A study of more than 1,000 chemicals used in and created by fracking in the United States found that 15% were linked to reproductive and developmental health problems.
The analysis by researchers at Yale School of Public Health discovered 157 substances in fracking fluids or wastewater which were associated with reproductive or development toxicity.
Researchers were particularly concerned about 67 chemicals because they were the subject of a federal health standard or guideline.
The study, published in the Journal of Exposure Science and Environmental and Epidemiology yesterday, called for urgent research to investigate public health uncertainties.
A review of the study published today by the website Energy in Depth concluded that the authors fail to establish any credible link between fracking fluids and drinking water sources, or provide any evidence of the “possible pathways” that they alleged for exposure.
Nicole Deziel, Assistant Professor of Public Health and and author of the study, said:
“This evaluation is a first step to prioritize the vast array of potential environmental contaminants from hydraulic fracturing for future exposure and health studies.”
“Quantification of the potential exposure to these chemicals, such as by monitoring drinking water in people’s homes, is vital for understanding the public health impact of hydraulic fracturing.”
Previous studies have observed associations between proximity to fracking sites reproductive and developmental problems, the researchers said. But these studies did not investigate specific chemicals.
“This latest evaluation could inform the design of future studies by highlighting which chemicals could have the highest probability of health impact”, they said.
Consistent with other studies, the Yale research concluded:
“A greater proportion of chemicals in wastewater were linked to reproductive and developmental toxicity compared with fracturing fluids”.
“Carefully designed, rigorous exposure and epidemiologic studies are urgently needed to investigate public health uncertainties and form a scientific basis of appropriate evidence-based policies.”
The study identified 1,021 chemicals used in fracking fluids and wastewater. Of these 781 did not have information about their reproductive or development toxicity.
These chemicals “need to be rigorously analysed to determine if they pose health threats”, the researchers said.
The team analysed the remaining 240 chemicals and concluded that 157, including arsenic, benzene, cadmium, lead, formaldehyde, chlorine and mercury, were associated with either development or reproductive toxicity or both.
The lead author, Elise Elliott, a public health doctoral student, said:
“We focused on reproductive and developmental toxicity because these effects may be early indicators of environmental hazards. Gaps in our knowledge highlight the need to improve our understanding of the potential adverse effects associated with these compounds”.
A systematic evaluation of chemicals in hydraulic-fracturing ﬂuids and wastewater for reproductive and developmental toxicity. Elise G. Elliott, Adrienne S. Ettinger, Brian P. Leaderer, Michael B. Bracken and Nicole C. Dezie in Journal of Exposure Science and Environmental and Epidemiology, 6th January 2016
For a rebuttal of the research see: Study alleges harm from fracking chemicals with zero evidence by Energy in Depth