Male pattern baldness, which develops gradually, typically starting with the appearance of a bald spot in the crown and thinning of the temples, is known to be hereditary.

But a team of researchers at the University of London has linked the onset of male pattern baldness to environmental factors like air pollution and smoking, British newspaper the 'Daily Mail' reported today.

According to the study, the toxins and carcinogens which are found in polluted air can actually stop hair growing by blocking mechanisms that produce the protein from which the hair is made.

"We think any pollutant that can get into the bloodstream or into the skin and into the hair follicle could cause some stress to it and impair the ability of the hair to make a fibre.