Children born near oil and gas extraction facilities may face a higher risk of developing congenital heart defects. This is revealed by a study conducted by the Colorado School of Public Health, which analysed a sample of 3,324 children born in Colorado between 2005 and 2011. According to the researchers, the likelihood of giving birth to a child affected by a congenital heart defect would be 40–70 per cent higher for mothers living in regions where extraction activity is particularly intense.

The research, published in Environment International and conducted by Dr Lisa McKenzie, analysed the rate of congenital heart defects (CHD) in children born in an area — such as Colorado — where oil and gas extraction activity is particularly intense (the state is home to approximately 60,000 fracking facilities). "We recorded a higher incidence of congenital heart defects in children born in areas where extraction activity is very intense," the researcher explained.

CHDs are structural abnormalities of the heart or the great blood vessels, and represent the most common type of congenital malformation and a significant cause of infant mortality. The newly published study estimated the intensity of oil and gas extraction activity (drilling, well completion and extraction proper) across different areas of Colorado, and followed over 3,000 mothers from three months before conception to the second month of pregnancy — the gestational period during which the development of the foetal cardiac system takes place. The study's data showed higher rates of CHD in rural areas with high levels of extraction activity. The researchers ruled out the absence of other significant air pollutants that could have contributed to the increase in congenital malformations, thereby influencing the survey's results.

Congenital heart defects and fossil fuels: this is not the first study

This is not the first time a scientific study has linked foetal and neonatal health with pollution associated with oil and gas extraction. A previous study had examined 124,842 births that took place in rural Colorado between 1996 and 2009, likewise finding an increase in congenital heart defects correlated with the density of oil and gas wells around the mother's place of residence. Another study in Oklahoma, conducted on 476,000 newborns, had in turn found a link between proximity to oil and gas wells and various types of CHD (without, however, arriving at more precise data).

At least 17 million people in the United States alone and 6 per cent of Colorado's population live less than a mile from an oil and gas extraction site.