Prediction of uptake and elimination of biologically active substances in fish species

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K18206
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 64010:Environmental load and risk assessment-related
• Research Institution: Ehime University
• Principal Investigator: TANOUE RUMI 愛媛大学, 沿岸環境科学研究センター, 助教 (60767226)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: 水環境 / 化学物質 / 生物濃縮 / 体内動態 / 水生生物 / 魚類 / 移行残留性

Outline of Final Research Achievements

We determined the uptake and depuration kinetics of 78 PPCPs in three fish species, to examine the factors causing the discrepancy between the bioconcentration factors predicted on the basis of chemical lipophilicity (BCFpredicted) and the bioconcentration factors calculated from the measured PPCP concentrations in the water and fish (BCFmeasured). When comparing BCFmeasured with the BCFpredicted, similar values were observed for >58% of detected compounds. On the other hand, BCFmeasured were 2－4 orders of magnitude lower than the BCFpredicted for some compounds. This was likely due to rapid metabolism and excretion of these compounds, as the calculated half-lives were short. In contrast, 1－2 orders of magnitude higher BCFmeasured than the BCFpredicted were observed for haloperidol and chlorpheniramine, which can be explained by a fast uptake rate and slow depuration rate. The k1 values of the two compounds were relatively high, implying a specific partition to non-lipid components.

Free Research Field

環境科学

Academic Significance and Societal Importance of the Research Achievements

化学物質の生理活性は一般に生体内濃度が閾値を超えることで発現することから、生物体内濃度、特に取込・分布・代謝・排泄（以下、ADME）の理解が重要と考えられる。本研究によりPPCPsの水生生物への移行・残留性は、各生物種のADMEに顕著に依存することが明らかとなり、特異なたんぱく結合を示す物質や比較的代謝・排泄されやすい物質の存在が示された。本研究において得られた魚類におけるPPCPsのADMEに関する知見は、ADMEの機能差を考慮した生物濃縮性予測手法の確立に役立つことが予想され、生物種間の外挿・類推に付随する不確実性の低下および生態毒性・生物濃縮性試験の削減が期待できる。