title: Estrogenicity of organophosphorus and pyrethroid pesticides.
abstract: Although organophosphorus and pyrethroid pesticides are considered environmental contaminants, their estrogenic potentials are still ubiquitous and unclear. The present study was undertaken to evaluate the estrogenic activities of nine pesticides (phoxim, malathion, monocrotophos, dimethoate, opunal, fenvalerate, cypermethrin, permethrin, and deltamethrin) using three in vitro methods [E-Screen assay, estrogen receptor (ER) competitive binding assay, and pS2 expression assay]. All the pyrethroid pesticides tested induced MCF-7 cell proliferation significantly, while organophosphorus pesticides did not. The estrogenic potency were ranked as permethrin > fenvalerate > cypermethrin > deltamethrin. The proliferation induced by cypermethrin, permethrin, and deltamethrin was blocked by ICI 182.780, while fenvalerate only partly inhibited it. In addition, pyrethroid pesticides inhibited the binding of [3H]estradiol to ER, while the organophosphorus failed to do so. Fenvalerate, permethrin, and cypermethrin induced pS2 mRNA expression with varying potency, while there were no significant effects in deltamethrin-treated groups. Our findings provide evidence to support the idea that pyrethroid pesticides tested produce an ER-specific, agonist response. Fenvalerate induced MCF-7 cell proliferation by a mechanism not involving ER-mediated pathway. Organophosphorus pesticides tested showed no estrogenic potential. Compared with the pS2 expression assay, E-Screen was a more sensitive and useful assay for screening of the xenoestrogenic chemicals.
authors.affiliation: Institute of Toxicology, Nanjing Medical University, Nanjing, People's Republic of China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Chen
authors.forename: Jigao
authors.initials: J
authors.lastname: Xiao
authors.forename: Gang
authors.initials: G
authors.lastname: Hu
authors.forename: Jianwei
authors.initials: J
authors.lastname: Zhou
authors.forename: Hang
authors.initials: H
authors.lastname: Xiao
authors.forename: Xinru
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D001943:Breast Neoplasms; D002455:Cell Division / Q000187:drug effects; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D004965:Estrogen Antagonists / Q000494:pharmacology; D020847:Estrogen Receptor Modulators; D004968:Estrogens, Non-Steroidal / Q000633:toxicity*; D005260:Female; D000077267:Fulvestrant; D006801:Humans; D007306:Insecticides / Q000633:toxicity*; D009570:Nitriles; D009946:Organothiophosphorus Compounds; D011506:Proteins; D011722:Pyrethrins / Q000494:pharmacology / Q000633:toxicity*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000378:metabolism; D000071163:Trefoil Factor-1; D014316:Tritium; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D025521:Tumor Suppressor Proteins
chemical_list: D004965:Estrogen Antagonists; D020847:Estrogen Receptor Modulators; D004968:Estrogens, Non-Steroidal; D007306:Insecticides; D009570:Nitriles; D009946:Organothiophosphorus Compounds; D011506:Proteins; D011722:Pyrethrins; D012333:RNA, Messenger; D011960:Receptors, Estrogen; C051838:TFF1 protein, human; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins; D014316:Tritium; D000077267:Fulvestrant; D004958:Estradiol; C017690:fenvalerate