Sneezing in June and July, and you assumed it was grass? In many German and central European cities a fast-spreading tree, the tree of heaven, flowers at exactly the same time. Our test checks IgE to tree of heaven pollen as part of 300 allergens and allergen components, next to grasses and the pan-allergens that can blur the picture.
Tree of heaven (Ailanthus altissima) comes from China and was planted in Europe as an ornamental from the 18th century. It grows very fast, tolerates heat, drought and pollution, and now spreads on its own through cities and along transport routes. The EU lists it as an invasive species.
Its large clusters of yellowish-green flowers open in early summer and smell unpleasant, which earned it the name stink tree. Pollen is spread partly by insects and partly by wind, so most of it stays close to the tree.
In Germany it matters more than most people think. A study in Leipzig found the tree growing widely, recorded its pollen from early June to mid-July, and found IgE to it in 42% of patients whose allergies flared between May and July. In more than half of them, the result could not be explained by cross-reacting pan-allergens.
In the Netherlands it grows in some cities, but less abundantly. In Ireland and Finland it is rare, so it matters mainly on summer trips to central and southern Europe. Spanish allergists have also described it as a local allergen worth considering.
The reported pattern is early-summer hay fever: sneezing, a runny nose and itchy eyes, sometimes with a cough or wheeze in people with asthma. Because it flowers in the middle of the grass season, it is easy to blame grass alone.
Separately, the sap and leaves can irritate the skin of people who cut or handle the tree. That is a contact irritation, not IgE, and this test does not measure it.
From a finger-prick sample, the lab measures IgE to a whole tree of heaven pollen extract as part of 300 allergens and allergen components. Timothy grass components, birch and plane tree are on the same report. So are profilin (Phl p 12) and polcalcin (Phl p 7), two pan-allergens that can make many pollen extracts light up at once, which helps a doctor judge whether a positive is specific to Ailanthus.
A positive result means your blood shows IgE to tree of heaven pollen. That is sensitisation, not a diagnosis. Each value gets a class from Negative to Very high, to discuss with a doctor.
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One finger-prick sample checks IgE to 300 allergens and allergen components, from birch and peanut to cat and house dust mite. Post it to the lab, and about 5 days after it arrives you get a value for every one. Our plain-English guide shows you how to read them. €399 in total, €1.33 per allergen.
In central Europe, tree of heaven flowers from early June to mid-July, with a peak around mid-June. Pollen records from Vienna going back to the 1970s show the season changing as summers get warmer.
People can be sensitised to its pollen. In a Leipzig study, 42% of patients with allergy flare-ups between May and July had IgE to tree of heaven. Whether that causes symptoms is a clinical question for a doctor, who will look at your results and your history together.
Grass is the usual suspect in June, but not the only one. Tree of heaven, lime, plantain and mould spores such as Alternaria are all around then. A broad panel shows which ones your blood actually has IgE to.
