Evaluation of estrogenic activities of pesticides using an in vitro reporter gene assay

Abstract

The estrogenic activities of 32 pesticides in agricultural products were evaluated using the E-CALUX assay system developed by Xenobiotic Detection Systems Inc (North Carolina, USA). This system utilizes human ovarian carcinoma cells (BG1) stably transfected with an estrogen-responsive luciferase reporter gene plasmid. It was found that tolclofos-methyl, prothiofos, diazinon, Thiabenclazole (TBZ) and pyriproxyfen had estrogenic activity. Several pesticides are often present in agricultural products. Therefore the estrogenicity of the mixtures of two kinds of pesticides was evaluated. The activity of diazinon/tolclofos-methyl, pyriproxyfen/prothiofos and TBZ/o-phenylphenol (OPP) was increased up to 1.2 – 5.3 fold. On the other hand, chlorfluazuron, imazalil and chlorfenapyr had anti-estrogenic activity. Further, to evaluate the change in the estrogenic activity of pesticide metabolites, an experimental system was established using a rat S9 mixture. Metabolites of permethrin and OPP had no estrogenic activity, but they had weak activity after the metabolism. On the other hand, the metabolites of TBZ exhibited less estrogenic activity than the original compounds.

Keywords:

• Estrogen
• pesticide
• reporter gene assay
• 59 mixture

Acknowledgments

This work was supported in part by a Health and Labor Science Research Grant for Research on the Risk of Chemical Substances, from the Ministry of Health, Labor and Welfare, Japan.

Notes

*Present Address: Department of Engineering, Kansai University, Osaka, Suita 564-8680, Japan.

Additional information

Notes on contributors

Toshimasa Nishiyama

*Present Address: Department of Engineering, Kansai University, Osaka, Suita 564-8680, Japan.