Monitoring techniques for pollen allergy risk assessment.

Understanding airborne pollen allergens trends is of great importance for the high prevalence and the socio-economic impact that pollen-related respiratory diseases have on a global scale. Pursuing this aim, aeropalynology evolved as a broad and complex field, that requires multidisciplinary knowledge covering the molecular identity of pollen allergens, the nature of allergen-bearing particles (pollen grains, pollen sub-particles, and small airborne particles), and the distribution of their sources. To estimate the health hazard that urban vegetation and atmospheric pollen concentrations pose to allergic subjects, it is pivotal to develop efficient and rapid monitoring systems and reliable allergic risk indices. Here, we review different pollen allergens monitoring approaches, classifying them into I) vegetation-based, II) pollen-based, and III) allergen-based, and underlining their advantages and limits. Finally, we discuss the outstanding issues and directions for future research that will further clarify our understanding of pollen aeroallergens dynamics and allergen avoidance strategies.

Temporal variation of allergenic potential in urban parks during the vegetation period: a case study from Bratislava, Slovakia.

Park greenery represents an oasis for urban residents; however, during the flowering period of trees that produce allergenic pollen grains, these areas threaten individuals suffering from seasonal allergic respiratory diseases. In this study, we evaluated the temporal distribution of the allergenic potential of three most important urban parks in Bratislava over the vegetation period, using a modification of the Urban Green Zone Allergenicity Index (IUGZA) and Individual-Specific Allergenic Potential Index (IISA) designed as a running index - rIUGZA and rIISA. We found that rIUGZA gives better information for park management and revitalization, since it considers the potential size of woody plants, while rIISA, considering the actual size of the vegetation, provides more relevant information for pollen-allergy sufferers. Based on rIISA, the allergenic potential was highest in May for the Grassalkovich Garden (formal baroque garden) and Janko Král Park (English landscape park) and in April for the Medic Garden (repurposed baroque garden). We also found differences in the duration of the period of increased allergenic potential in these parks, ranging from 1 to 3 months. Based on the total annual sums of rIISA, we found the highest allergenic potential in the Medic Garden and lowest in the Janko Král Park. This variance is caused mainly by the different density of trees and percentage of allergenic species. The biggest contributors to the allergenic potential were Platanus, Acer and Tilia. Based on the information on temporal variation of the allergenic potential during the vegetation period provided by the running indices, it is possible to improve the planning of park revitalization based on the flowering period of allergenic species and provide better information to the pollen-allergy sufferers for minimizing the allergenic effect of urban green areas on their health during a particular month.

Tourist risk assessment of pollen allergy in tourism attractions: A case study in the Summer Palace, Beijing, China.

Pollen allergy has already been an increasingly prominent ecosystem disservice in tourism attractions. However, few studies have assessed the tourist risk of pollen allergy through integrating multidisciplinary knowledge of ecology, medicine, phenology, and risk management. Basing on the conceptual framework of risk assessment proposed by UNISDR, we first established an index system of pollen-allergy risk for tourists in attractions and outlined assessment methods 18 available indexes were put forward to cover three aspects: hazard of plant allergen, tourist vulnerability, and resilience of assessment units. Subsequently, taking the Summer Palace as the case study area, we conducted a tourist risk assessment of pollen allergy. Values of nine available indexes were obtained via ecological investigation, phenological observation, and data mining of visitors' logs on Sina Weibo. Risk levels of spring pollen allergy for tourists in different assessment units were revealed by combining the green zone allergenicity index model and three-dimensional risk assessment matrix. The results showed that: (1) There were seven primary pollen-allergenic plants in the Summer Palace, including Platycladus orientalis, Sabina chinensis, Salix babylonica, Pinus tabulaeformis, Populus tomentosa Carr, Morus alba L. and Fraxinus chinesis, among which Platycladus orientalis and Salix babylonica were the highest allergenic. (2) Among 18 spots, tourists faced the highest risk level of pollen allergy in spring at three spots, namely the Hall of Serenity, Hall of Benevolence and Longevity, and Gallery of Literary and Prosperity. (3) The two routes of the Long Corridor and Longevity Hill scored high on the risk level. (4) Among four areas, risk levels of the Front-hill and Rear-hill areas were high. Given the increasing spatial-temporal uncertainty of pollen allergy and tourist behaviors under global warming and urbanization, the related monitoring should be strengthened in the future. Furthermore, the dynamic and improved assessment of pollen-allergy risk should be institutionalized and be integrated into the evaluation of tourism experience quality. Tourism administration should make full use of relevant assessment results and conduct more effective risk communication.