Hum. Reprod. Advance Access published online on February 6, 2009
Human Reproduction, doi:10.1093/humrep/dep006
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Urinary metabolites of polycyclic aromatic hydrocarbons in relation to idiopathic male infertility
1 Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, 140 Hanzhong Road, Nanjing 210029, People's Republic of China 2 National Center for STD Control, Chinese Academy of Medical Sciences and Peking Union Medical College Institute of Dermatology, Nanjing, People's Republic of China 3 Huai’an First Affiliated Hospital of Nanjing Medical University, Huai’an, People's Republic of China 4 Center of Hygienic Analysis and Detection, School of Public Health, Nanjing Medical University, Nanjing, People's Republic of China
5 Correspondence address. Tel: +86-25-86862863; Fax: +86-25-86662863; E-mail: xrwang{at}njmu.edu.cn
BACKGROUND: Limited studies have suggested that male reproductive function might be associated with exposure to polycyclic aromatic hydrocarbons (PAHs).
METHODS: Five hundred and thirteen idiopathic infertile male subjects and 273 fertile males as controls were recruited in this study, through eligibility screening procedures. Individual exposures to PAHs were measured as spot urinary concentrations of four PAH metabolites, including 1-hydroxynaphthalene (1-N), 2-hydroxynaphthalene (2-N), 1-hydroxypyrene (1-OHP) and 2-hydroxyfluorene (2-OHF), which were adjusted by urinary creatinine (CR). Subjects with idiopathic infertility were further divided into ‘normal’ and ‘abnormal’ semen quality groups based on their semen volume, sperm concentration, sperm number per ejaculum and sperm motility.
RESULTS: The median CR-adjusted urinary concentrations of 1-N, 2-N, 1-OHP, 2-OHF and Sum PAH metabolites (sum of all four metabolites) of control group were lower than those found in case groups. Subjects with higher urinary concentrations of 1-OHP, 2-OHF and Sum PAH metabolites (assessed as tertiles) were more likely to have idiopathic male infertility (P-value for trend = 0.034, 0.022 and 0.022, respectively). Comparing the two groups of idiopathic infertile subjects with different semen quality, a higher idiopathic infertility risk was found in the group with abnormal semen quality.
CONCLUSIONS: Increased urinary concentrations of 1-OHP, 2-OHF and Sum PAH metabolites were associated with increased male idiopathic infertility risks, while the idiopathic infertile subjects with abnormal semen might be at higher risk.
Key words: polycyclic aromatic hydrocarbons/metabolite/human urine/male infertility/semen quality
Submitted on September 20, 2008; resubmitted on November 28, 2008; accepted on January 5, 2009.