Do Gas Stoves Release Toxic Chemicals?

Gas stoves and other natural-gas appliances can affect indoor air quality. When natural gas burns, it can produce pollutants such as nitrogen dioxide, carbon monoxide, formaldehyde, and fine particles. Small leaks can also release unburned natural gas—mostly methane—and trace volatile organic compounds, including benzene, into the home.

A 2022 Harvard-led study of unburned natural gas from Boston-area homes identified more than 20 hazardous air pollutants, including benzene, toluene, and hexane. Finding a chemical in gas or indoor air does not automatically mean it will cause harm at the levels a person experiences. Health risk depends on the amount present, how long a person is exposed, how often the stove is used, and how well the kitchen is ventilated. Still, gas cooking can be one source of indoor air pollution, especially in small or poorly ventilated spaces.

Is natural gas toxic?

Natural gas is a commonly used cooking fuel; roughly one-third of U.S. households use it. Natural gas itself is primarily methane. In a large release, methane and other gases can displace oxygen in an enclosed area, creating a serious breathing hazard. Natural gas is also highly flammable. A leak may create a fire or explosion risk.

Natural gas is not the same as carbon monoxide. Carbon monoxide is a colorless, odorless gas produced when fuels do not burn completely. A malfunctioning, improperly vented, or poorly maintained fuel-burning appliance can produce dangerous carbon monoxide levels. Proper venting and regular professional inspection of fuel-burning appliances can help prevent carbon monoxide exposure.

What chemicals do gas stoves release?

Natural gas stoves can release carbon monoxide, formaldehyde, and other harmful pollutants into the air. Studies show that air can be unhealthy to breathe when people cook in kitchens with poor ventilation. 

Gas stoves may release different substances depending on whether they are burning or off.

When the stove is…	Possible indoor-air concern
Burning	Nitrogen dioxide, carbon monoxide, formaldehyde, ultrafine particles, and other combustion byproducts
Off	Small leaks of unburned natural gas, which is mainly methane and may contain trace amounts of volatile organic compounds
Malfunctioning or poorly adjusted	Higher pollutant levels from incomplete combustion, including carbon monoxide

A yellow or orange burner flame may suggest incomplete combustion, a dirty burner, or an appliance that needs service. It does not by itself prove that there is a gas leak. A properly functioning gas burner typically produces a mostly blue flame.

Using a range hood that vents outdoors can help reduce cooking-related pollutants. A recirculating hood may capture some grease and particles. However, it does not remove gases from the home as effectively as an outdoor-venting hood. Opening windows, when safe and practical, can also improve ventilation.

Do gas stoves give off methane? 

Yes. Natural gas is mostly methane, and small amounts can escape from connections, valves, or appliances—even when a stove is turned off. Methane itself has no odor. Utility companies add an odorant, often described as smelling like rotten eggs or sulfur, so people can recognize a possible gas leak.

A faint or brief odor near a stove does not necessarily indicate an emergency, but a persistent gas smell, a strong rotten-egg odor, or a hissing sound should always be treated seriously. Do not try to locate the source of a suspected leak yourself.

Are electric stoves safer than gas stoves?

Electric stoves do not burn natural gas, so they do not produce combustion-related pollutants such as carbon monoxide or nitrogen dioxide during cooking. They also do not have a natural-gas leak or open-flame hazard.

However, all cooking appliances can cause burns, fires, and cooking-related smoke or particles. Good kitchen ventilation, close supervision while cooking, and working smoke alarms are important regardless of the type of stove.

How To Safely Use a Gas Stove

A gas stove may be safe if used and maintained properly. If your home has a gas stove, these steps can help reduce indoor-air and safety risks:

• Use a range hood that vents outdoors whenever you cook, particularly when frying, boiling, or cooking for a long time.
• If you do not have an outdoor-venting hood, open a window or door when it is safe to do so.
• Never use a gas stove or oven to heat your home.
• Keep burner ports clean and watch for flames that are consistently yellow or orange.
• Have gas appliances installed, inspected, and repaired by a qualified professional.
• Keep children away from stove burners, knobs, and other gas appliances.
• Learn where your home’s gas shutoff valve is located, but do not delay leaving the home to shut it off if you suspect a leak.
• Install carbon monoxide alarms on every level of the home and near sleeping areas. Test them according to the manufacturer’s instructions.
• Remember that a carbon monoxide alarm does not detect natural gas unless it is specifically labeled as a natural-gas or combustible-gas detector.

Carbon monoxide alarms are an important safeguard, but they do not replace proper appliance maintenance and ventilation. Public health guidance recommends using gas appliances only as intended and having fuel-burning appliances properly vented and maintained.

How to Tell if Your Gas Stove Is Leaking

Possible signs of a gas leak include:

• A strong or persistent rotten-egg or sulfur-like smell
• A hissing or whistling sound near a gas line, appliance, or meter
• Visible damage to a gas line or appliance connection
• Dead or discolored vegetation near an outdoor gas line

Do not rely on a hiss or whistle to rule out a leak; many gas leaks cannot be heard.

A soapy-water test can sometimes reveal bubbles at an accessible outdoor connection or a connection being checked by a qualified person. However, do not use this method—or any other test—if you smell gas indoors or believe there may be an active leak. Leave the building instead. Do not use a flame to check for a gas leak.

What to Do if Your Gas Stove Is Leaking

If you smell gas or suspect a leak, leave the building immediately. Do not stay inside to investigate, open windows, shut off appliances, or gather belongings.

1. Leave the home right away, taking other people and pets with you.
2. Do not light matches, smoke, use a lighter, start a vehicle nearby, or turn electrical switches or appliances on or off.
3. Once you are a safe distance away, call 911 and your natural-gas utility’s emergency number.
4. Do not return to the home until emergency responders or the gas utility say it is safe.

Even a faint gas odor should be taken seriously. Consumer-safety guidance advises leaving the building and calling 911 or the gas supplier from outside; electrical switches and other ignition sources can create a spark.

Symptoms of Natural Gas Exposure

Symptoms of natural gas exposure include:

• Fatigue
• Severe headaches
• Memory problems
• Loss of concentration
• Nausea
• Loss of consciousness
• Breathing difficulties. 

Call 911 if the person is unconscious, having a seizure, or has trouble breathing. Otherwise, contact the Missouri Poison Center at 1-800-222-1222 for treatment advice. Our specially trained nurses and pharmacists are open 24 hours a day, 7 days a week to answer your poison-related questions.