Environmental drivers of the allergenic load caused by Ambrosia artemisiifolia pollen and its major allergen Amb a 1 in the atmosphere.

Understanding the environmental factors influencing the allergenicity of Ambrosia artemisiifolia pollen is crucial for effective allergy prevention. This study, conducted from 2019 to 2022 in Bratislava, Slovakia, utilised a Hirst-type Burkard pollen trap and a Burkard multi-vial cyclone sampler to measure airborne ragweed pollen (by microscopic analysis) and Amb a 1 allergen concentrations (by ELISA), enabling the calculation of pollen allergen potency (PAP). The data analysis showed that annual pollen and allergen levels are affected by meteorological conditions: sunny and dry weather in May accelerated pollen production, while dry conditions in August increased allergenic potency during the main flowering phase. Based on Spearman's correlation analysis, daily allergen levels were significantly associated with pollen concentrations. Regression analysis confirmed the influence of environmental factors on pollen, allergen and PAP levels. Pollen concentration showed a positive association with temperature and wind speed but a negative association with precipitation. Relative humidity was the only meteorological factor negatively linked to allergen levels, while temperature had a negative impact on PAP. The most relevant air pollutants were CO and SO₂, which increased allergen levels and PAP, respectively.