Benzene, toluene, xylene.

Manganese.

Lead.

When these and other toxic substances ooze out from factories, blow from stockpiles or roil from smokestacks, Denton County’s mix of ozone and greenhouse gases can become a witch’s brew to breathe.

Certain industries — but not all — must report their toxic releases into the air, soil and water to the Environmental Protection Agency each year. Overall, those reported releases have been decreasing in recent years, locally as well as nationally.

DRC/Barron Ludlum

Haze settles over Denton on a November afternoon. Environmental officials continue to seek ways to clean the air in Denton County and several other North Texas counties.

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Some of those toxic releases reported by companies are trucked away for reclamation or recycling, buried in landfills or sent through wastewater treatment plants. Others are released into the air.

Known as the Toxics Release Inven­tory, the program began as part of the Emergency Planning and Community Right-to-Know Act. That law was inspired by Union Carbide’s catastrophic chemical gas releases in Bhopal, India. More than 3,000 people died Dec. 3, 1984, and 10,000 more succumbed within a year. Twenty-five years later, water supplies for 15 communities remain contaminated, according to newspapers in India.

Even as those chemicals reported to the EPA’s Toxics Release Inventory have been decreasing over the years, North Texas’ ambient air quality — a measurement that doesn’t assess those toxins per se, but focuses on ozone made primarily by cars and trucks — cannot meet the minimum federal requirements, which have become increasingly more stringent.

The Environmental Protection Agency signed off two years ago on the state’s now-failed plans to clean the air. This year, however, the EPA challenged additional changes to the air permitting program run by the Texas Commission on Environmental Quality.

Whatever regulators decide is dirtying the air, the news is troubling for pregnant women. A study by researchers released in July at the Columbia Center for Children’s Environmental Health showed that breathing polluted air may affect fetal brain development.

Who reports and who doesn’t

Fifteen of Denton County’s largest businesses have reported to the Toxics Release Inventory since 2002, although not all companies have something to report each year. Small businesses usually don’t have to report their releases to this national inventory.

While the Barnett Shale gas industry is large — well sites, processing units and compression engines move millions of cubic feet of gas per day — no gas drilling or production facility in Denton County has reported toxic releases to the EPA inventory in seven years, since the drilling boom began.

Yet, according to Texas Commission on Environmental Quality documents obtained in an open records request, a single natural gas compression facility can emit 390 tons per year of volatile organic compounds, six times greater than the volatile organic compounds emitted by a cement plant. Recent readings gathered at production facilities by both state and private inspectors show those volatile organic compounds include carcinogens and neurotoxins that are reportable to the inventory.

Recent releases

Ten companies in Denton County — five in Denton, four in Lewisville and Flower Mound, and one in Roanoke — reported about 70 tons of toxic compounds, total, in 2008.

About 67 percent of those releases went into the air. Approximately 48 tons of toxic elements, including lead and lead compounds, went out through either point source emissions (from a smokestack) or fugitive air emissions (leaks).

The EPA released the raw data from the 2008 Toxics Release Inventory earlier this year, in advance of the agency’s own analysis and online research tools, which were released this month. The EPA tracked 650 toxic chemicals reported by 21,000 facilities — more than 3.86 billion pounds of compounds known to cause cancer and reproductive, neurological, respiratory and other problems.

Many facilities are reporting fewer releases in recent years, according to the EPA’s analysis. Overall, the EPA found a 65 percent decrease in toxic releases, based on chemicals consistently reported to the inventory for the past 20 years.

Denton-area companies also are reporting fewer releases, with a 14.6 percent drop in toxic substances released from 2007 to 2008.

Acme’s progress

For example, the latest reports by Acme Brick show a fraction of the hydrogen fluoride and hydrochloric acid released into the air than in previous years.

In 2005, the company released more than 140 tons of those compounds, which can cause skin, lung and other disorders, according to the EPA.

“The Smokestack Effect,” a 2009 analysis of air quality at schools nationwide conducted by USA Today, used some of the older inventory data to look for toxic hot spots.  That older data put the air quality around McMath Middle School, which is just southeast of the plant, among the poorest in the nation, ranking it in the fourth percentile.

Acme installed heavy-duty scrubbers on its smokestacks three years ago to help with emissions, spokesman Jeremy Hargrave said.

In 2008, Acme reported less than 5 tons of those compounds — a 96 percent reduction — and projected about 5 tons for 2009 and 2010.

Local environmentalist Ed Soph had complained about Acme Brick’s toxic releases to the Denton City Council several years ago.

In an interview, Soph noted that the company sped up plans to reduce those emissions, but said people still complain to him about the air quality downwind in South Lakes Park. He questioned whether the company can do more about the sulfur dioxide.

“People have told me that they couldn’t walk in the park some days because the air was so acrid it burned their eyes,” Soph said.

Company spokesman Ed Watson said that the scrubbers Acme bought in 2005, and had installed by 2006, were the best clean-air technology available to them at the time.

“It’s been five years and it’s still the maximum you could put on those stacks,” Watson said.

Local lead releases

Soph turned his attention to United Copper after the 2007 Toxics Release Inventory report.

Beginning in 2005, the company reported air emissions that have inched upward each year — a fraction of a pound in 2005, 3.87 pounds in 2006, 5.67 pounds in 2007 and 4.27 pounds in 2008.

The releases appear to go against a settlement Soph’s environmental group, Citizens for Healthy Growth, reached in November 2000 when United Copper agreed not to install a furnace that smelted old copper, Soph said.

The settlement meant the company was not required to install a special filter that would keep lead from being released into the air.

“They said this wouldn’t happen,” Soph said.

Charlie Banham, a spokesman for United Copper, said that when the company could no longer buy new copper, it had to fire up the furnaces four years ago to melt copper cathodes. Those cathodes are from recycled copper that is 99 percent pure, he said.

The lead releases that the company reported are based on a calculation from the natural gas it burns in the furnaces.

“That is a byproduct of the natural gas burning,” Banham said. “We’re not refining or smelting.”

The company’s current level of lead releases should stay in the single digits “for the foreseeable future,” Banham said.

EPA records show the company projects releasing 4 pounds of lead each year for the next two years.

Bill Peck, United Copper’s operations manager, said there would always be a trace of lead going out the stack because of the burning natural gas.

“We’re not aware of any technology that could get at that,” Peck said.

Two other companies reported similar single-digit lead releases in recent years. Premiere Manufacturing in Flower Mound has reported releasing 5 pounds each year since 2005.

In addition, Peterbilt Motors Co. reported releasing 4 pounds of lead compounds in 2002 and 3 pounds of lead in 2003.

The EPA classifies lead as a persistent, bio-accumulative toxic. In other words, lead has a long half-life after being released in the air. Once inhaled, lead lingers in the body. Lead suppresses the immune system, causes high blood pressure, lowers IQ and can cause nerve, brain and other organ damage, according to the EPA.

A new study at the Cincinnati Children’s Hospital Medical Center showed how children’s brains are damaged through lead exposure. The study used functional MRI technology and provided the first physical evidence showing damage in the parts of the brain that affect decision-making and emotional control.

“The only safe amount of lead is none at all,” Soph said.

PEGGY HEINKEL-WOLFE can be reached at 940-566-6881. Her e-mail address is pheinkel-wolfe@dentonrc.com.