THE UK government has approved fracking in certain areas, including large parts of Scotland, as many believe the extraction of gas from shale will help countries reap economic benefits.
But this hope also comes with an ecological and societal price. There is a growing concern that the serious and dirty downside to fracking needs to be addressed more diligently before the governments embrace a large-scale expansion of extracting natural gas from shale.
During the drilling process, flowback water, laced with toxic chemicals, comes back up to the surface along with the gas.
Disposal of this toxic brew should be of concern to all of us, not just those living in close proximity to the drilling rig, because of the potential for harm to the environment as well as to human and animal health. And, there is the “methane issue”.
Natural gas is mostly methane, a potent greenhouse gas, which raises concerns about contributing to climate change.
Given that huge amounts of water are used in the drilling process, it is not unrealistic that an unintended consequence may be diminishing water levels in some local aquifers. Air quality has been shown to be adversely affected partly because fumes containing benzene, toluene, and xylene are released, each potentially toxic petroleum hydrocarbons. Lorry traffic to and from drilling sites contributes to air pollution.
The natural gas industry asserts that these concerns are not founded. If so, then why is the industry balking at having empirical health impact assessment studies conducted?
The lack of scientific evidence looking at the public health impact of natural gas extraction complicates the issue.
There are a host of questions and concerns that the industry and policy makers need to address in order to fully assess the potential for harm from hydraulic fracturing.
Clearly, there is a need to know much more about the chemicals used during shale gas extraction. There needs to be well-designed epidemiologic studies upon which policy recommendations should be made. The burden of proof for potentially harmful actions should rest on the assurance of safety in areas of scientific uncertainty.
• Dr Madelon Finkel is Professor of Clinical Public Health and Director, Office of Global Health Education at Weill Cornell Medical College, New York.