Pollen exposure linked to matriculation exam performance – strongest effect in mathematical subjects
The study focused on exposure to alder and hazel pollen, as these species flower during the spring matriculation exams in Finland. The dataset included 92,280 students who completed the matriculation examination in the Helsinki and Turku regions between 2006 and 2020. In total, 156,059 exam performances were analysed. The subjects examined were Finnish language, history and social studies, mathematics, physics, and chemistry, and the results were compared with pollen levels on exam days.
Until now, it has been unclear whether pollen exposure also affects matriculation exam performance. “It is important to recognise that fluctuations in pollen levels can influence learning outcomes and, in the long term, young people’s future opportunities, such as further education, employment, and income,” says Associate Professor Marko Korhonen from the University of Oulu Business School.
Allergic rhinitis—caused by dust, animal dander, mould, and pollen—reduces wellbeing, cardiovascular health, sleep quality, concentration, and mood. Climate change may worsen the situation: longer growing seasons and more favourable conditions increase plant growth and thus pollen production and allergenicity.
Pollen data were obtained from regional pollen samplers maintained by the Department of Biodiversity Sciences at the University of Turku, and exam results from Statistics Finland.
Clear link to poorer exam results
The results showed that exam scores declined significantly when students were exposed to both low and high pollen concentrations compared with days with no pollen. Each increase of 10 pollen grains led to an average decrease of 0.046 points (alder) and 0.245 points (hazel) in exam scores, after adjusting for temperature, air pollution, and rainfall.
Scores in mathematics, physics, and chemistry declined particularly when students were exposed to alder pollen.
The researchers did not know which students were allergic. However, 20% of upper secondary students suffer from allergic rhinitis.
“It is likely that the observed decline in exam performance is mainly due to allergy symptoms among students sensitive to pollen. The decrease in scores would probably have been even greater if only pollen-reactive students had been examined,” says Associate Professor Timo Hugg from the Center for Environmental and Respiratory Health Research at the University of Oulu.
Because matriculation exam results have a significant impact on access to higher education, employment, and income, the researchers emphasise the need to consider pollen effects in exam settings. They suggest, for example, scheduling exams outside the pollen season and ensuring allergy medication is started early. Increasing awareness of pollen exposure and pollen allergies is also important.
“The results indicate that students are not in an equal position when taking exams during the pollen season. This should be taken into account when deciding on the timing of the matriculation examinations,” Hugg notes.
The study was conducted by researchers from the University of Oulu Business School and the Population Health Research Unit at the University of Oulu, together with the Department of Biodiversity Sciences at the University of Turku.
The study is published in the Journal of Epidemiology & Community Health: Timo T Hugg, Janne Lehto, Jouni J K Jaakkola, Simo-Pekka Kiihamäki, Matti Koivuranta, Sanna Pätsi, Annika Saarto, Marko Korhonen: Pollen exposure and matriculation exam performance among students in Finland DOI: https://doi.org/10.1136/jech-2025-224112