A survey of oil and gas sites in the Barnett Shale found higher than acceptable levels of cancer-causing pollution in one in five, but state environmental regulators said Wednesday the results posed no immediate danger.
"We are going to work on it," said Michael Honeycutt, chief of toxicology for the Texas Commission on Environmental Quality. "It's not a 'drop everything and shut down' level.'"
The testing did find two sites with especially high levels of benzene, which can cause cancer when people are exposed over many years. Those wells, which are located near Dish in Denton County, were ordered fixed immediately. Recent tests show the air is safe, Honeycutt said.
The state agency surveyed 94 oil and gas locations across five counties and found benzene levels "higher than we would like to see" at 19 of them.
"It is clear that gas production facilities can, and in some cases do, emit contaminants in amounts that could be deemed unsafe," according to a TCEQ news release. Regulators emphasized the pollutants are considered dangerous only when people are exposed over many years.
"We have time to work on them," Honeycutt said.
The study also found elevated levels of other pollutants, including carbon disulfide, ethane, and isopentane, but none at levels that would cause adverse health effects, the agency said.
The testing was conducted over several months last year in Denton, Wise, Parker, Hood, Johnson and Tarrant counties.
The TCEQ said it would continue to monitor the air in the area and work with companies to reduce emissions.
In December, the agency conducted similar surveys in Fort Worth and found no health danger within city limits.