- Full (HTML) - Full (PDF) - Related EHP Articles - PubMed:Related Articles - PubMed:Citation - Cited in PMC - Purchase This Issue

Guowei Pan,¹ Tomoyuki Hanaoka,^2,3,4 Mariko Yoshimura,⁵ Shujuan Zhang,¹ Ping Wang,⁵ Hiromasa Tsukino,² Koichi Inoue,⁶ Hiroyuki Nakazawa,⁶ Shoichiro Tsugane,² and Ken Takahashi³

¹Department of Environmental Epidemiology, Liaoning Provincial Center for Disease Prevention and Control, Shenyang, People's Republic of China; ²Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan; ³Department of Environmental Epidemiology, University of Occupational and Environmental Health, Kitakyushu, Japan; ⁴Department of Hygiene and Preventive Medicine, Showa University, School of Medicine, Tokyo, Japan; ⁵Department of Infectious Disease, Shenyang Municipal Center for Disease Prevention and Control, Shenyang, People's Republic of China; ⁶Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo, Japan

Abstract
Background: Observations of adverse developmental and reproductive effects in laboratory animals and wildlife have fueled increasing public concern regarding the potential for various chemicals to impair human fertility.

Objective: Our objective in this study was to assess the effect of occupational exposure to high levels of phthalate esters on the balance of gonadotropin and gonadal hormones including luteinizing hormone, follicle-stimulating hormone, free testosterone (fT) , and estradiol.

Methods: We examined urine and blood samples of 74 male workers at a factory producing unfoamed polyvinyl chloride flooring exposed to di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP) and compared them with samples from 63 male workers from a construction company, group matched for age and smoking status.

Results: Compared to the unexposed workers, the exposed workers had substantially and significantly elevated concentrations of mono-n-butyl phthalate (MBP ; 644.3 vs. 129.6 µg/g creatinine, p < 0.001) and mono-2-ethylhexyl phthalate (MEHP ; 565.7 vs. 5.7 µg/g creatinine, p < 0.001) . fT was significantly lower (8.4 vs. 9.7 µg/g creatinine, p = 0.019) in exposed workers than in unexposed workers. fT was negatively correlated to MBP (r = –0.25, p = 0.03) and MEHP (r = –0.19, p = 0.095) in the exposed worker group. Regression analyses revealed that fT decreases significantly with increasing total phthalate ester score (the sum of quartiles of MBP and MEHP ; r = –0.26, p = 0.002) .

Conclusion: We observed a modest and significant reduction of serum fT in workers with higher levels of urinary MBP and MEHP compared with unexposed workers.

Key words: di-n-butyl phthalate (DBP) , di-2-ethylhexyl phthalate (DEHP) , free testosterone (fT) , mono-n-butyl phthalate (MBP) , mono-2-ethylhexyl phthalate (MEHP) , occupational exposure. Environ Health Perspect 114:1643–1648 (2006) . doi:10.1289/ehp.9016 available via http://dx.doi.org/ doi:10.1289/ehp.9016 available via http://dx.doi.org/ [Online 27 July 2006]

Address correspondence to K. Takahashi, Department of Environmental Epidemiology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan. Telephone: 81-93-601-7401. Fax: 81-93-601-7324. E-mail: ktaka@med.uoeh-u.ac.jp

This work was supported in part by a Grant-in-Aid for Risk Analysis Research on Food and Pharmaceuticals and Cancer Research from the Ministry of Health, Labor, and Welfare of Japan.

The authors declare they have no competing financial interests.

Received 17 January 2006 ; accepted 27 July 2006.

Correction

In the the description of the MS/MS procedure for MEHP and MEHP-d4 in “Materials and Methods” of the article published online, the molecular transitions used in multiple reaction monitoring were incorrect ; they have been corrected here.