title: Multi-biomarker responses as indication of contaminant effects in Gambusia affinis from impacted rivers by municipal effluents.
abstract: This study investigated toxic effects in mosquitofish from two urban rivers of South China impacted by municipal effluents by using multiple biomarkers including fish morphology, biochemical indicators and transcriptional responses, and explored potential cause-effect relationship with a list of chemicals (metals, polycyclic aromatic hydrocarbons (PAHs) and pesticides). The results showed significant alterations in metallothionein (MT) protein and mRNA expression in mosquitofish collected from the two rivers and a strong association between MT protein and mRNA expression levels and heavy metals in the river water. Both ethoxyresorufin-O-deethylase (EROD) activity and cytochromes P450 1A (CYP1A) mRNA expression were significantly enhanced in mosquitofish at most sampling sites. There existed a strong correlation between EROD activity and CYP1A mRNA expression levels, but no clear correlations between these responses and PAHs in the river water possibly because of the presence of many other agonists of the aryl hydrocarbon receptor in the two rivers. Significant acetylcholinesterase (AChE) inhibition was observed in mosquitofish brain samples. The pesticides in the two rivers showed an influence on the AChE activity, which was also found to be significantly negatively correlated to fipronil concentrations. Moreover, the result also indicates that metals and pesticides present in the two rivers might cause the observed estrogenic and androgenic effects in mosquitofish. The findings from this study clearly showed morphological, biochemical and transcriptional responses in mosquitofish due to chemical contamination of the two urban rivers. This multi-biomarker approach using mosquitofish can be applied to evaluate contamination of riverine environments.
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. Electronic address: huang_gyh@sina.com.
authors.forename: Guo-Yong
authors.initials: GY
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: You-Sheng
authors.initials: YS
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Yan-Qiu
authors.initials: YQ
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Wen-Jun
authors.initials: WJ
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. Electronic address: guangguo.ying@gmail.com.
authors.forename: Guang-Guo
authors.initials: GG
authors.lastname: Ying
mesh_terms: D000818:Animals; D002681:China; D003532:Cyprinodontiformes / Q000378:metabolism*; D000074062:Environmental Biomarkers / Q000187:drug effects; D005260:Female; D008297:Male; D045483:Rivers / Q000737:chemistry; D018675:Toxicity Tests; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D000074062:Environmental Biomarkers; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Biomarker; Chemicals; Metals; Mosquitofish; Pesticides; Toxic effects