Exposure to particulate air pollution has now been linked to reduced sperm production in mice. This prompts the question, is air pollution leading to an increase in infertility?
The exposure to tiny air pollution particles was linked to a reduction in sperm production by mice by the Endocrine Society.
Can air pollution cause infertility?
The World Health Organization (WHO) estimates that approximately 15 percent of the global population has difficulty with fertility, of which about 50 percent of those difficulties are accounted for by male infertility.
The lead researcher on this study, Elaine Maria Frade Costa, M.D., Ph.D., of Sao Paulo University in Sao Paulo, Brazil, commented: “Infertility rates are increasing around the world, and air pollution may be one of the main factors.”
The study investigated the effect of particulate matter on sperm production. Particulate matter is a mixture of solid particles and liquid droplets which are found in the air.
PM2.5 is ta fine inhalable particle, the biggest of which is still around 30 times smaller than the average human hair. PM2.5 is known to disrupt the endocrine system, which is involved in reproduction including the production of sperm, in humans and animals.
Linking PM2.5 exposure and the reduction in sperm production
The exposure to PM2.5 led to changes in the levels of genes related to testicular cell function. The exposure to PM2.5 after birth seemed to be the most harmful to testicular function.
Costa explained that these changes are epigenetic, which means they are not caused by changes in DNA sequence, and can determine which proteins a gene expresses.
The study is the first to demonstrate exposure to air pollution of a large city impairs the production of sperm through epigenetic modifications, mainly in exposure after birth. Costa added: “These findings provide more evidence that governments need to implement public policies to control air pollution in big cities.”