title: Exploring potential contributors to endocrine disrupting activities in Taiwan's surface waters using yeast assays and chemical analysis.
abstract: Surface waters serve as sinks for anthropogenic contaminants, including naturally occurring hormones and a variety of synthetic endocrine active substances. To investigate the presence of endocrine active contaminants in the aquatic environment in Taiwan, river water and suspended solids were analyzed by yeast assays to examine the distribution of estrogenic, androgenic, and aryl hydrocarbon receptor agonist activities. The results showed that dry-season river samples exhibited strong estrogenic and aryl hydrocarbon receptor agonist activities, but no androgenic activity was detected. Owing to the ubiquitous detection of estrogenic activities in Taiwan's surface waters, samples were further subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis for quantification of selected estrogenic compounds. LC-MS/MS results indicated that natural estrogens, such as estrone and 17β-estradiol were often the most contributing compounds for the bioassay-derived estrogenic activities due to their strong estrogenic potencies and high detection frequencies, whereas high concentrations of bisphenol A and nonylphenol also posed a threat to the aquatic ecosystems in Taiwan. Water samples eliciting strong estrogenic activities were further fractionated using high performance liquid chromatography, and significant estrogenic activities were detected in fractions containing estrone, 17β-estradiol, 17α-ethynylestradiol, and bisphenol A. Also, the presence of unidentified estrogenic compounds was found in few river water samples. Further identification of unknown endocrine active substances is necessary to better protect the aquatic environment in Taiwan.
authors: Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan. Electronic address: phchou@mail.ncku.edu.tw.
authors: Pei-Hsin
authors: PH
authors: Chou
authors: Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan.
authors: Yi-Ling
authors: YL
authors: Lin
authors: Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan.
authors: Tong-Cun
authors: TC
authors: Liu
authors: Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan.
authors: Kuang-Yu
authors: KY
authors: Chen
mesh_terms: D000728:Androgens / Q000032:analysis; D001681:Biological Assay / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D052244:Endocrine Disruptors / Q000032:analysis* / Q000633:toxicity; D004784:Environmental Monitoring / Q000379:methods*; D004967:Estrogens / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D045483:Rivers / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000378:metabolism; D013624:Taiwan; D053719:Tandem Mass Spectrometry / Q000379:methods; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D000728:Androgens; D052244:Endocrine Disruptors; D004967:Estrogens; D014874:Water Pollutants, Chemical
keywords: Aryl hydrocarbon receptor agonists; Bioassays; Endocrine active substances; Estrogenic compounds; LC–MS/MS analysis