What might be causing your symptoms?
While the jury’s still out to some degree, here are some types of allergens that could be triggering Christmas Tree Syndrome.
Likely the only thorough investigation of Christmas tree allergy, a paper in the Canadian Medical Association Journal concluded that airborne ragweed, grass, and tree pollens on Christmas tree bark or rosin (aka sap) are the likely causes of related symptoms.1 That makes sense because cypress and pine trees, which are often used as Christmas trees, can collect a significant amount pollen from other plants before they are cut down.2 Some weed, grass, and tree pollen, then, likely stays on the trees that end up in your house.4
Pollen-Related Symptoms
Pollen may aggravate asthma symptoms and trigger the following symptoms.3
- Sneezing
- Nasal congestion
- Runny nose
- Watery eyes
- Itchy throat and eyes
- Wheezing
Mold and Dust Mites
The aforementioned CMA Journal study also indicated that scrapings from pine and spruce bark yielded large numbers of potentially allergenic mold spores (specifically those of Penicillium, Epicoccum, and Alternaria).4 While these spores weren’t airborne in relation to this study, another study suggested that mold could be part of the problem, as researchers discovered more than 50 kinds of mold on their Christmas trees.4,5
If mold is to blame, then, faux firs might not be any better than genuine pine. That’s because artificial trees are sometimes stored in damp basements and humid attics, both of which can support mold growth.5 What’s more, these environments may also house dust mites.2 So if you’re sensitized to mold or dust mites, even fake yet festive firs could bring on the sniffles.
Mold-Related Symptoms
Mold may aggravate asthma symptoms and trigger the following symptoms:6
- Nasal congestion
- Runny nose
- Sneezing
- Irritated eyes
- Coughing
- Wheezing
- Itchy throat
Rosin (aka Sap)
To further complicate matters, pine-tree sap (i.e., rosin colophony) can cause contact dermatitis.7 So some people can develop a Chrstimas tree rash after touching its sap.5
Bottom line: The main cause of Christmas Tree Syndrome is debatable. But mold, dust mites, and pollen are suspected causes; plus, rosin could be a sneaky accomplice.