Air pollution linked to poorer quality sperm

November 22, 2017, British Medical Journal
Human sperm stained for semen quality testing in the clinical laboratory. Credit: Bobjgalindo/Wikipedia

Air pollution, particularly levels of fine particulate matter (PM2.5), is associated with poorer quality sperm, suggests research published online in Occupational & Environmental Medicine.

Although the size of the effect is relatively small in clinical terms, given how widespread is, this might spell infertility for a "significant number of couples," say the researchers.

Environmental to chemicals is thought to be a potential factor in worsening , but the jury is still out on whether air pollution might also have a role.

To explore this possibility further, the international team of researchers looked at the impact on health of short and long term exposure to (PM2.5) among nearly 6500 15 to 49 year old men in Taiwan.

The men were all taking part in a standard medical examination programme between 2001 and 2014, during which their sperm quality was assessed (total numbers, shape/size, movement) as set out by World Health Organization guidelines.

PM2.5 levels were estimated for each man's home address for a period of three months, as that is how long it takes for sperm to be generated, and for an average of 2 years, using a new mathematical approach combined with NASA satellite data.

A strong association between PM2.5 exposure and abnormal sperm shape was found. Every 5 ug/m3 increase in fine particulate matter across the 2 year average was associated with a significant drop in normal sperm shape/size of 1.29 per cent.

And it was associated with a 26 per cent heightened risk of being in the bottom 10 per cent of normal sperm size and shape, after taking account of potentially influential factors, such as smoking and drinking, age or overweight.

However, it was also associated with a significant increase in sperm numbers, possibly as a compensatory mechanism to combat the detrimental effects on and size, suggest the researchers.

Similar findings were evident after three months of exposure to PM2.5.

This is an observational study so no firm conclusions can be drawn about cause and effect, and the researchers were not privy to information on any previous fertility problems.

And exactly how air pollution could impair sperm development is not clear. But many of the components of fine particulate matter, such as heavy metals and polycyclic aromatic hydrocarbons, have been linked to sperm damage in experimental studies, the researchers point out.

Free radical damage, brought on by exposure to air pollutants, might have a possible role, as this can damage DNA and alter cellular processes in the body, they suggest.

"Although the effect estimates are small and the significance might be negligible in a clinical setting, this is an important public health challenge," emphasise the researchers.

"Given the ubiquity of exposure to air pollution, a small effect size of PM2.5 on normal morphology may result in a significant number of couples with infertility," they warn, calling for global strategies to minimise the impact of air on reproductive health.

Explore further: Air pollution exposure in early pregnancy linked to miscarriage, study suggests

More information: Xiang Qian Lao et al. Exposure to ambient fine particulate matter and semen quality in Taiwan, Occupational and Environmental Medicine (2017). DOI: 10.1136/oemed-2017-104529

Related Stories

Air pollution exposure in early pregnancy linked to miscarriage, study suggests

November 17, 2017
Exposure to common air pollutants, such as ozone and fine particles, may increase the risk of early pregnancy loss, according to a study conducted by the National Institutes of Health. The study appears in the journal Fertility ...

Huge drop in men's sperm levels confirmed by new study – here are the facts

July 27, 2017
Sperm count in men from North America, Europe, Australia and New Zealand declined by 50-60 percent between 1973 and 2011, according to a new study from the Hebrew University of Jerusalem. Surprisingly, the study, which analysed ...

Do men need sperm health supplements?

October 9, 2017
Infertility, defined as the inability of a couple to conceive after at least 12 months of regular, unprotected sex, affects about 15% of couples worldwide. Several factors can lead to infertility, but specific to men, infertility ...

What men need to know about planning a family

October 3, 2017
Having children can sometimes be a crapshoot. Some couples achieve pregnancy on the first try, while other can try for years with no success.

Sex-linked supergene controls sperm size, shape and swimming speed in birds

July 18, 2017
The size and swimming speed of sperm are controlled by a single supergene in birds, according to a new study by the University of Sheffield.

Sperm size and shape in young men affected by cannabis use

June 4, 2014
Young men who use cannabis may be putting their fertility at risk by inadvertently affecting the size and shape of their sperm according to research published today.

Recommended for you

Your heart hates air pollution. Portable filters could help

November 13, 2018
Microscopic particles floating in the air we breathe come from sources such as fossil fuel combustion, fires, cigarettes and vehicles. Known as fine particulate matter, this form of air pollution increases the risk of cardiovascular ...

Simple tips can lead to better food choices

November 13, 2018
A few easily learned tips on eating and food choice can increase amount of healthy food choices between 5 percent and 11 percent, a new Yale University study has found.

No accounting for these tastes: Artificial flavors a mystery

November 13, 2018
Six artificial flavors are being ordered out of the food supply in a dispute over their safety, but good luck to anyone who wants to know which cookies, candies or drinks they're in.

Insufficient sleep in children is associated with poor diet, obesity and more screen time

November 13, 2018
A new study conducted among more than 177,000 students suggests that insufficient sleep duration is associated with an unhealthy lifestyle profile among children and adolescents.

New exercise guidelines: Move more, sit less, start younger

November 12, 2018
Move more, sit less and get kids active as young as age 3, say new federal guidelines that stress that any amount and any type of exercise helps health.

Some activity fine for kids recovering from concussions, docs say

November 12, 2018
(HealthDay)—Children and teens who suffer a sports-related concussion should reduce, but not eliminate, physical and mental activity in the days after their injury, an American Academy of Pediatrics report says.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.