In Glenwood Springs, Colorado, mothers have been suffering from an unusually high rate of miscarriage and stillbirths.

A newly published study has concluded that 70% of cases lived greater than 15 miles from an active well created as a result of fracking and directional drilling. The remaining 30% were between 5 to 8 miles from the nearest active well.

This link is not a coincidence. A major review study undertaken by Susan C. Nagel and colleagues at the University of Missouri emphasises the major health threat posed by fracking and other unconventional oil and natural gas operations (UOGs) - especially to pregnant women and would-be parents.

"UOG operations release large amounts of reproductive, immunological, and neurological toxicants, carcinogens as well as endocrine disrupting chemicals (EDCs) into the environment that may negatively affect human health", the study warns.

The conclusion is clear: unconventional oil and natural gas operations pose a serious threat not only to the environment, but to our health and ability to have children.

"The studies show that humans can be harmed by these chemicals released from fracking", Nagel said in an interview. "There is strong evidence of decreased semen quality in men, higher miscarriages in women and increased risk of birth defects in children."

Fracking: releasing chemicals in air and water near operations

Hundreds of chemicals have been associated with processes of fracking. Nagel's most recent report has found that volatile organic compounds (VOC's) such as benzene and toluene, as well as heavy metals such as lead and arsenic are directly linked with fracking processes.

More than 750 chemicals are injected into the ground under high pressure, the returned waste of these fluids not only contains the chemicals that are harmful in themselves, but also radioactive materials that have been liberated from the shale layer. The traditional treatment of this wastewater does not remove these chemicals that have escaped from their natural location.

This wastewater is then disposed of in landfills, evaporation pits, as well as being sprayed onto roads to reduce dust and melt ice. These practices directly and indirectly contaminate surface and ground water.

The common spills, leaks and discharges of UOG wastewater entail that those 15 million Americans that live within one mile of directional drilling and hydraulic fracturing are directly at risk, potentially coming into contact with those chemicals that Nagel links to adverse reproductive outcomes.

UOG processes also contribute to the concentration of numerous contaminants into the air, which can be inhaled in the air near operations.

Reproductive disorders - sperm counts down, miscarriages up



More than 130 fracturing chemicals have been identified as known or potential EDCs, while many others remain unassessed:

"Volatile organic compounds and heavy metals are just a few of

the known contributors to reduced air and water quality that pose a threat to human developmental and reproductive health. The developing fetus is particularly sensitive to environmental factors, which include air and water pollution."

The effects of exposure to EDCs are well documented, affecting reproductive organs, body weight, puberty and fertility. Fertility declines are also linked to fracking chemicals such as BTEX, xylene and benzene. Workers exposed to these chemicals have suffered from low sperm count and negative sperm quality.

Back to Colorado, the exposure of pregnant women to heavy metals increases the risk of miscarriage. During fracking, heavy metals such as lead and cadmium are routinely mobilised and have been shown to contaminate surface and ground water.

Meanwhile high exposure to benzene and toluene, both used and produced by UOG operations, have led to women having three to five times the miscarriage rate of those with low exposure.

Whilst the Colorado Department of Public Health and the Environment concluded that no single environmental factor could explain the anomalies of miscarriage rates in Glenwood Springs, the majority of women were from the Piceance Shale Basin, a densely - drilled UOG region.

The Ecologist explored previously the negative consequences of coming into contact with 'gender-bender' endocrine disrupting chemicals (EDCs), which bind to endogenous hormone receptors in order to either activate or repress a typical result.

Other toxic impacts on reproduction

A correlation between benzene and toluene, which are both heavily involved with the processes of fracking, and effects on women's menstrual cycle has been discovered when looking at petrochemical workers in Beijing. Inability and difficulty to conceive as well as premature menopause is also linked to exposure to toluene.

Preterm birth is the leading global cause of perinatal morbidity and mortality. Several chemicals associated with UOG operations have been linked to negative birth outcomes including the poor growth of infants in the womb and preterm birth.

Particulate matter is most commonly associated to adverse birth outcomes, and is commonly released into the surrounding air during tight oil and shale gas operations.

One study in Colorado examined maternal proximity to natural gas wells and the specific incident of three birth defects recorded. The study found a link between the deaths and their location, which was 10 miles away from a natural gas well.

And as the study concludes, "The developing fetus is particularly sensitive to environmental factors, which include air and water pollution. Research shows that there are critical windows of vulnerability during prenatal and early postnatal development, during which chemical exposures can cause potentially permanent damage to the growing embryo and fetus.



"Many of the air and water pollutants found near UOG operation sites are recognized as being developmental and reproductive toxicants; therefore there is a compelling need to increase our knowledge of the potential health consequences for adults, infants, and children from these chemicals through rapid and thorough health research investigation."

The report: 'Developmental and reproductive effects of chemicals associated with unconventional oil and natural gas operations' is published by Rev Environ Health 2014; 29(4): 307–318. Authors are Ellen Webb, Sheila Bushkin-Bedient*, Amanda Cheng, Christopher D. Kassotis, Victoria Balise and Susan C. Nagel.

Tamsin Paternoster is an reporter with a focus on the environment, social issues and European current affairs.

