Can air pollution affect your ability to reproduce? There is increasing investigation into how pollution affects fertility. According to a study, the incidence of infertility has been increasing in industrial countries from 7% - 8% in 1960 to 20% - 35% today. The World Health Organization (WHO) estimates that approximately 15 percent of the global population has difficulty with fertility, and male infertility accounts for about half of those problems.
Going Up in Smoke
In 2017, a study suggested that “modern life” was to blame for a 60 per cent drop in sperm counts in several countries in just about four decades!
The largest study to investigate the effects of fine particulate matter pollutants on health focused on semen quality. The results of the study suggest that a “significant number of couples” could suffer from infertility resulting from air pollution. To investigate this possibility, researchers took the sperm quality data from 6,500 15- to 49-year old men in Taiwan, and matched it against the fine particulate levels at their home addresses. They found a strong association between high air-pollution levels and abnormal sperm shape. The effects were relatively small, but given the prevalence of air pollution the researchers note that even small changes resulting from it could present a major public health challenge.
Professor Allan Pacey, an andrologist at the University of Sheffield says,
“I have seen this study, and several others. And I hold a strong opinion that pollution does negatively impact male reproductive health.”
Environmental and life style factors are possible contributors to changes in male reproductive health, in particular, continuous exposure to environmental endocrine disrupting chemicals. The male reproductive system malfunction seems to be a good sensitive marker of environmental hazards. Dr Himanshu Chadha, a Chandigarh-based sexologist says,
“When we breathe in an area with high levels of air pollution, fine particulates containing toxic chemicals such as heavy metals pass into our lungs, allowing them to enter the bloodstream. From there, they can cause damage to semen, something that has been demonstrated in laboratory studies.”
The mechanisms through which pollutants affect men's infertility may be hidden behind a smokescreen, but experts agree that pollutants are capable of accumulating in body fluids such as blood, urine, and seminal fluid.
What Happens to the Sperm in Bad Air
Exposure to air pollution has been linked to alterations in sperm parameters. For example, the Taiwan study assessed sperm quality and measured the level of fine particulate pollution, which is caused by cars, dust from construction and wood burning, around participants’ homes. It was associated with a heightened risk of being in the bottom 10% of normal sperm size and shape, after taking account of potential factors, such as smoking and drinking, age and weight. The report, published in the journal Occupational & Environmental Medicine, said that although the effect is “relatively small in clinical terms” it might still lead to infertility for a “significant number of couples” given the extent of air pollution in cities around the world. The study concluded that there was "a robust association between exposure to PM2.5 air pollution and low percentage of sperm normal morphology in reproductive-age men."
“Air pollution is usually associated with increased air content of carbon monoxide (CO), nitrous dioxide (NO2), sulfur dioxide (SO2), ozone, lead (Pb), and particulate matter. Particulate Matter (PM) in the respirable range (PM 2.5) is of particular interest, because it can carry multiple trace elements and Polycyclic Aromatic Hydrocarbons (PAHs), a group of compounds that include several endocrine disruptors. Endocrine disruptors can affect both the hypothalamic-pituitary axis and testicular spermatogenesis and have the potential for causing sperm alterations.”Dr Himanshu Chadha
To put it simply, bad air can affect the shape and size of sperm and its quality.
Dr Richard Shaw, an expert in male reproductive health, based in Sheffield adds to this,
“The presence of lead and cadmium in particulate matter has a direct impact on hormone concentration, male infertility, and sperm parameters. Geographic differences in the amount of naturally occurring cadmium have been correlated with the rate of prostate cancer.”
He adds that some studies have suggested that environmental toxins alter the sperm’s DNA integrity. “Young and middle-aged men are more affected by air pollution and the possibility of damage to sperm in this age will be higher.”
These dramatic changes in fertility are very important and should be treated with great caution.
Scientists may not be convinced that this is the final word on air pollution and male fertility, but awareness and more research findings can change the attitude of infertile men who live in cities with high air pollution.