Cadmium, found in cigarettes, causes male infertility: Study

According to the study, conducted in assistance with the Department of Environmental Sciences of Bharathiar University, the infertility rate among young professionals was on the rise in the Western Districts of Tamil Nadu, since more than 1,000 Foundry units were producing over 40,000 tonnes of casting every month in the region.

The accumulation of metals such as cadmium, lead, chromium and nickel in the blood and semen of 62 ‘infertile’ men were studied in detail for the research, Kannagi said.

The semen samples of these infertile men, in the age group of 25-40, whose professions ranged from white collar jobs to agriculture, living in the districts of Coimbatore, Erode and Tirupur were analysed for heavy metals. Alongside, samples of 75 fertile men were also taken up for comparison, she said.

The study could be a wake up call for the industrial belts, which clearly showed that infertile men had significantly higher deposits of Cadmium in their blood samples.

The infertile had higher cadmium levels, which could be a pointer to the “link between industrial pollution and infertility among men,” Kanngi said.

The key sources of cadmium were industrial effluents, especially released from foundries and cigarette smoke. While fertile men had a cadmium deposit to a maxium extent of 1.65 micrograms per ML, the infertile men had double the load of cadmium with accumulation as high as 3.14 micrograms per ml, the study said.

As only 22 of the 62 infertile men taken up for study were smokers, it was clear that majority of them had absorbed the cadmium only through industrial pollution.

Men’s fertility potential was tested by sperm count, its motility and shape. As per the WHO standards the sperm count should be over 20 million per ml and the overall motility should be over 50 per cent, Kannagi said.

A normal sperm should be able to swim up to the egg in the fallopian tube and fertilise it by actively drilling through the layers around the egg called the ‘zona pellucida.’

A good sperm would have a normal oval head with a long tail and a sample should have at least 30 per cent normal looking sperms, she said.

The sperm count of the infertile in the study group ranged between 24.33 and 15.27 million per ml, which was not significantly low. However, more than the sperm count, it was the movement of the sperms, their ability to swim across the egg and fetilise it, which was important, she said.

The infertile under study had as low as 1.03 per cent of Grade A sperms which swam faster with lateral head movement, while grade B were slow.

The study was a clear pointer that metal accumulation could significantly alter the motility of sperms and the sorry spin-off could be a long, hopeless wait for men to become fathers, Kannagi said.