California environmental health officials announced Thursday that two toxic air pollutants present in California’s ambient air, acrolein and ethylene oxide, appear to be even stronger carcinogens than previously known.
The draft findings from the state Office of Environmental Health Hazard Assessment found that the chemicals could cause an estimated cancer risk 10 times greater than that of benzene, a serious carcinogen linked to leukemia and other cancers. This is the first step in the review process before final risk values are adopted.
OEHHA Director Chris Thayer said, “If the initial air monitoring results go well, and if the developed draft cancer values are close to being final, then each air pollutant poses an unacceptable cancer risk.”
The update reflects the state’s evolving understanding of the state’s most dangerous pollutants, which over the decades has shifted from visible pollutants like smog to more invisible pollutants that cause cancer, heart disease and other health harms.
This comes two months after the Trump administration’s Environmental Protection Agency withdrew standards on ethylene oxide, or ETO, in an effort to save millions of dollars in compliance costs for facilities that use the chemical for medical sterilization. The administration said it took the action to “protect the supply of essential medical equipment”, but experts said the move would expose more people to health risks.
It also follows a new national report from the American Lung Assn. It found that 82% of Californians live in counties with unhealthy air, nearly double the national average.
“This is an important step forward in better understanding the harms of pollutants that impact the health of Californians,” said Will Barrett, assistant vice president for nationwide clean air policy at the American Lung Association, who reviewed the state’s findings for The Times. “Following the latest available health science to determine risk is important to protect health.”
Ethylene oxide is a colorless gas that is often used in the sterilization of medical instruments, especially those that cannot be cleaned using steam or radiation.
Acrolein can form when materials such as cigarettes, e-cigarettes and vapes, wood, plastics and gasoline for cars, trucks, ships and planes burn. It can also be released from cooking fats and oils at high temperatures, and it has been found in water produced by oil and gas operations and is an ingredient in some pesticides used in irrigation canals.
Officials said people can take steps to protect themselves from exposure to acrolein in everyday life, such as smoking tobacco or using e-cigarettes and vaping products, avoiding smoke from wildfires or exhaust from diesel and gasoline vehicles and appliances — much of which can also help reduce ethylene oxide exposure. When cooking with oil or fat, people should avoid very high temperatures and use the range hood fan when possible.
While both chemicals have been present in the state’s air for years, OEHHA’s new assessments are based on the latest science on health risks, officials said. The agency said the cancer risk from both acrolein and ethylene oxide is estimated to be more than 800 in 1 million – comparable to the cancer risk from diesel exhaust when it first emerged as a major public health concern in the 1990s.
In response to the findings, Gov. Gavin Newsom’s May budget amendment released Thursday includes $2.5 million in funding for the California Air Resources Board and OEHHA in support of research to help reduce people’s exposure to acrolein and ethylene oxide. Officials said the funding will help the state identify and track major sources of chemicals and translate the findings into public health policy outcomes.
OEHHA’s assessment provides the first cancer risk value for acrolein since it was classified possibly carcinogenic to humans In 2020 by the International Agency for Research on Cancer. Ethylene oxide was previously identified as a carcinogen by the state, but the new assessment updates its risk level based on new research. Risk calculations are based on air monitoring data, which varies across the state depending on location, nearby sources, and other factors.
Officials said the findings underscore the state’s efforts to strengthen environmental protection measures for residents at a time when federal officials want to loosen them.
“Especially in light of some of the national rollbacks we’re seeing on protections for public health, this really underscores how important the work we’re doing in California is,” said Courtney Smith, chief deputy executive officer of the Air Resources Board. “Not only to protect the health of Californians, but also to ensure that rigorous, solid science is available to other entities that want to seek additional protections.”
According to the federal government, short-term exposure to EtO by inhalation can cause headache, dizziness, nausea, fatigue, respiratory irritation and other adverse health effects. Agency for Toxic Substances and Disease Registry. Long-term exposure increases the risk of cancers of the white blood cells, such as non-Hodgkin lymphoma, as well as breast cancer.
Inhaling acrolein may irritate the nose and throat and reduce the rate of breathing. long-term exposure, such as through cigarette smoke, has been Joined together For the development of asthma, chronic obstructive pulmonary disease and respiratory cancer.
The findings come even as California continues to receive poor grades on air quality. American Lung Association. annual air condition The report found that the five US counties with the worst smog pollution are in California. Bakersfield was the metropolitan area with the worst levels of year-round particle pollution for the seventh consecutive year, while Los Angeles was the city with the worst ozone pollution, as it has for 26 of the last 27 years.
“Californians face some of the greatest smog and soot challenges in the country, but our air agencies have followed the science to create policies and programs that drive real progress,” Barrett said. The state’s latest assessment “points to the need for ongoing local efforts while the federal government ignores the science and opens the door to more pollution. California must continue to invest in things like truck fleet cleanups, comprehensive public education, and the underlying science to guide policies to protect health.”
Thursday’s announcement begins a 45-day public comment period, after which the draft assessment can be revised for additional public comment, peer review by the state’s Scientific Review Panel on Toxic Air Contaminants and before eventual adoption.
