Study links fracking wells to increased asthma attacks

Asthma patients were 1.5 to four times more likely to have asthma attacks if they lived near bigger or a larger number of unconventional natural gas development wells, according to a study published on Monday in the Journal of the American Medical Association Internal Medicine.

The research was conducted jointly by scientists at the Johns Hopkins University and Geisinger Health System using electronic health records from 2005 to 2012 in north and central Pennsylvania.

Of the 27,000 identified asthma cases with patients' age ranging from 5 to 90 that met the study's criteria, about 20,000 were categorised by the researchers as having mild attacks (new oral corticosteroid orders), 1,800 were moderate attacks (emergency room visits), and 4,700 suffered from severe attacks (hospitalisations).

Rapid unconventional natural gas development had been undertaken in Pennsylvania in recent years with over than 6,200 wells being drilled from the mid-2000s to 2012. The study researchers assigned each well metrics on the basis of location, depth, number, developmental phases and production volume and length data obtained from state departments.

They proceeded to map out the wells and the location of the asthma patients and compared them with patients who did not report asthma attacks in the same year.

The study found that patients who lived close to more or bigger natural gas wells ran higher risks for  asthma attacks across all four stages of development: well pad preparation, well drilling, stimulation (the stage commonly referred to as fracking) and production. Asthma patients who lived near wells that were in the production phase, which could last for years, were at greater risk.

According to proponents of fracking, it had the potential to be greener, in terms of carbon footprint, than some other energy sources.

However, critics worry about the impact on humans and the environment namely, air and water pollution, earth tremors and potential health risks.

According to Public Health England which looked at the issue in the UK "the risks to public health from exposure to emissions from shale gas extraction are low if operations are properly run and regulated".