Résumé
Cadmium is a new class of endocrine disruptors with a wide range of effects on mammalian reproduction. To determine the association between occupational exposure to cadmium and male fertility. Blood cadmium and lead levels were estimated by atomic absorption spectrophotometry in 30 infertile male welders and 30 healthy age matched, fertile, male welders as controls. FSH, LH and testosterone were estimated and semen analysis was done. The age ranged between 27-45 years. The infertile welders show significantly higher blood cadmium levels [42.7 +/- 1.7 micro g/dl] compared to the fertile group [11.3 +/- 4.1 micro g/dl, p <0.01] while serum testosterone and FSH are significantly lower among the infertile welders compared to controls [p < 0.05]. In addition, blood cadmium but not blood lead level has a significant inverse correlation, with serum testosterone and FSH [r=-0.37, -0.39, respectively, p < 0.05]. Oligozoospermia and abnormal forms is present in 56.7% and 43.3% of the infertile welders, respectively. Smokers have significantly higher blood cadmium compared to non smokers [p <0.01]. Smoking index has insignificant correlation with FSH, LH and testosterone but shows a significant positive correlation with blood cadmium [p <0.05] but not blood lead level. Blood cadmium is an independent predictor of infertility among the studied population Chronic exposure to cadmium can affect endocrine function of reproduction in males at the level of hypothalamus, pituitary and the testes together with its effects on spermatogenesis. Smoking can potentiate the effects of cadmium on the male reproductive system