The Effects of Nonylphenol on Semen Quality in Males: A Pilot StudyLu, C Y.*; Chang, C H.†; Lin, R S.*; Hung, Y C.†; Torng, P L.*; Chen, S U.*; Sung, F C.†Epidemiology: November 2006 - Volume 17 - Issue 6 - p S396 ISEE/ISEA 2006 Conference Abstracts Supplement: Poster Abstracts: Abstracts Author Information Article Outline *National Taiwan University, Taipei. †China Medical University, Taichung. Purpose: Methods: Results: Conclusion: P-419 Back to Top | Article Outline Purpose: Nonylphenol (NP), the final biodegradation product of surfactants Nonylphenol polyethoxylates (NPEs), shows weak estrogenic effect in vitro and in vivo studies. This study investigated the adverse effects of NP exposure, using urinary 4-nonylphenol (4-NP) as a biomarker, on the reproductive health in men. Back to Top | Article Outline Methods: With informed consents, urine samples after 8-hour fasting and semen specimen were collected for urinary 4-NP determination and the sperm exam respectively from 38 men with complain of male infertility at the infecundity clinic of a medical center, northern Taiwan. Each participant completed a self-reported questionnaire for information on socio-demographic characteristics and life styles. Back to Top | Article Outline Results: The results showed that the sperm concentration of semen was significantly associated with the urinary 4-NP level. The average log urinary 4-NP level for men with sperm densities of less than 20×106 1/ml was higher than that for men with sperm densities greater than 20×106 1/ml (1.53 vs. 1.19 μg/g creatinine, respectively). The multivariate logistic regression analysis showed that men with the NP level greater than the overall median level, 1.29 μg/g creatinine, had a high risk of having sperm densities of less than 20×106 1/ml (odds ratio = 21.0, 95% confidence interval = 1.19–370). Back to Top | Article Outline Conclusion: This study demonstrates that there was an observed association between decreased semen quality and NP levels.Keywords: 4-nonylphenol; infecundity; sperm densities; multivariate logistic regression; infertility © 2006 Lippincott Williams & Wilkins, Inc.