intense light. The ecological risk of AC was evaluated by comparing the concentrations in the environmental water studied with the previously reported predicted no-effect concentrations (PNEC). The ecological risk of antibiotics was higher in the limited high concentration area mentioned above, while the herbicide diuron was of concern over a wider area, with more than half of the samples exceeding the PNEC.

Free Research Field

環境毒性学、環境化学

Academic Significance and Societal Importance of the Research Achievements

陸域で多用される抗生物質や除草剤等の人為起源化学物質（AC）は河川などを通じて最終的に海洋に到達する。しかし、日本の沿岸海域においてACの生態リスクを評価した事例はほとんどなく、本研究で日本沿岸域におけるACの生態リスクを評価したことに意義がある。また本研究では、生態リスクが高まる湾奥部や下水処理場付近などの高濃度となる海域の特徴や藻類の生長速度を半減させる濃度などの毒性値、強光など藻類に対する毒性が強まる条件を明らかにした。これらの情報は環境省の環境リスク初期評価など、ACの生態リスクを評価する際の基礎資料として活用される事が期待される。