Scientists: air pollution can cause infertility in men

© Fotolia / opersonliga couple in the bedroomScientists: air pollution can cause infertility in men© Fotolia / oneinchpunch

. High levels of air pollution may affect the quality of sperm in men, which could significantly increase the likelihood of infertility and reducing the birth rate in countries with a poor environment, according to an article published in the journal of Occupational and Environmental Medicine.

«By itself, this effect is quite small from a clinical point of view, but, nevertheless, it represents an important threat to the health of the nation. Given that the air is contaminated in almost all the regions of human habitation, even the faint influence of pollutants on the shape of the sperm may produce a large number of infertile couples,» write the Blue Qian Liao (Xiang Qian Lao) from the Chinese University of Hong Kong (China) and his colleagues.

According to current estimates, about 10-15% of couples in Western countries are not able to procreate due to infertility of one of the two «halves». Contrary to common perceptions, the share of infertile men and women is approximately equal, with most of the infertile men and women lose fertility at the age of 40-55 years. Biological causes infertility in most cases remain unknown because of the complexity and poor knowledge of those genetic mechanisms that control the production of eggs and sperm.

In recent years, the incidence of infertility in developed countries of the West and Asia has grown significantly, which scientists have linked with many social and natural factors, including a marked deterioration of the environment.

Liao and his colleagues have found the first unequivocal evidence that the epidemic of infertility and the deterioration of the environment can be really related to each other, examined data collected by hospitals in Taiwan, in monitoring the health of about 6.5 thousands of men over the past 15 years.

These medical information, according to the researchers, included data on the quality and viability of their sperm, for the first time allowed the researchers to assess how the level of air pollution in the area of the island, where lived the participants of these surveys for at least 2-3 years, had an influence on their reproductive abilities.

As it turned out, the concentration of harmful aerosols in the air quite weakly, but affect two important properties of sperm and seminal fluid form male germ cells and their mobility, as well as its consistency. As a rule, the increase in mass of these particles of 5 micrograms per cubic meter of air has worsened the quality of sperm by 1.29%, but it made it more dense in both the long and short terms.

Such changes, as the researchers note, negatively affected the General level of fertility of men who lived in areas with high levels of air pollution, causing the proportion of men suffering from infertility or problems with conception, was in these parts of Taiwan are much higher than the average for the island.

Similar issues, the opinion of Chinese doctors, may be typical for residents of other countries with developed industry emitted into the atmosphere large amounts of aerosols and toxic chemicals. This phenomenon, therefore, can be one of the reasons why fertility has declined markedly in many States in recent years, despite all the efforts of their governments to raise this figure.