Benzene Leaking From 99% of Gas Stoves in California Homes, Study Finds

In a study of 159 homes all around California, researchers found that gas stoves are leaking harmful gases, like benzene, which was found in 99% of samples. The leaks are happening even when appliances are turned off, the study found. The authors say more research is necessary to determine how many homes are having these leaks.

The research, published in the journal Environmental Science and Technology, involved trace gas analyses on 185 unburned natural gas samples from 159 homes located in seven geographic regions around the state. California has the highest percentage of gas stove owners in the U.S., with 70% of households cooking with gas-powered stoves and/or ovens. In 99% of the samples collected for the study, benzene leaks were detected. 

According to the Centers for Disease Control and Prevention (CDC), benzene prevents cells from working properly. It can cause various problems, like damaging the immune system or leading to anemia. The International Agency for Research on Cancer (IARC) has also classified the gas as “carcinogenic to humans.”

The analyses also found toluene, ethylbenzene and total xylenes (BTEX). Toluene can lead to nerve, liver and kidney damage. Breathing in ethylbenzene can cause throat and eye irritation and dizziness and has led to hearing and kidney damage in animals, according to the Agency for Toxic Substances and Disease Registry. Total xylenes exposure can also lead to eye, throat and nose irritation as well as headaches, dizziness, loss of muscle coordination and even death at high levels.

The authors found that these leaks occurring while stoves are off can cause indoor benzene concentrations to exceed exposure level of 0.94 ppbv considered safe by the California Office of Environmental Health Hazard Assessment.

“What our science shows is that people in California are exposed to potentially hazardous levels of benzene from the gas that is piped into their homes,” said Drew Michanowicz, a study co-author and senior scientist at PSE Healthy Energy, as reported by The Associated Press. “We hope that policymakers will consider this data when they are making policy to ensure current and future policies are health-protective in light of this new research.”

The report also estimated that there are 4,200 kilograms (over 4.6 tons) of benzene emissions per year leaking from outdoor pipes that are unaccounted for by the state — the equivalent of the yearly benzene emissions from about 60,000 light-duty gas-fueled vehicles.