海河干流水体中有机磷酸酯的污染特征与生态风险评估OA

[Background]Organophosphate esters(OPEs)are a class of emerging persistent organic pollutants widely used as flame retardants and plasticizers.Investigating their occurrence and ecological risks in aquatic environments is essential for the water quality monitoring and precise manage-ment of the Haihe River. [Objective]To develop and validate an efficient and accurate liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for the simultaneous determination of 16 OPEs in wa-ter,to systematically investigate their spatiotemporal occurrence and ecological risks in the mainstream of the Haihe River,and to provide robust data to support local water environment governance. [Methods]Surface water samples were collected from the mainstream of the Haihe River across seven sampling campaigns in 2025:at the end of each quarter(March,June,September,and De-cember),and during the normal(May),wet(August),and dry(November)seasons.Target OPE concentrations were determined using the established LC-MS/MS method.The spatiotemporal distribution of OPEs were revealed by cluster analysis and Spearman correlation analysis using SPSS 27.0.Ecological risks were evaluated using the risk quotient(RQ)method. [Results]All 16 target OPEs were detected in the mainstream of the Haihe River.The total OPE concentration ranged from 60.1 to 2.37×103 ng·L-1,with a median of 437 ng·L-1 and a mean of 502 ng·L-1.Halogenated OPEs were the dominant pollutants,accounting for 74.4%of the total OPE load.Total concentrations exhibited significant seasonal variations,peaking in the summer(wet season)and reaching their lowest in winter(dry season).The ecological risk assessment indicated that most individual OPEs posed low risks to aquatic organisms,but the aromatic compound 2-ethylhexyl diphenyl phosphate(EHDPP)exhibited high risks(RQ>1)to crustaceans at specific sampling sites(S13,S15)in the Binhai New Area during the wet season. [Conclusion]The mainstream of the Haihe River is ubiquitously contaminated by OPEs at levels comparable to other major water bodies in China,posing an overall low ecological risk.However,the dominance of halogenated OPEs,elevated pollution levels during the wet season,and localized high risks posed by EHDPP suggest that continuous monitoring and targeted management of OPEs in the Haihe River are imperative to safeguard the health of the aquatic ecosystem.