title: Effects of n-butylparaben on steroidogenesis and spermatogenesis through changed E₂ levels in male rat offspring.
abstract: Parabens are widely used as antibacterial agents, which are concerned recently in the relationship between the use of parabens and reproductive toxicity. So that reassessment of the risk of parabens is needed. In this study, one of parabens, n-butylparaben (n-BP) was orally administered to pregnant Wistar rats (0, 64, 160, 400 and 1000 mg/kg/day) from gestation day (GD) 7 through postnatal day (PND) 21. Reduced anogenital distance (AGD) and delayed preputial separation (PPS) were observed in the male offspring. The weights of the testes were significantly reduced at PND 21-90. The weights of the epididymides were significantly reduced at all monitoring points, except PND 35. Seminal vesicle weights were significantly reduced on PND 21. Serum testosterone (T) was significantly decreased, especially on PND 49. The levels of 17β-estradiol (E2) showed an increase at each of the tested points except on PND 180. Serum luteinising hormone (LH) and follicle-stimulating hormone (FSH) levels in the n-BP treated groups were lower on PND 21, 35 and 49 but elevated on PND 90 compared to control levels. n-BP reduced epididymal cauda sperm counts and daily sperm production in a dose-dependent manner; this difference was statistically significant at exposure groups of 400 and 1000 mg/kg/day. The present study strongly suggests that exposure to n-BP in utero and during lactation has adverse effects on the reproductive system in male offspring, with a no observed adverse effect level (NOAEL) of 160 mg/kg/day. To our knowledge, this is the first study that reports increased E2 levels of male rats following n-BP exposure; we suggest that E2 levels may be considered as biomarkers for some endocrine disrupting chemicals (EDCs).
authors.affiliation: Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, No. 29 Nanwei Road, Xicheng District, Beijing 100050, China. Electronic address: jessica242@sina.com.
authors.forename: Linyuan
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, No. 7 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. Electronic address: lizi1214@sina.com.
authors.forename: Li
authors.initials: L
authors.lastname: Dong
authors.affiliation: Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, No. 29 Nanwei Road, Xicheng District, Beijing 100050, China. Electronic address: dsj1348@126.com.
authors.forename: Sijin
authors.initials: S
authors.lastname: Ding
authors.affiliation: Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, No. 29 Nanwei Road, Xicheng District, Beijing 100050, China. Electronic address: qiaopeihuan@aliyun.com.
authors.forename: Peihuan
authors.initials: P
authors.lastname: Qiao
authors.affiliation: Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, No. 7 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. Electronic address: wangchongfly@163.com.
authors.forename: Chong
authors.initials: C
authors.lastname: Wang
authors.affiliation: Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, No. 7 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. Electronic address: zhangming2550@163.com.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, No. 7 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. Electronic address: xia007123@sina.com.
authors.forename: Lixia
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, No. 29 Nanwei Road, Xicheng District, Beijing 100050, China. Electronic address: 1329272221@qq.com.
authors.forename: Qingcheng
authors.initials: Q
authors.lastname: Du
authors.affiliation: Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, No. 7 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. Electronic address: yiminli@sina.com.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, No. 7 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. Electronic address: ningtanglcp@126.com.
authors.forename: Ning
authors.initials: N
authors.lastname: Tang
authors.affiliation: Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, No. 29 Nanwei Road, Xicheng District, Beijing 100050, China. Electronic address: bjchangbing@sohu.com.
authors.forename: Bing
authors.initials: B
authors.lastname: Chang
mesh_terms: D000818:Animals; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008431:Maternal-Fetal Exchange; D009929:Organ Size / Q000187:drug effects; D010226:Parabens / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D017208:Rats, Wistar; D013076:Sperm Count; D013091:Spermatogenesis / Q000187:drug effects; D013737:Testis / Q000187:drug effects* / Q000473:pathology; D013739:Testosterone / Q000097:blood
chemical_list: D010226:Parabens; C038091:butylparaben; D013739:Testosterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone
keywords: Endocrine disrupting chemicals; Oestrogene; Parabens; Reproduction; Testosterone