Assessing the Allergenic Load of Tree Species in Kharkiv, Ukraine, Based on Aerial Pollen Survey

Abstract Background Urban landscaping enhances environmental quality but often overlooks the allergenicity of plant species, impacting public health. In Ukraine, pollen monitoring is not systematically regulated. This study aimed to assess the allergenic load of tree species in Kharkiv, Ukraine, based on aerial pollen surveys, and to identify the most allergenic species and peak periods of pollen emission. Methods From March to June 2024, aerial pollen samples were collected in the Novobavarskyi and Saltivskyi districts of Kharkiv using the gravimetric Durham method at 1.5-m and 15-m height. Pollen grains from woody plant species were identified and quantified. Potential allergenicity was assessed through the CARE-S index, which considers immunogenicity, morphology, and pollen production characteristics. The newly proposed Total Pollen Allergenic Load Index (PL) allowed us to identify periods of high allergenic risk. Results The survey detected pollen from 16 tree species, with Betula pendula, Pinus sylvestris, Corylus avellana , and Juniperus sabina showing the highest allergenicity. The integrated PL effectively reflected the cumulative allergenic potential of the airborne pollen spectrum, allowing identification of distinct seasonal peaks. The highest pollen deposition and allergenic loads were recorded between May 5 and May 15, when 8 tree species released pollen simultaneously, 2 of which— B. pendula and P. sylvestris —contributed most to the total allergenic load. Conclusions Several indigenous and introduced tree species in Kharkiv contribute significantly to airborne allergenic loads. Regular monitoring using volumetric methods is necessary to create reliable pollen calendars and guide safer urban landscaping practices, ultimately improving public health outcomes.