Pollen season can wreak havoc on all sorts of occasions. Research out today shows that it might even put a damper on kids’ test scores, too.

Scientists in Finland studied how high school seniors performed on their final exams taken during the spring. Over a 14-year span, they found students consistently did worse on days when pollen was around than when it wasn’t. Though not definitive, the findings suggest more should be done to prevent pollen from ruining children’s test days, the researchers say.

“To create more equal performance conditions, we should find solutions to reduce exposure to pollen and its harmful effects,” they wrote in their paper, published Tuesday in the Journal of Epidemiology and Community Health.

The pollen effect

Allergic rhinitis, or hay fever, can be an absolute nightmare to suffer through. Sneezing, a runny nose, and watery eyes are just some of the cold-like symptoms people tend to experience. And pollen is an especially common trigger. In the U.S., about one in four adults is allergic to pollen, along with one in five children.

While plenty of research has looked at how these allergies can affect people’s health and well-being, there’s been little attention paid to their potential effects on academic performance, the study researchers say.

The team focused on an easily tracked variable that could be influenced by the appearance of pollen: teens’ matriculation exams, the tests used in Finland and much of Europe to secure graduation from secondary/high school (only some states in the U.S. have a similar concept). These tests are taken in the spring, which is when two pollen-producing plants in the region start to bloom, alder (several Alnus species) and hazel (Corylus avellana). They tracked how all children attending school in the cities of Helsinki and Turku performed on various subject tests between 2006 and 2020—nearly 100,000 kids in total.

Compared to days with no significant pollen in the area, kids performed noticeably worse on days with pollen, the researchers found, though there was some variability. Specifically, children did worse on days with either low or high pollen counts. This could reflect how people and their bodies typically manage these allergies, the researchers say. Low pollen counts could signify the very start of the pollen season, for instance, when people might be caught off-guard. By the time moderate pollen counts are happening, though, people’s immune systems might have adjusted a bit, and/or people are taking antihistamines to reduce their symptoms.

These interventions can only do so much, explaining why high pollen counts start to affect test scores again. Every extra 10 grains per cubic meter of alder pollen was associated with a 0.042 drop in test scores (on a scale from 1 to 66), while each 10 grains of hazel pollen was associated with a 0.17 drop.

That might seem modest, but it’s worth noting the highest daily pollen count during the study period was 521 pollen grains of alder per cubic meter. These results are also across the entire student body, most of whom weren’t allergic to pollen. While it’s possible pollen could hurt non-allergic students on test day as well (kids distracted by other people’s symptoms, for instance), it’s obviously more of a nuisance to children with actual allergies. In other words, these findings might be underselling the typical effect of pollen on a vulnerable student’s test scores.

“The study provides robust evidence of the relationship between short-term fluctuations in pollen levels and students’ academic performance,” the researchers wrote.

What to do about the pollen problem

This research is observational, meaning the findings can only show a correlation between pollen and worse test scores. So it’s at least prudent to conduct further studies to verify and better understand this possible phenomenon.

Given the importance of these exams, pollen could meaningfully be harming some kids’ career prospects, and there are interventions schools and others can take to minimize its impact, the researchers say. That might include scheduling exams outside of pollen season, making sure people are aware of their allergies and the day’s expected pollen count, and making it easier for people to access medications in a timely fashion.

Pollen season is bad enough as is. In an ideal world, it shouldn’t be the reason why some kids do worse in school.