Following the mysterious death of seven cattle near an oil field in Kansas, public health authorities are investigating whether oil drilling could be the cause.

In late December, seven dead cattle were found near an oil field in the Cimarron National Grassland, Kansas, and authorities believe that cows inhaled something toxic, prompting them to deny public access to the 2,500-acre Cimarron National Grassland until at least May.

Six of the cattle were discovered together in a low-lying area, while a seventh was found a short distance away, with local veterinarians identifying the ingestion or inhalation of something toxic leading to pulmonary edema or fluid in the lungs as a possible cause, though the cause of death has not been officially declared.

More specifically, they suspect the cattle may have inhaled hydrogen sulfide—a toxic gas that can be released in the oil and gas drilling process. They haven’t pinpointed the cause officially, but it was enough to implement an emergency order to halt public access to the area for a prolonged period. Related: Fundamentals For Oil Still Bearish, But Sentiment Is Shifting

While the general public is denied access to the grassland, oil and gas companies operating in the Stirrup Oil Field area here are still operational, including Anadarko Petroleum, Merit Energy and Argent Energy.

“It is kind of a unique situation we’re dealing with and I’m honestly afraid we’ll never find the answer,” local veterinarian Tera Barnhardt told media.

It would not be the first mysterious cattle deaths tentatively linked to oil and gas drilling. Related: Japan And Iran Could Keep a Lid On Oil Price Rally

In 2012, 140 cattle were exposed to fracking wastewater in northcentral Pennsylvania when an impoundment was breached. Approximately 70 cows died, and the remainder produced only 11 calves, of which three survived. Another 17 cows died in Louisiana that same year after being exposed to spilled fracking fluid, according to Cornell University.

In New Mexico, hair testing of sick cattle that grazed near well pads found petroleum residues in 54 of 56 animals.

“Cattle that have been exposed to wastewater (flowback and/or produced water) or affected well or pond water may have trouble breeding,” according to Veterinarian Michelle Bamberger and Cornell Professor Robert Oswalt in a 2012 peer study. Related: This Could Be A Big Setback For Iran’s Oil Export Plans

Over the past decade—and particularly since the shale boom—scholars and activists have attempted to link oil and gas drilling to negative impacts on the health of cattle through poisoning of the air, water and soil.

So far, they haven’t been as successful and they would like—and no one has definitively pinpointed the causes of these cattle death—but their message is this: Even though there are still many unknowns here, cattle deaths should in the very least serve as an early warning for humans.

What concerns Bamberger most is that exposed livestock are making their way into the food system—the potential consequences of which we would not see for many years to come.

By Julianne Geiger for Oilprice.com

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