Anti-androgenic activities of diuron and its metabolites in male Nile tilapia (Oreochromis niloticus).
Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a widely used herbicide which has been frequently detected in surface waters throughout the world. In vivo bioassay guided fractionation studies indicated that diuron may have estrogenic activity augmented by biotransformation. This study evaluated the effects of diuron and three of its metabolites on plasma hormone concentrations and spermatogenesis of the freshwater fish Nile tilapia (Oreochromis niloticus). Sexually mature male fish were exposed for 25 days to diuron, as well to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 200ng/L. Testosterone levels were decreased by diuron, but had limited effects on gonadal histology. Diuron metabolites, however, caused significant decreases in testosterone and in 11-ketotestosterone, gonadosomatic index, diameter of seminiferous tubules and in the mean percentages of germ cells (spermatids and spermatozoa). We conclude that these metabolites have antiandrogenic activity to male Nile tilapia, potentially causing reproductive impairment in male fish.
Department of Animal Biology, Universidade Estadual Paulista (IBILCE/UNESP), Rua Cristóvão Colombo, 2265, CEP - 15054-000, São José do Rio Preto, SP, Brazil.
Thiago Scremin Boscolo
TS
Pereira
Department of Animal Biology, Universidade Estadual Paulista (IBILCE/UNESP), Rua Cristóvão Colombo, 2265, CEP - 15054-000, São José do Rio Preto, SP, Brazil.
Camila Nomura Pereira
CN
Boscolo
Department of Chemistry and Environmental Sciences, Universidade Estadual Paulista (IBILCE/UNESP), Rua Cristóvão Colombo, 2265, CEP - 15054-000, São José do Rio Preto, SP, Brazil.
Danilo Grünig Humberto da
DG
Silva
Department of Aquaculture, Universidade Estadual Paulista (CAUNESP), Via de Acesso Prof. Paulo Donato Castelane, s/n. CEP - 14884-900, Jaboticabal, SP, Brazil.
Sergio Ricardo
SR
Batlouni
Department of Environmental Sciences, University of California, 3401 Watkins Dr, Riverside, CA 92521, USA.
Daniel
D
Schlenk
Department of Chemistry and Environmental Sciences, Universidade Estadual Paulista (IBILCE/UNESP), Rua Cristóvão Colombo, 2265, CEP - 15054-000, São José do Rio Preto, SP, Brazil. Electronic address: ealmeida@ibilce.unesp.br.
Eduardo Alves de
EA
Almeida
D000726:Androgen Antagonists / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D000818:Animals; D001681:Biological Assay; D023681:Cichlids / Q000502:physiology*; D004237:Diuron / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D005618:Fresh Water; D006066:Gonads / Q000187:drug effects; D006540:Herbicides / Q000378:metabolism; D008297:Male; D010671:Phenylurea Compounds / Q000378:metabolism / Q000633:toxicity; D013091:Spermatogenesis / Q000187:drug effects; D013739:Testosterone / Q000031:analogs & derivatives / Q000378:metabolism / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity
C561340:3,4-dichlorophenylurea; D000726:Androgen Antagonists; D006540:Herbicides; D010671:Phenylurea Compounds; D014874:Water Pollutants, Chemical; D013739:Testosterone; D004237:Diuron; C003600:11-ketotestosterone
Andi–androgenic effects; Diuron; Diuron metabolites; Gametogenesis; Nile tilapia