Colorado air pollution regulators spend a lot of time thinking about greenhouse gases that create a smog across the Front Range and contribute to global warming, But this week, they’ll focus on five toxic chemicals that make people sick.
Five new compounds soon will be listed as priority toxic air contaminants in Colorado and, over the next two years, the state’s Department of Public Health and Environment and Air Quality Control Commission will determine out how to regulate them.
The state’s Air Pollution Control Division will recommend five compounds to be regulated to the commission during its two meetings that begin Thursday.
The creation of the list of toxic air contaminants is the result of a years-long effort from environmentalists and public health advocates who want the state to do more to protect people from the pollution that can cause cancers, such as leukemia and lymphoma, and lung diseases, such as asthma, and can harm women’s reproductive health.
For years, environmentalists have complained that air pollution permits issued by the federal and state governments allow companies to pollute with little attention given to how much of those contaminants are dangerous to human health.
“We need to have laws that are based in health that protect people and not just issue permits to pollute,” said Ean Tafoya, director of GreenLatinos Colorado. “It’s what we heard in communities. All these people in our communities were telling us about these strange cancers. People have leukemia. There’s birth defects. There’s something that must be causing these things.”
GreenLatinos and other environmental advocates pushed state legislators to pass a bill in 2022 that orders the Air Pollution Control Division and the Air Quality Control Commission to identify harmful air pollutants, figure out how to quantify their negative health impacts and then force businesses that create those toxins to install measures to limit them.
The new regulations will be rolled out in phases over the course of 2025 and into 2026. The state could add more pollutants, beginning in 2029. The new regulations will impact the oil and gas industry, industrial manufacturers and water sanitation districts.
The five toxic air contaminants being proposed for regulation are:
- Acrolein, which is created when fossil fuels are burned by wood-burning, industrial boilers and reciprocating engines, and it is also used to make a polymer for paints, coatings and adhesives. Acute, short-term inhalation can cause eye and respiratory tract irritation. It is not considered a cancer risk.
- Benzene, a carcinogen released when fossil fuels are burned, including in car exhaust and oil and gas extraction and production. It also is created by cement manufacturing, waste disposal and wood burning. Acute exposure may cause drowsiness, dizziness and headaches, as well as eye, skin and respiratory tract irritation, and unconsciousness at high levels. Chronic inhalation has caused cancer, various blood disorders and affects women’s reproductive organs, the Environmental Protection Agency has reported.
- Ethylene oxide, which is used to make other products such as antifreeze, textiles, adhesives, plastics and detergents. It’s used to sterilize medical equipment, including at Terumo BTC in Lakewood to sanitize medical equipment. It causes cancers in humans, including lymphoma, myeloma, leukemia and breast cancer.
- Hydrogen sulfide, highly toxic gas that smells like rotten eggs. It is released by wastewater treatment facilities, meat processing facilities, petroleum refining, manufacturing of asphalt and roofing material and places where large quantities of manure are stored. It can cause people to pass out due to high exposure. Low exposure can cause headaches, memory loss, balance problems and fatigue. It is not considered a carcinogen but data is limited on how it affects children’s health or women’s reproductive health, according to the EPA.
- Hexavalent chromium is naturally found in food and is necessary dietary supplement. However, it is a by-product of industrial processes such as metal fabricating and by burning coal for electricity. It can leak into water systems and into the air. It can cause cancer and impact the respiratory system, kidneys, liver, skin and eyes, the EPA’s website says.
To create the list, the state health department put together a team of experts to study air monitoring data and computer models of pollution to learn what is in the air and what has the most potential for harming human health, said Jessica Ferko, planning and policy program manager at the Air Pollution Control Division. They also considered where the pollution was being spewed and the number of people exposed to it.
Once the five priority contaminants are solidified, the state will set health-based standards for each compound. That means regulators will try to figure out how much is too much for people to breathe or drink, based on toxicology and epidemiology studies. The Colorado General Assembly must approve those standards.
And once those health-based standards are in place, the state will set rules for how various businesses will control their release into the air and water. Finally, the state legislature will set parameters for pollution permits for those toxics.
As is typical for new rules proposed to the state’s Air Quality Control Commission, there are disagreements between the state, environmentalists and industry over which five pollutants should be addressed.
GreenLatinos, along with other groups including Weld County’s Board of County Commissioners, wants formaldehyde to replace acrolein on the list because it is known to cause cancer and is easier to measure than acrolein.
But Ferko said the task force that created the list saw acrolein as the highest non-cancer health risk. Reducing acrolein emissions also will lower formaldehyde in the air, she said.
Meanwhile, Metro Water Recovery, which treats wastewater for 2.2 million people in metro Denver, and the Colorado Wastewater Utility Council do not want hydrogen sulfide listed, saying it is an unavoidable by-product of treating human waste and it would be almost impossible to reduce emissions of it from their facilities.
Imposing more regulations on hydrogen sulfide would be expensive and would lead to rate increases for customers, according to an opposition letter filed by the wastewater utility council.
As for the oil and gas industry, the decision over which five toxins to list is not as concerning as what comes next, said Kait Schwartz, director of the American Petroleum Institute Colorado, which represents upstream and midstream oil and gas operators.
The state must be careful and thorough in determining how much of each substance is too much for people to breathe, she said.
“We need to be thoughtful not to panic the general public. There are levels that exist out there and we need to be focused on the chronic long-term levels that have a public health impact,” Schwartz said. “There is benzene that exists in the air to begin with. We need to have an understanding of what actually causes the health impacts and the exposures that have an impact.”
Until the state health department releases its plan for setting health-based standards, it’s hard to determine what the long-term impacts on the oil and gas industry will be, Schwartz said.
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