New research shows that the sperm of men who work as painters and decorators is likely to be of poorer quality. This is due to their exposure to chemical solvents known as glycol ethers in water-based paints and other substances used in their trade.
The scientists, from the universities of Sheffield and Manchester in the UK, published their findings in the BMJ (British Medical Journals)- journal of Occupational Environmental Medicine. The researchers examined the working lives of 2,118 men across the UK in an attempt to assess how environmental work factors, particularly exposure to chemical substances, affected male fertility. The research took place in 14 fertility clinics in 11 cities across the country.
The research showed that men working with glycol ethers have a 2.5-fold increased risk of having high numbers of sperm with low motility (swimming ability) compared to men who are not often exposed to the chemicals. Sperm motility is an important factor in the fertility of men and the concentration of motile sperm per ejaculate has shown to bear direct relevance to the chances of conception. As well as this, a sperm's morphology (its size and shape) and the quality the DNA contained in it are also important factors that may be affected by chemical exposure. However, the researchers also concluded that, aside from glycol ethers, there are few other common chemical threats to male fertility in the workplace. Dr Allan Pacey, senior lecturer in Andrology at the University of Sheffield, said that 'infertile men are often concerned about whether chemicals they are exposed to in the workplace are harming their fertility', adding that 'it is reassuring to know that on the whole the risk seems to be quite low'.
The study also looked at other non-chemical factors in the men's lifestyles that may have an effect on their fertility. The researchers discovered that men who had undergone previous testicular surgery or who undertook manual work were more likely to have lower numbers of motile sperm, whereas men who drank alcohol regularly or wore boxer shorts were more likely to have better semen quality.
Dr Andy Povey, senior lecturer in Molecular Epidemiology at the University of Manchester, said that although the use of glycol ethers has declined in the past two decades, 'our results suggest that they are still a workplace hazard and that further work is needed to reduce such exposure'.