Asthma Triggers At Home You Didn’t Realize Were Making You Sick

August 15, 2025/Andrew Le

Asthma triggers in your home that you may overlook can flare up in ways you never expect. From cooking meals to using air fresheners, these routines can quietly fill your indoor air with harmful particles and chemicals.

The danger grows when these triggers build up inside. Gas stoves can release nitrogen dioxide that irritates the lungs, while scented sprays and cleaning products can release volatile organic compounds. Dampness and hidden mold spread allergens, dust mites thrive in bedding, and pests like cockroaches and mice add even more strain to your breathing.

🔑Key takeaways

➤ Gas stoves can release nitrogen dioxide that irritates the lungs, making them one of the most common asthma triggers found in the home, especially for children in households without good ventilation.

➤ Cleaning sprays, air fresheners, and other scented products release chemicals that can trigger or worsen asthma, with frequent use linked to higher asthma rates in both children and adults.

➤ Dampness and hidden mold are strong asthma triggers often lurking in the home because they release allergens and toxins that can raise asthma risk significantly, even without visible signs of mold.

➤ Bedding often contains dust mites that can worsen asthma, and while reducing dust mites lowers allergen levels, it does not consistently improve symptoms without medication.

➤ Cockroach and mouse allergens are some of the most harmful asthma triggers in your home, especially for children, leading to more symptoms, hospital visits, and missed school days.

Gas cooking and indoor fumes

Children living in homes with gas cooking have a higher chance of developing asthma compared to those in homes without it. A review of multiple studies showed that breathing in nitrogen dioxide (NO₂) from gas stoves is also linked to more cases of wheezing in children.

Another study found that gas and propane stoves release enough NO₂ indoors to reach levels that can harm health. It reported that this pollution can trigger asthma in many children. The problem is worse in smaller homes, where the gas fumes build up faster, and in households that do not use effective kitchen ventilation. Certain communities, including some racial and ethnic groups, are exposed more often and at higher levels. 

For example, a child in a small apartment where cooking is done daily on a gas stove without a range hood may be exposed to harmful NO₂ concentrations that linger in the air, increasing their risk of asthma flare-ups. To avoid this, use a range hood that vents outside during cooking, open windows to improve airflow, or consider switching to an electric or induction stove to eliminate gas-related emissions altogether.

Cleaning products and fragrances

Cleaning products and fragrances can release volatile organic compounds (VOCs), which are chemicals that easily become vapors or gases at room temperature, and other irritants that stay in indoor air, triggering or worsening asthma. Scented sprays and air fresheners are especially risky because they are often used in enclosed spaces where exposure is higher.

According to a study, data from the Canadian Healthy Infant Longitudinal Development (CHILD) Cohort Study of 3,455 participants showed that frequent cleaning product use during infancy increased the odds of recurrent wheeze, wheeze with atopy, and asthma by age 3. Scented and air-refreshing products posed the highest respiratory risk, with results from the European Community Respiratory Health Survey showing that weekly cleaning spray use was linked to higher asthma incidence, and air-refreshing sprays carried an even greater risk. About one in seven adult asthma cases in that study could be attributed to spray use.

According to another study, 64.3% of asthmatics in the US reported adverse health effects from fragranced products, including respiratory problems (43.3%) and asthma attacks (27.9%). Nearly half reacted to being near someone wearing fragrance, and more than a third lost workdays or jobs because of exposure. 

According to another study, VOCs such as benzenes, toluenes, xylenes, and formaldehyde, common in fragranced products, are linked to asthma and allergy onset or worsening, though evidence quality is mixed. For example, using air fresheners or scented cleaning sprays in enclosed spaces can release these VOCs into the air, triggering wheezing or shortness of breath in sensitive individuals. 

To avoid this, choose fragrance-free or low-VOC products, keep windows open for ventilation during cleaning, and avoid spraying products in areas without adequate airflow.

Dampness and hidden mold

Exposure to dampness and mold in homes significantly increases the risk of developing asthma. A meta-analysis of 16 studies found that dampness raised the risk by 33%, visible mold by 29%, and mold odor by 73%. Mold odor had the strongest link, pointing to mold-related agents as likely contributors to asthma onset. In contrast, water damage alone was not significantly associated with asthma. These findings suggest that hidden mold, even without visible growth, can still be a serious health hazard.

Similarly, a study reported that children living in moldy homes faced a 53% higher asthma risk in case-control studies and a 15% higher risk in cohort studies. Cross-sectional data also linked mold exposure to poorer lung function in children. It is noted that damp, moldy environments release a mix of irritants, toxins, and allergens, which can trigger or worsen asthma in genetically susceptible individuals.

