Studies show that EDCs disrupt normal sex-hormone function in humans.

A new study has found high levels of chemicals known as endocrine-disrupting chemicals (EDCs) in water samples obtained at sites in the state of Colorado where hydraulic fracturing (fracking) is used to extract oil and gas.

Previous studies have shown that EDCs disrupt normal sex-hormone function in humans. They have been linked to cancer, infertility and disruption of normal reproductive function in men and women, birth defects, impaired immune and neural function, and several other health problems in humans. Researchers have found that fetuses, infants and young children exposed to EDCs have a higher risk of illnesses related to endocrine malfunction.

According to the study published recently by the journal Endocrinology, high levels of EDCs were found in surface and groundwater samples collected in Colorado's Garfield County, a major oil and gas development area with over 10,000 wells where fracking is practiced.

The researchers collected water samples at five fracking sites in Garfield County where spills were known to have occurred in the last six years. They tested the samples for different types of EDCs and found that, "Of the 39 unique water samples, 89 percent, 41 percent, 12 percent, and 46 percent exhibited estrogenic, anti-estrogenic, androgenic, and anti-androgenic activities, respectively.”

The study found that water samples collected from the Colorado River also had significantly high levels of EDCs.

The Colorado River, being the major drainage basin in the region, receives fracking wastewater spills occurring at natural gas wells in the region. Significantly, the researchers found that water collected from sites with low or no fracking activity in Garfield County and Missouri had much lower levels of EDCs. The Los Angeles Times reports that Susan Nagel, an endocrinologist at the University of Missouri School of Medicine and lead author of the study, said, "With fracking on the rise, populations may face greater health risks from increased endocrine-disrupting chemical exposure."

This is not the first time that researchers have raised concern about chemicals used in fracking known or suspected to be EDCs. According to the Los Angeles Times, researchers have identified about 100 such chemicals used in fracking.