Air pollution found to damage DNA in the womb, according to research

Exposure to air pollution from diesel fumes during the second trimester of pregnancy may have a detrimental effect on the DNA of unborn children, according to a study published in the journal JAMA Pediatrics. A team of health experts at the Hasselt University in Belgium examined a total of 641 pregnant women in the country between February 2010 and December 2014 as part of the study.

The scientists assessed the mothers’ exposure to the air pollutant PM2.5 by comparing their home address against air monitoring data. Likewise, the research team also took blood samples from the placenta and umbilical cord of babies born during the study period in order to evaluate their telomere length. According to the health experts, longer telomere length equates to lower susceptibility to certain diseases.

The results have shown that babies born to mothers exposed to air pollution have significantly shorter telomeres. According to the findings, babies whose mothers got exposed to diesel fumes during the second trimester have a 9.4 percent reduction in cord telomeres. The study also revealed that every five microgram increase in PM2.5 levels during the entire pregnancy accounted to an 8.8 percent reduction in umbilical cord telomeres and 13.2 percent decrease in placenta telomeres.

“To our knowledge, this study is the first to report an association between prenatal exposure to PM2.5 air pollution and telomere length at birth, both in cord blood and placental tissue. We theorize that biological aging is associated with PM2.5 air pollution exposure, even before birth, which may underlie potential adverse health consequences later in life,” the researchers have discussed in a Daily Mail article.

“Further research is needed to determine whether these changes impact on infant health and development and to understand whether there is a ‘critical window’ during pregnancy when environmental exposures have the most detrimental effects,” says outside expert Professor Rebecca Reynolds of the Queen’s Medical Research Institute at Edinburgh University.

Diesel fumes may even change DNA within two hours

A 2015 study carried out by researchers at the University of British Columbia has revealed that exposure to diesel fumes for just two hours may already impact a person’s DNA make up. In order to conduct the study, the scientists enrolled 16 non-smoking adult volunteers with asthma who had been placed in an enclosed booth and made to breathe diluted and aged exhaust fumes. The fumes had the same air quality as that of a Beijing highway or a British Columbia port. (Related: Air pollution confirmed to have multi-generational damaging effect on future offspring.)

The research team found that being exposed to the fumes for a few hours has a detrimental effect on the chemical coating found in a person’s DNA.

“That carbon-hydrogen coating, called methylation, can silence or dampen a gene, preventing it from producing a protein – sometimes to a person’s benefit, sometimes not. Methylation is one of several mechanisms for controlling gene expression, which is the focus of a rapidly growing field of study called epigenetics,” the researchers explained.

According to the experts, air pollution exposure has caused changes in methylation at about 2,800 different points on DNA and has negatively affected about 400 genes.

Sources include:

DailyMail.co.uk

CBC.ca