During winter, the season when we like to snuggle up warm at home, we spend on average 80% of our time indoors, according to Santé Publique France. Between the windows closed to keep the heat in, the heating running at full blast and the Christmas decorations invading our living rooms, our interiors are transformed into little cocoons… but not always for the better.
Dust, mold, chemical compounds: this explosive cocktail can weaken our immune system, already put to the test by the cold. Result ? We become more vulnerable to winter viruses like the flu, colds or even respiratory infections like Covid-19. What if we adopted some good practices for a festive and healthy home?
Watch out for the trees!
Natural fir: a treasure… loaded with allergens
With its woody scent and fragrant needles, the natural fir tree is an essential symbol of Christmas. But be careful, it can become a real allergen nest.
A freshly cut tree often contains mold. The latter, invisible to the naked eye, develop even more quickly once the tree is placed in a heated room. According to an American study, mold spores can increase by 500% in two weeks when the tree is installed in a living room.
The result is symptoms of respiratory allergies, such as sneezing, nasal congestion or asthma attacks. This meeting of winter microbes is often called Christmas tree syndrome. And, although associated with spring, pollen can also hide on the branches of the fir tree. It may trigger irritation in sensitive people.
Artificial tree: a solution not always without danger
If you are thinking of avoiding allergens by opting for an artificial tree, watch out for unpleasant surprises! Artificial trees are typically made of PVC or plastic, materials that can release volatile organic compounds (VOCs). These chemical substances, detected by Santé Publique France in many household objects, irritate the respiratory tract and can cause headaches, dizziness or allergic reactions.
In addition, stored all year round in the attic or cellar, artificial trees accumulate dust and mites. Without proper cleaning before use, these allergens can be dispersed into the indoor air as soon as they are installed.
Beware of forgotten Christmas decorations in the attic!
Christmas garlands and baubles
Like artificial trees, garlands, baubles and other decorations are often stored in dusty places. Once out, they release these particles into the air, increasing the risk of allergies and rhinitis.
Some Christmas balls or garlands are covered with paints or varnishes containing chemical substances. Prolonged exposure to these products may irritate the eyes, nose or throat, especially in poorly ventilated rooms.
Scented candles and room sprays: a sometimes toxic perfume
To create a warm atmosphere, many use scented candles or room sprays. These products, although attractive, often emit fine particles and VOCs, responsible for indoor pollution.
A study by Ademe (Ecological Transition Agency) shows that certain candles can release substances such as benzene or formaldehyde, both classified as carcinogenic. It is therefore better to limit its use.
Indoor pollution and winter viruses
Dry air weakens your defenses
Winter, with its low temperatures and shorter days, pushes us to spend more time indoors. But, when the heating is on at full speed, the air in our homes often becomes too dry, and our mucous membranes dry out too! These precious natural barriers, present in the nose, throat and bronchi, are there to counter microbes.
But when the humidity drops below 30% (when it should be between 40 and 60%), they lose their effectiveness. Thus, the microscopic cilia which sweep away viruses no longer function optimally and small cracks may appear. Easier for infections to take hold.
Why is it necessary to ventilate, even in winter?
When it's cold, we all have the reflex to keep the windows tightly closed so as not to lose heat. But this thermal comfort can quickly turn into a trap for our health. Indoor air, especially in winter, can be up to 10 times more polluted than outdoor air, according to the Indoor Air Quality Observatory (OQAI). Furniture, paints, scented candles and even plastic Christmas decorations release substances such as volatile organic compounds (VOCs) or fine particles.
And that's not all. In a poorly ventilated environment, winter viruses accumulate and spread. A simple cough or sneeze can disperse contaminated microdroplets into the air, which remain airborne for hours. So ventilate regularly, even in the middle of winter. Ten minutes a day are enough to renew the air and limit the risk of transmission.
Preserving your health: the right reflexes to adopt
To fully enjoy the Christmas spirit, take the right actions to counter winter viruses that could make their way to the holidays.
- Clean your decorations before use: wipe a damp cloth over your Christmas balls, garlands and artificial trees to remove dust.
- Wash decorative textiles (Christmas socks, tablecloths) in the machine: choose natural and ecological decorations.
- Choose materials like wood, glass or recycled paper.
- Avoid products containing questionable paints or plastics.
- Ventilate your house every day: if possible, in the morning and after turning on your light decorations.
- Maintain good indoor humidity: use a humidifier or place a bowl of water on your radiators to prevent the air from becoming too dry.
- Limit artificial fragrances
So, to your garlands… but with caution!
NAMELY
Certain species of mold that colonize Christmas trees can trigger allergies, sometimes severe:
Aspergillus : formidable for immunocompromised people, this mold can cause serious complications.
Penicillium : well known for the production of penicillin, it can however cause allergic reactions in sensitive people.
Cladosporium : very widespread, this mold is responsible for respiratory allergies and can also cause skin infections.
