Study On The Spatial And Temporal Distribution And Risk Assessment Of Steroid Hormones In Guangdong Key Bays

Steroid hormones in the environment are a typical class of environmental endocrine disruptors that may cause harm to organisms at very low concentrations(<1ng/L).Therefore,residual steroid hormones in the environment may pose a potential threat to environmental organisms,and it has been a hot spot for academic research as an important member of environmental hormones.The investigation of the pollution of various substances in the marine environment has been carried out gradually,but the data investigation of steroid hormones is only limited to some sea areas,and the data and research about steroid hormones in other key bays are still limited,and a large amount of research data is still needed to support the ecological risk assessment of steroid hormone pollutants in the marine environment.In this thesis,10 key bays,including Zhenhai Bay,Guanghai Bay,Pearl River Estuary,Dapeng Bay,Daya Bay,Honghai Bay,Shenquan Bay,Guangao Bay,Shantou Port and Zhelin Bay,were selected for the study,and the distribution characteristics and ecological risks of steroid hormones in seawater,marine sediments and marine organisms were studied.In this study,43 steroid hormones were analyzed in seawater,marine sediments and organisms in 10 key bays of Guangdong Province by liquid chromatography tandem mass spectrometry(LC-MS/MS),and their pollution levels,distribution characteristics and ecological risks in Guangdong waters were investigated.(1)A total of 31 target pollutants,including 8 androgens,4 glucocorticoids,15 progestins and 4 estrogens,were detected in 68 water monitoring sites in 10 key bays in Guangdong Province,with concentrations ranging from ND(not detected)to 190.87(EDS)ng/L.The detection rates of the 31 target compounds ranged from 1.5% to 98.5%,with the 4-Androstene-3,17-dione having the The highest detection rate of 98.5% was found for androstenedione.The detection rates of DES,17α-HPA,P,and 5α-DHP were all higher than 50%.(2)A total of 16 target compounds,including 6 androgens,2 glucocorticoids,5progestins and 3 estrogens,were detected in 67 marine sediment monitoring sites in 10 key bays in Guangdong Province,with concentrations ranging from ND(not detected)to 13.44(CRL)ng/g.The detection rates of P,AED,DGT,E2 and 17β-TBL were77.9%,51.5%,27.9%,22.1% and 20.6%,respectively,while the detection rates of the remaining substances were less than 20%,with P being detected in all bays.The total average concentrations of steroid hormones detected in the sediments were ranked from high to low: progesterone > glucocorticoid > estrogen > androgen.The total concentrations of steroid hormones in the sediments of Guangdong waters in the bays were ranked from high to low: Pearl River Estuary > Guanghai Bay > Zhelin Bay >Honghai Bay > Shantou Harbor > Guangao Bay > Daya Bay > Zhenhai Bay > Dapeng Bay > Shenquan Bay.(3)A total of 21 steroid hormones,including 8 androgens,2 glucocorticoids,10 progestins and 1 estrogen,were detected in 57 biological samples(1 snail,8 shellfish and 48 fish)at 29 monitoring stations,with concentrations ranging from ND(not detected)to 62.94(CPRA)ng/g.(4)Based on ecotoxicological data,a preliminary assessment of the ecological risk of some steroid hormones in seawater and marine organisms in Guangdong waters,and a health risk assessment of human consumption of marine organisms were conducted.The results showed that the risk values of steroid hormones in seawater were,in descending order,Pearl River Estuary > Zhenhai Bay > Guangao Bay > Shantou Port >Dapeng Bay > Shenquan Bay > Guanghai Bay > Honghai Bay > Daya Bay > Zhelin Bay,and the risk values of water bodies in the Pearl River Estuary were significantly higher than those in other sea areas,and the main contributing substances were DES and 5α-DHT.In marine organisms,the synthetic progestin CPRA showed significant bioaccumulation potential in snails and shellfish.The synthetic progestins CPRA,DPN,17α-HPA and the androgen 5α-DHT showed significant bioaccumulation potential in fish.Progestins and androgens are more likely to be enriched in organisms compared to estrogens and glucocorticoids.The calculated HQ values of E2 in marine organisms were less than 1,and the consumption of E2 in fish and shellfish does not pose a risk to human health.