title: Endocrine disruptive effects of chemicals eluted from nitrile-butadiene rubber gloves using reporter gene assay systems.
abstract: Disposable gloves made of nitrile-butadiene rubber (NBR) are used for contact with foodstuffs rather than polyvinyl chloride gloves containing di(2-ethylhexyl)phthalate (DEHP), because endocrine-disruptive effects are suspected for phthalate diesters including DEHP. However, 4,4'-butylidenebis(6-t-butyl-m-cresol) (BBBC), 2,4-di-t-butylphenol, and 2,2,4-trimetyl-1,3-pentanediol diisobutyrate can be eluted from NBR gloves, and possibly also detected in food. In this study, we examined the endocrine-disrupting effects of these chemicals via androgen receptor (AR) and estrogen receptor (ER)-mediated pathways using stably transfected reporter gene cell lines expressing AR (AR-EcoScreen system) and ER (MVLN cells), respectively. We also examined the binding activities of these chemicals to AR and ER. The IC50 value of BBBC for antagonistic androgen was in the range of 10(-6)M. The strength of inhibition was about 5 times that of a known androgen antagonist, 1,1'-(2,2-dichloroethylidene)bis[4-chlorobenzene] (p,p'-DDE), and similar to that of bisphenol A. The IC50 value of BBBC for antagonistic estrogen was in the range of 10(-6)M. These results suggest that BBBC and its structural homologue, 4,4'-thiobis(6-t-butyl-m-cresol) are androgen and estrogen antagonists. It is therefore necessary to study these chemicals in vivo, and clarify their effect on the endocrine system.
authors.affiliation: Department of Environmental Health and Toxicology, Tokyo Metropolitan Institute of Public Health, 3-24-1Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan. Kanako_Satou@member.metro.tokyo.jp
authors.forename: Kanako
authors.initials: K
authors.lastname: Satoh
authors.forename: Ryouichi
authors.initials: R
authors.lastname: Nonaka
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Ohyama
authors.forename: Fumiko
authors.initials: F
authors.lastname: Nagai
authors.forename: Akio
authors.initials: A
authors.lastname: Ogata
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Iida
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D001681:Biological Assay / Q000379:methods; D002070:Butadienes / Q000737:chemistry*; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D020724:Elastomers / Q000737:chemistry*; D052244:Endocrine Disruptors / Q000737:chemistry / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects*; D017930:Genes, Reporter; D017575:Gloves, Protective / Q000592:standards*; D015394:Molecular Structure; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism
chemical_list: D002070:Butadienes; D020724:Elastomers; D052244:Endocrine Disruptors; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; C086285:nitrile butyl rubber