Airborne pollen in Funchal city, (Madeira Island, Portugal) - First pollinic calendar and allergic risk assessment.

INTRODUCTION: Nowadays, pollen calendars are useful tools for clinical guidance intended for allergy sufferers, because they can be used to prevent and manage allergic respiratory diseases, thus improving the quality of life.

OBJECTIVES: An aeropalinological study was performed in the city of Funchal with the purpose of establishing a pollen calendar and determining allergic risk, based on a seven year study (2003-2009).

MATERIAL AND METHODS: The airborne pollen monitoring was carried out with a Hirst type volumetric spore trap, following well-established guidelines.

RESULTS: The mean annual pollen index was 1,635.09 and comprised 42 different pollen types. Airborne pollen levels were higher between March - June, accounting for 57.9% of the annual counts. Arboreal pollen grains (52.72%) prevailed in the atmosphere together with herbs and grasses (44.64%), while fern spores (2.29%) and unidentified pollen (0.35%) were scarce. The main pollen types were Urticaceae (20.64%), Poaceae (16.02%), Cupressaceae (13.61%), Pinaceae (9.07%), Myrtaceae (5.93%) and Ericaceae (5.02%). The pollen calendar comprised a total of 14 taxa and is similar to Mediterranean regions, with the exception of Olea europaea, Quercus sp., Betula sp. and Alnus sp. pollen types which are rare or absent. The main pollen season of major pollen taxa is significantly longer in Funchal (on average 239 days) than other European sites, especially for Urticaceae and Poaceae, but the pollen peaks were substantially lower.

CONCLUSIONS: The pollen calendar for Funchal is the first ever created for Madeira region. Taking into account the low pollen index and number of allergy-risk days recorded (39 days in 7 years), the air quality of Funchal can be considered good.