By - Dr. Massoud Mahmoudi

Trees, grasses and weeds are outdoor allergens. The abundance of pollens depends on the geographic locations and the time of the year. The climate variation of each region and its altitude from the sea, among other factors, differentiate one from another.

There are also these variables:

• Time of the year. Each region has a different pollinating season.

• Abundance. To cause allergic symptoms, pollens need to be airborne. Repeated inhalation of the same pollens over several seasons can cause an allergic condition in susceptible individuals.

• Pollen transportation. Allergenic pollens are usually windborne, whereas insects transport pollens of plants with colorful flowers. Therefore, such plants are not the usual source of pollen allergy.

• Size of pollens. Smaller pollens can reach lower airways whereas larger pollens may not, or at least not efficiently. Pollen allergy symptoms may vary depending on the site of pollen exposure. The majority of the pollens are larger particles that can reach the eyes, nose and the upper airways where they cause symptoms.

Tips to deal with outdoor pollen allergy:

• Close windows. This helps prevent transportation of airborne pollens to indoor environments.

• Do not mow the lawn yourself. If you must mow, wear a mask. Change your clothes and take a shower afterward.

• Change outdoor clothes. After playing outside, children should change their clothes and take showers to remove contaminated pollens from their hair and bodies.

• Stay indoors. Stay indoors during days with high pollen counts.