For many families, the climax of Christmas anticipation culminates in setting up a real fir tree in the living room and decorating it festively with baubles, garlands and candles. Sensitive people, however, react allergically to the coniferous tree. This manifests itself in hay fever-like reactions such as a cold or cough. Headaches and fatigue can also occur. But a Christmas tree can also trigger serious problems ranging from respiratory complaints to an asthma attack with shortness of breath. This is how rhinitis or asthma symptoms manifest themselves. If you have pre-existing lung or respiratory conditions such as asthma, Christmas tree syndrome can affect you more severely. In the worst case, breathing difficulties increase dramatically and develop into pneumonia.
You can recognise Christmas tree syndrome by these symptoms:
- Rhinitis with a runny or blocked nose
- itchy or watery eyes
- Coughing, wheezing, chest pain up to shortness of breath
- Fatigue and sluggishness
What triggers the Christmas tree syndrome?
The allergic reactions are not triggered by the Christmas tree itself. Rather, mould spores that grow on the coniferous tree are the cause of Christmas tree syndrome. These mould spores settle naturally on the tree. This is not a problem in nature. However, if you bring your Christmas tree into your home, the warm heating air accelerates the multiplication of the fungi. This greatly increases the number of mould spores in the indoor air. In addition, most Christmas trees are cut weeks before the festivities and then stored outside in the humid air: the best conditions for mould.
Which moulds trigger the Christmas tree syndrome?
If a Christmas tree is in the room, a clear increase in mould spores in the room air is already measurable after four days. Depending on the ventilation behaviour, the spore concentration can even increase tenfold within two weeks. While under normal circumstances between 500 and 700 spores per cubic metre of air can be detected, the levels can rise to around 5,000 spores per cubic metre of air. If the values exceed the limit of more than 700 spores per cubic metre, it can be assumed that mould is growing in the room. If the spores are inhaled, this can cause an allergic reaction. Among the mould species that colonise Christmas trees are many that trigger allergies.
- Aspergillus: Especially dangerous for people with a weakened immune system.
- Penicillium: This mould is used to make penicillin and can cause allergic reactions in some people.
- Cladosporium: The common mould causes skin infections as well as allergic reactions.
According to the Robert Koch Institute, five out of 100 people are allergic to mold. For one in three people with a hypersensitivity (atopy), inhaling even small quantities triggers an allergic reaction. Children are particularly affected: Around one in ten children is sensitive to mold. Repeated contact with mold spores promotes allergies.
Sensitive people can also react to the terpenes contained in the tree resin. Some Christmas trees are also treated with pesticides. These substances further irritate the respiratory tract.
Tips to prevent Christmas tree syndrome
Mould spores, terpenes, pesticides: that's where an artificial tree seems like a good alternative. However, artificial Christmas trees are made of polyvinyl chloride, petroleum-based plastic. Bear in mind, however, that a plastic tree can, on the one hand, emit volatile organic chemicals and, on the other hand, become dusty due to storage. This in turn causes reactions in people who are allergic to house dust. Of course, this is also a problem with Christmas decorations. Therefore, you should clean both your artificial tree and the decorations thoroughly before decorating your rooms for Christmas. If you don't want to do without a real Christmas tree, you should prevent the Christmas tree syndrome with the following tips.
- Opt for a freshly felled tree - preferably from a regional forestry operation. If you cut your fir yourself, you avoid lengthy storage and transport conditions that promote mould growth.
- Do not bring the Christmas tree into the flat as early as Advent, but only for Christmas. Clean the tree before you put it in the house. Shake or hose it down well beforehand. Ideally, use a leaf blower to remove as many pollen grains as possible.
- Have the tree cleaned and decorated by a non-allergic person.
- Since mould spores increase with each day in the warm indoor air, you should ideally only leave the tree up for seven days.
- Check the air quality with an air measuring device such as the air-Q and take countermeasures when limit values are reached.
Here's what you should look out for when decorating your tree
Christmas trees are not the only cause of allergic reactions. The German Allergy and Asthma Association (DAAB) also points out the dangers of Christmas decorations. For example, paraffin candles vaporise soot and solvents, which can trigger headaches, allergic skin rashes or asthma attacks in sensitive people. Tinfoil tinsel, on the other hand, is hardly used any more. This is a good thing, because these tree decorations contain lead, a heavy metal that is harmful to health. Here, too, children under the age of three are particularly affected. They react sensitively to lead with coughs, skin rashes and headaches.
Low-allergy alternatives as Christmas decorations:
- Stars or balls made of paper, straw, wood or glass
- Salty biscuits
Our test results
Shortly before Christmas, we wanted to know and measured our indoor air with the air-Q: before and after putting up the fir tree. At 6 p.m. we brought the tree into the living room, set it up an hour later and at 9 p.m. we took down the net and shook the tree so that the branches could spread out. It is clear from our test measurement that there is a peak in the PM₁₀ values after the tree is put up. Afterwards, the particulate matter value regulates itself again and settles in the harmless range. However, it remains higher than without a tree in the room. It can therefore be deduced that the proportion of particles in the room air rises sharply. Based on the particle size to which the air-Q reacts, it is probably particulates or mould spores. At this point, allergy sufferers would show symptoms.
Note: The sensors for PM₁₀ particles are sensitive and react to air fluctuations. Thus, air changes due to combustion, road pollution or cooking fumes are also reflected in the evaluation of the air-Q.
Monitor air quality with the air-Q
The air quality in rooms is not constant, but is influenced by our breathing or by placed furniture, wallpaper or carpets. Therefore, it is necessary to control them. The air-Q air analyser continuously records all measured variables such as humidity, temperature and air pollutants and warns when limit values are reached. With the help of up to 14 sensors and its own Health and Performance Index™, the air-Q is by far the most comprehensive air measuring device - made in Germany. You can see on the device and in detail via the air-Q app and web app how your indoor air is composed and avoid negative side effects of polluted air such as the Christmas tree syndrome.
(Cover photo: Shutterstock/ irinaneva)
