Exposure to gas stoves in homes is worse for your health than secondhand cigarette smoke

Millions of homes are at risk of elevated benzene exposure every time their gas stoves are ignited, warns a recent Stanford-led study.

Benzene is a chemical associated with an increased risk of leukemia and other blood cell cancers. It appears to become an unwelcome guest when residents prepare meals on their gas stoves.

According to the research, the activation of a single gas cooktop burner or setting a gas oven to 350 degrees Fahrenheit can elevate indoor benzene levels. Shockingly, these levels often exceed those found in secondhand tobacco smoke.

Benzene from gas stoves is a menace to homes

To add to the concerns, benzene, it turns out, doesn’t confine itself to the kitchen. The harmful carcinogen spreads throughout the house. It will linger for hours in the air, as outlined in the paper published on June 22 in Environmental Science & Technology.

Rob Jackson, the study’s senior author, explains: “Benzene forms in flames and other high-temperature environments, such as the flares found in oil fields and refineries. We now know that benzene also forms in the flames of gas stoves in our homes.”

Jackson is the Michelle and Kevin Douglas Provostial Professor and professor of Earth system science at the Stanford Doerr School of Sustainability. He adds a rather alarming note on the efficacy of exhaust fans: “Good ventilation helps reduce pollutant concentrations, but we found that exhaust fans were often ineffective at eliminating benzene exposure.”

What the researchers learned about gas stoves

The research reveals that the indoor benzene concentrations resulting from gas stoves can sometimes be worse than average levels from secondhand smoke.

It also shows that benzene doesn’t respect boundaries; it can migrate into rooms far removed from the kitchen. This means that bedrooms can harbor benzene levels exceeding national and international health benchmarks.

Another disturbing find is that even range hoods designed to reduce pollutant concentrations are not always successful. This is especially true when it comes to benzene, and this remains true even when the hoods vent outdoors.

Benzene does the most damage when gas stoves are turned on

Previous studies have mainly investigated benzene emissions from stoves when they are turned off and leaking. This study, however, is the first to focus on emissions when a stove or oven is in active use.

The findings indicate that gas and propane burners and ovens discharge 10 to 50 times more benzene than their electric counterparts. Induction cooktops, on the other hand, emit no detectable benzene at all.

The rate of benzene emitted during combustion far outstrips the emission rates of benzene from unburned gas leaks identified in recent studies.

What about food that is exposed to benzene?

The researchers went even further to scrutinize whether the foods being cooked emit benzene. They found zero benzene emissions when pan-frying salmon or bacon. It’s clear from their findings that all benzene emissions measured emanated from the fuel used rather than the food cooked.

Earlier studies led by Stanford have shed light on how gas-burning stoves inside U.S. homes leak methane with a climate impact equivalent to the carbon dioxide emissions from about 500,000 gasoline-powered cars.

They also expose users to pollutants such as nitrogen dioxide, which can trigger respiratory diseases. Indeed, a 2013 meta-analysis concluded that children living in homes with gas stoves faced a 42% greater risk of asthma compared to those living in homes without gas stoves. Additionally, a 2022 analysis attributed 12.7% of childhood asthma in the U.S. to gas stoves.

Reflecting on his personal circumstances, study lead Yannai Kashtan, a graduate student in Earth system science, says, “I’m renting an apartment that happens to have an electric stove. Before starting this research, I never thought about it twice, but the more we learn about pollution from gas stoves, the more relieved I am to be living without a gas stove.”

How to reduce gas stove pollutants

The researchers suggest several ways to reduce exposure to pollutants from gas stoves.

Adequate ventilation, such as using a range hood or keeping a window open, is recommended.

In addition, cost-effective measures can be adopted. One such idea is utilizing portable induction cooktops, which are often available for less than $50.

Electric kitchen appliances, like tea kettles, toaster ovens, and slow cookers, can also be used as substitutes.

For homeowners looking to replace gas appliances, there are a number of financial aids available. They can take advantage of state and local rebates. Also, low- or no-interest loans are available, designed to offset the cost of replacing gas appliances.

Currently, federal tax credits are on offer. Federal rebates are expected to be available later this year or sometime in 2024.

The High Tide Foundation funded this groundbreaking study. Alongside Rob Jackson, who also serves as a senior fellow at the Stanford Woods Institute for the Environment and the Precourt Institute for Energy, a diverse team of researchers contributed to the work.

This collaborative effort sheds a vital light on the risks of gas stoves, ultimately providing crucial knowledge to homeowners and policy-makers alike.

More about gas stoves

A gas stove is a cooking appliance that uses natural gas, propane, butane, liquefied petroleum gas, or other flammable gas as fuel. They have been a staple in kitchens around the world for many years due to their reliability, precise temperature control, and immediate responsiveness.

