Air pipes

Study: Carcinogenic Gas Leak from AC Stoves and Pipes

Gas stoves in California homes are leaking cancer-causing benzene, researchers found in a new study published Thursday, though they say more research is needed to understand how many homes are leaking.

In the study, published Thursday in Environmental Science and Technology, the researchers also estimated that more than 4 tons of benzene per year are released into the atmosphere through outdoor pipes that carry the gas to buildings around California – l equivalent to the benzene emissions of nearly 60,000 vehicles. And these emissions are not taken into account by the State.

The researchers collected gas samples from 159 homes in different areas of California and measured to see what types of gases were emitted in the homes when the stoves were turned off. They found that all of the samples they tested contained hazardous air pollutants, such as benzene, toluene, ethylbenzene and xylene (BTEX), all of which can cause adverse health effects in humans with a chronic exposure or acute exposure in larger quantities.

According to the National Cancer Institute, of most concern to researchers was benzene, a known carcinogen that can lead to leukemia and other cancers and blood disorders.

The finding could have major implications for indoor and outdoor air quality in California, which has the second-highest level of residential natural gas use in the United States.

“What our science shows is that Californians are exposed to potentially dangerous levels of benzene from the gas that is piped into their homes,” said Drew Michanowicz, study co-author and lead researcher at PSE. Healthy Energy, an energy research and research center. political institute. “We hope policy makers will take this data into account when developing policies to ensure that current and future policies protect health in light of this new research.”

Homes in Greater Los Angeles, North San Fernando Valley, and San Clarita Valley had the highest gas levels of benzene. Stove leaks in these areas could emit enough benzene to significantly exceed the limit deemed safe by the California Office of Environmental Health Hazards Assessment.

This particular finding came as no surprise to area residents and healthcare workers who spoke to The Associated Press about the study. That’s because many of them experienced the nation’s largest known natural gas leak at Aliso Canyon in 2015.

At the time, 100,000 tons of methane and other gases, including benzene, leaked from a failing well operated by Southern California Gas Co. It took nearly four months to bring the leak under control and caused headaches, nausea and nosebleeds.

Dr. Jeffrey Nordella was a doctor at a local urgent care center at the time and remembers being intrigued by the variety of symptoms patients were experiencing. “I didn’t have much to offer them” except to help them try to detox from the exposures, he said.

It was an acute exposure to a large amount of benzene, which is different from chronic exposure to smaller amounts, but “remember what the World Health Organization said: there is no ‘there is no safe level of benzene,’ he said.

Kyoko Hibino was one of the residents exposed to toxic air pollution as a result of the Aliso Canyon gas leak. After the leak, she began having a persistent cough and nosebleeds and was eventually diagnosed with breast cancer, which has also been linked to benzene exposure. Her cats have also started having nosebleeds and one recently died of leukemia.

“I would say take this study very seriously and understand how bad (benzene exposure) is,” she said.


Follow Drew Costley on Twitter: @drewcostley.


The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute Department of Science Education. The AP is solely responsible for all content.