Another systematic review further confirmed these associations in a review of 56 studies, finding consistent and significant links between dampness indicators and childhood asthma. Moldy odor again posed the highest risk, followed by visible mold spots, water damage, and damp stains. The increased risk for ever-diagnosed asthma ranged from 19% to 54% depending on the indicator. The results reinforce the need to reduce indoor dampness to prevent asthma in children, such as by repairing roof leaks promptly, improving home ventilation, and using dehumidifiers in humid rooms to keep moisture levels low.

Bedding and dust mites

Bedding can be one of the biggest sources of dust mite exposure, making it a key indoor asthma trigger. According to a large randomized controlled trial involving 1,122 adults with asthma found that allergen-impermeable bed covers significantly reduced dust mite allergen concentrations in mattress dust at six months compared to controls. However, this drop in allergen levels did not lead to measurable improvements in lung function, asthma symptoms, or the ability to stop inhaled corticosteroids, and the benefit was not sustained at 12 months.

Similarly, a study reviewed 55 randomized trials involving 3,121 mite-sensitive asthma patients and concluded that both physical methods, like mattress encasings, and chemical control measures failed to produce significant clinical improvements. Across trials, there were no meaningful changes in morning peak flow, asthma symptom scores, medication use, or the number of patients reporting improvement.

In a more focused study of 30 patients with moderate to severe asthma and dust mite allergy. Anti-allergic mattress covers lowered Der p1 concentrations in carpet-free bedrooms over one year, yet airway hyperresponsiveness, lower airway symptom scores, and peak flow values remained unchanged. Only nasal symptoms showed a modest reduction, and quality of life improvements were similar to the placebo group.

Reducing bedroom dust mite exposure can be done by washing bedding weekly in water hotter than 60°C, removing untreated underlays, and sun-airing bedding. Freezing soft toys overnight can kill mites, but washing in hot water is needed to remove allergens. Vacuuming with a HEPA filter, damp-dusting, and keeping bedrooms dry and well-ventilated can also help.

However, while these steps can cut allergen levels but it has not shown consistent asthma improvement from dust mite reduction alone. It is emphasized that controlling asthma with preventer medications remains the most reliable approach, with allergen avoidance as a supportive measure rather than a stand-alone solution.

Pests

Indoor allergens from pests can worsen asthma, especially in children. Exposure to cockroach droppings, mouse urine, or pet dander has been linked to more symptoms, hospital visits, and missed school days.

Cockroach and mouse allergens

According to one study, cockroach allergens play a major role in worsening asthma among inner-city children. Over one-third of the children tested were allergic to cockroaches, and half of their bedrooms had high allergen levels. Children who were both allergic and exposed to these high levels were more likely to be hospitalized, make frequent emergency visits, and miss more school days. They also had more nights of disturbed sleep due to asthma flare-ups.

Another study showed that reducing cockroach allergens in the home can ease asthma symptoms. In the trial, families received tailored home interventions, such as sealing cracks where cockroaches enter, using safe pest control methods, and regularly deep-cleaning bedrooms led to a clear drop in cockroach allergen levels. This reduction was linked to fewer days with asthma problems and an overall improvement in health.

Moreover, a study found that mouse allergens were almost everywhere in inner-city homes, with 95% of households showing traces. Nearly half reported mouse problems in the past year, and almost a third had visible signs of mice. Homes with cockroach infestations often had higher mouse allergen levels, showing how these pests can be linked.

It is also reported that one in four children with asthma is allergic to mouse allergens. The study also found that exposure could affect the immune system in complex ways, even if the amount of allergen in the home was high.

💡Did you know

A study reviewed data from over 77,000 children to see if having a cat or dog early in life caused asthma. It found no clear link between pet ownership and asthma overall. 

However, children who were allergic to cats or dogs were more likely to have asthma if they lived with these pets, while those without allergies might even get some protection from early pet exposure.

Wrap up

Asthma triggers found in your home often hide in everyday routines, making them easy to overlook. Gas stoves, scented cleaning products, and air fresheners can fill indoor air with chemicals that irritate your lungs. Damp areas and hidden mold quietly release allergens, while bedding can harbor dust mites that worsen symptoms. Pests like cockroaches and mice add even more risk, especially for children.

These triggers can build up over time, raising the chances of flare-ups and hospital visits. By improving ventilation, controlling dampness, and reducing exposure to allergens, you can lower these risks and make your home a safer place for breathing.

Frequently asked questions

Can asthma triggers be different for each person?

Yes. Some people react to only a few triggers, while others react to many. Your triggers depend on your sensitivities and environment.

How can I find out what my asthma triggers are?

Keep a symptoms journal. Track what you were exposed to before symptoms started. Some triggers can cause delayed reactions.

Can exercise cause asthma symptoms?

Yes. This is called exercise-induced bronchoconstriction. It often happens in cold air but can be managed with proper treatment.

Can emotions trigger asthma?

Strong emotions like laughter, anger, fear, or crying can change your breathing and trigger symptoms in people with asthma.

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