Here’s a deeper look at what you might want to know about gas stoves:

Design and Operation

Gas stoves typically have four main components: the burners, the grates, the control knobs, and the oven. The burners are where the gas flows out and ignites to provide heat. The grates sit above the burners and hold pots and pans at an appropriate distance from the flames.

The control knobs allow you to regulate the amount of gas that flows to the burners. This controls the heat level. Lastly, the oven operates similarly, with gas supplying the heat, but usually includes a thermostat for temperature regulation.

Benefits

Heat Control

One of the biggest advantages of gas stoves is the ability to adjust the heat levels instantly. As soon as you turn the knob, the flame size adjusts accordingly, giving you immediate heat control. This feature is particularly appreciated by chefs and cooking enthusiasts.

Heat Distribution

Gas burners also distribute heat evenly across the bottom of cookware, leading to more uniform cooking.

Cost-effective

While the initial investment for a gas stove might be higher, the cost of natural gas or propane tends to be lower than electricity. This makes it more cost-effective in the long run in many regions.

Works during Power Outages

Unlike electric stoves, gas stoves can still be operated during a power outage. This can be a significant advantage in areas prone to storms or other disruptions.

Drawbacks

Safety Concerns

Gas stoves can pose safety risks, such as gas leaks, which can lead to fires or explosions if not promptly detected and addressed. There’s also the danger of carbon monoxide poisoning if the stove is improperly ventilated.

Air Quality

As per the latest research, which includes the study you mentioned earlier, gas stoves can emit harmful substances. These include nitrogen dioxide, carbon monoxide, and formaldehyde, in addition to benzene, affecting indoor air quality and potentially leading to health problems.

Cleaning

Gas stoves, with their grates and burner caps, can be more difficult to clean than smooth electric cooktops.

Environmental Impact

Although natural gas is often marketed as a clean energy source, it does contribute to greenhouse gas emissions. When burned, it releases carbon dioxide, a greenhouse gas.

Additionally, methane, a primary component of natural gas and a potent greenhouse gas, can leak during the production and transport of natural gas.

Furthermore, a recent study showed that gas stoves could leak small amounts of methane even when they’re turned off. The researchers found that these leaks across millions of stoves could have a climate impact equivalent to the carbon dioxide emissions from about 500,000 gasoline-powered cars.

Overall, while gas stoves have their benefits, it’s crucial to consider their drawbacks, especially in terms of safety and environmental impact. Alternatives like electric or induction cooktops can be safer and more environmentally friendly options, depending on your local electricity source.

More about benzene

Benzene is a colorless, sweet-smelling chemical compound that is highly flammable. It’s an organic chemical compound with the molecular formula C6H6. This means it’s composed of six carbon atoms joined in a ring with one hydrogen atom attached to each carbon atom. This ring structure, also known as an aromatic ring, gives benzene its unique chemical properties.

Uses and Production

Benzene is a significant part of crude oil and is therefore a principal component in gasoline. It’s used as a starting material in the manufacture of a wide variety of chemicals. These include plastics, resins, synthetic fibers, rubber, dyes, detergents, pharmaceuticals, and pesticides.

The most widely practiced method to produce benzene is by the catalytic reforming of naphtha, a petroleum derivative. Other methods include toluene hydrodealkylation, toluene disproportionation, and steam cracking.

Exposure and Health Effects

People can be exposed to benzene in the environment from gasoline fumes, automobile exhaust, emissions from some factories, and waste water from certain industries. It’s also found in tobacco smoke.

Chronic exposure to benzene mainly harms the bone marrow, the production site of new blood cells. This can lead to a decrease in red blood cells leading to anemia. It can also cause excessive bleeding and impact the immune system, increasing the chance for infections.

Benzene is classified as a carcinogen by several health agencies, including the International Agency for Research on Cancer and the U.S. National Toxicology Program. It has been linked to leukemia and other blood cell cancers.

Environmental Impact

When released into the atmosphere, benzene reacts with other chemicals and breaks down within a few days. Its breakdown products can be deposited by rain, but most of them end up in the soil or in surface water. Benzene can pass into the soil from the air or from water. It can also move from soil into underground water.

Regulation

Given the health risks associated with benzene, many countries have set limits for benzene in drinking water, in air, and in the workplace. The U.S. Environmental Protection Agency, for example, has established a maximum contaminant level for benzene in drinking water at 0.005 milligrams per liter.

The Occupational Safety and Health Administration (OSHA) has set a permissible exposure limit of 1 part benzene per million parts of air in the workplace during an 8-hour workday, 40-hour workweek.

In summary, while benzene is an important industrial compound, it’s also a potent carcinogen. Exposure should be minimized, and safety regulations and guidelines should be strictly followed when handling it.