Objective: Pollen grains belonging to some plants have an important place among aeroallergens that present in the air and cause allergies by entering the body via the respiratory tract. These include Betula (birch - birch tree) pollen belonging to the family of Betulaceae.

Materials and Methods: In this study, we reviewed studies on the monthly variation and annual proportions of Betula pollen in 51 different regions in Turkey with the volumetric method using a Lanzoni/Burkard sampler or with the gravimetric method using a Durham sampler together with the daily distribution of Betula pollen in m3 air in Bursa province in 2012. Furthermore, the authors reviewed studies on Betula pollen sensitivities in Europe and our country.

Results: According to the atmospheric pollen studies, Birch tree pollen was found in the air for 3-5 months at many centers. It was most intensely observed in March-April. A total of 454 birch pollens were found in m3 air in 2012 in Bursa. The birch tree main pollen season lasted 86 days and birch pollen grains were most intensely encountered in March.

Conclusion: Symptoms can develop in people who are sensitive to birch tree pollen in the spring due to widespread planting for decorative purposes especially in parks and gardens and along the streets in recent years and the resultant production of large amounts of pollen, especially in April and May. In addition, it must not forgotten that some food allergies of vegetable origin (oral allergy syndrome) can be accompanied by pollen allergy in these individuals.