A study on a live Christmas tree showed that they could be a source of allergenic mold. Measurements showed that mold counts were 800 spores per cubic meter of air during the first three days, which are just about normal levels. However, mold counts began rising from the fourth day on, and by day 14, when the tree was taken down, the measure was 5,000 spores per cubic meter of air.
Mold allergies affects about 15 percent of the population. Allergic reactions can include nasal, eye, and throat irritation, nasal stuffiness, and headache. There is also a link between mold and asthma attacks, and a risk of invasive fungal disease for those people with compromised immune systems.
Most Christmas trees are cut in advance of the holidays and stored in a moist environment, making them a likely mold source. However, artificial trees and ornaments collect dust in storage and are therefore another possible source of allergy irritation.
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