The effects of Pb on sperm parameters and sperm DNA fragmentation of men investigated for infertility

Background Lead (Pb) is one of the metals most prevalent in the environment and is known to cause infertility and deoxyribonucleic acid (DNA) fragmentation. This study aimed to determine the association between seminal plasma Pb and sperm DNA fragmentation in men investigated for infertility. Methods Male partners (n = 300) of couples investigated for infertility were recruited after informed consent was obtained. Sperm parameters were assessed according to the World Health Organization (WHO) guidelines. Seminal plasma Pb was estimated by atomic absorption spectrophotometry after digestion with nitric acid. Results In Pb-positive and -negative groups the sperm parameters and sperm DNA fragmentation were compared using independent sample t-test and the Mann-Whitney U-test, respectively. The mean [standard deviation (SD)] age and duration of infertility were 34.8 (5.34) years and 45.7 (35.09) months, respectively, and the mean Pb concentration was 15.7 μg/dL. In Pb positives compared to Pb negatives the means (SD) of sperm count, progressive motility viability and normal morphology were lower (p > 0.05) but the DNA fragmentation was significantly higher 39.80% (25.08) than Pb negatives 22.65% (11.30). Seminal plasma Pb concentration and sperm DNA fragmentation had a positive correlation (r = 0.38, p = 0.03). A negative correlation was observed between sperm DNA fragmentation and sperm concentration, progressive motility, total motility and viability. When the DNA fragmentation was ≥30% sperm concentration and viability decreased (p < 0.05). Conclusions Pb in seminal plasma had a significant effect on sperm DNA fragmentation but not with other sperm parameters.