An allergenic pollen calendar for Malta : a desk-based approach

Abstract

The study of airborne pollen and its concentration in the atmosphere is essential for the diagnosis, testing, treatment, and prevention of pollen allergies. Pollen calendars are a tool used to display the concentrations and pollination seasons of various pollen types in the atmosphere throughout the year. The prevalence of pollen allergies is shown to be increasing, prompting more aerobiological studies to be conducted throughout Europe. However, Malta does not yet have a published pollen calendar or a continuous pollen monitoring system. Fourteen pollen calendars from different Mediterranean countries were analyzed to determine the main pollen season, season length, peak pollen concentrations, annual pollen index, and allergenicity for the most abundant pollen taxa in the atmosphere. A proposed pollen calendar for Malta was created with the top 10 allergens being: Olea europaea, Poaceae, Chenopodiaceae/Amaranthaceae, Urticaceae, Cupressaceae, Plantaginaceae, Quercus, Euphorbiaceae, Asteraceae, and Pinus. A five-day mini study was conducted using a personal Burkard sampler to assess the feasibility of using a personal sampler to obtain data rather than a continuous monitoring system. 19 pollen grains belonging to seven taxa were identified: Amaranthaceae, Cupressaceae, Euphorbiaceae, Mercurialis annua, Poaceae, Solanaceae, and Urticaceae. 212 fungal spores were counted, and 17 taxa were identified using microscopy. The three most prevalent fungal spores during this five-day study were Cladosporium (2,977.46 spores/m³), Alternaria (355.52 spores/m³), and Aspergillus/Penicillium (444.4 spores/m³). Continuous aerobiology monitoring could help protect individuals from allergic risk by informing individuals of the pollen types and concentrations present in the atmospheres and by providing urban planners with data on what vegetation to avoid planting in urban spaces.