Assessing pollinosis risk in the Vesuvius National Park: A novel approach for Index of Urban Green Zones Allergenicity

Pollen released by urban flora is the mayor contributor to airborne allergen content, with adverse impact on human health, representing one of the main ecosystems disservices. The Vesuvius National Park (Southern Italy) develops on an area of 8017 ha, falling within thirteen municipalities, in which 345,000 people live. Pollination events in the park may pose a threat to the health of people damaging their well-being. The objective of this work is to establish the potential allergenic value of the plant species occurring in the Vesuvius National Park, so that the allergenicity of the park can be estimated through version novel approach for Index of Urban Green Zones Allergenicity (modI_UGZA). It allows the determination of allergenicity of extended areas, by using sampling area and subsequent estimation of plant covers with Braun-Blanquet scale. Sampling areas have been defined and phytosociological surveys have been conducted to register plant species, relative covers and allergenicity potential. As a weighting factor, the surfaces of the park total area, and municipalities' areas were used. First, we obtained the results by the traditional deterministic approach. The results indicated that an allergic risk cannot be excluded for Ottaviano municipality and the whole park. Subsequently, we developed a quantitative risk assessment model for allergenic risk based on probabilistic model resulting in a more exhaustive risk assessment. There is a 5% probability that in the Vesuvius National Park, the vegetation may rise to an allergenic risk. The municipality-level probabilistic risk outcomes also reveal a certain probability of risk even for eleven municipalities. Sensitivity analysis indicate that plant height and vegetation cover mainly affect expected risk. This tool may be useful to forecast and prevent pollinosis related events on a large scale, allowing risk mitigation measure in health protection perspective.