ABSTRACT
Objective: To study the effect of exposure to vehicle emissions on male fertility
Patients and Methods: 102 patients were enrolled in the study. They were divided into three groups; group I [n = 13] were mainly from rural areas minimally exposed to environmental urban vehicle emissions, group II [n = 20] composed of indoor workers who are incidentally exposed to risk and group III [n = 69] were occupationally exposed to environmental air pollution. A full questionnaire including socioeconomic data, histories of exposure to pollution, reproductive histories were taken. Cases with overt or questioned infertility were excluded. Two groups of investigations were done; the first included biomarkers of vehicle emission pollution, namely, carboxyhemoglobin in the peripheral blood, sulphur and sulphur dioxide in urine and lead in blood and semen. The second group of investigations was targeted towards the fertility indices including reproductive hormones and semen characteristics
Results: The level of blood carboxyhemoglobin and semen lead were remarkably higher in the exposed group compared to other groups. There were statistically significant decrease in fertility indices [serum testosterone, semen count, motility and sperm morphology] in the highly exposed group III. Blood lead was negatively correlated with serum testosterone [r = - 0.498, p<0.001] and also negatively correlated with semen count and motility [r = - 0.617, p<0.001; r = - 0.537, p<0.001, respectively]. Abnormal sperm morphology was positively correlated with both blood and semen lead [I = 0.347, p<0.001; r=0.296, p<0.05, respectively]. Carboxyhemoglobin level showed a significant negative correlation with both sperm count and motility [r = 0.219, p<0.05; r= 0.308, p<0.05, respectively]. Sulphur dioxide level in urine showed insignificant correlation with reproductive hormones and seminal indices [p>0.05]
Conclusion: The exposed group [group III] showed deterioration and decline in some essential fertility indices and the deterioration is correlated to biomarkers of vehicle induced air pollution