Pollen Sized For A Special Job - What You Can Do To Help Yourself: Allergies

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Pollen: Sized for a special job

Pollen: Sized for a special job

Pollen — the male cells of flowering plants, grasses, weeds, and trees — is essential for fertilization. Nature has designed pollen to be small, dry, and light so it can be carried by the wind. As well as doing an excellent fertilizing job, pollen is responsible for hay fever in about 35 million Americans. Because pollen is ubiquitous, you may find medication is necessary, but avoidance can lessen the severity and frequency of your symptoms. Many people, for instance, like to get a jump-start on their pollen-laden day by checking pollen counts given out by the media.

Pollen counts, which include mold spore counts, can be of some help — if you know how to interpret them. But keep in mind that the pollen reports in the media are one or more days old. In that sense, the pollen count is yesterday’s news — a record of what was, not what is to come. To obtain a pollen count, officials wait for the grains to float down and settle so they can be counted. By the time the results are reported, the amount of pollen in the air may have changed.

A number of institutions such as universities and medical centers have certified counters. The institutions pass on the count to the media on a volunteer basis. Several factors can affect the count. Weather is very important. On rainy, windless, or cold days, there is less pollen on the move compared with hot, dry, or windy days. Where the pollen is collected matters, as does the time of day. Is it collected in an urban area where there are fewer trees and flowering plants? Is it collected between the hours of 5 a.m. and 10 a.m., prime pollen time when more pollen is in the air? What type of device was used to obtain the count? At any one time in a given location, these factors can cause considerable variability in the count. They also account for the variability within a geographic region on any one day.

The AAAAI has certified the National Allergy Bureau (NAB), a reliable free service that obtains pollen and mold counts from certified collectors nationwide and passes on the data to the media several times a week.

Pollen counts may fluctuate depending on the circumstances, but fortunately trees and plants are very consistent. In the Northeast, the pollen season starts in February or March and ends in October. In southern states it starts earlier and ends later, so that grasses may pollinate for 10 months in Florida. In Northern climes, trees kick off the season, followed by grasses, and finally weeds. The Allergy Report of the AAAAI has maps of the geographical and seasonal distribution of pollens, which may be accessed online.

Tips for avoiding pollen exposure

Here are some ways to minimize your pollen exposure:

• Stay indoors when the pollen count is high, especially on dry, windy days.

• Stay indoors between 5 a.m. and 10 a.m., when airborne pollen is likely to be at its highest each day.

• Keep home windows closed at night, and turn on the air conditioner.

• Keep car windows closed when driving.

• Vacation at the coast during high pollen season.

• Don’t cut your grass; have someone else do it.

• Don’t hang clothing and bedding out to dry.

People who are very bothered by airborne allergens may wonder if moving to another part of the country would make a difference. The answer is yes and no. In the short term, you can outrun your allergens and find temporary relief in the company of other pollens. But this relief is usually short-lived. Eventually, you are likely to develop a hypersensitivity to the pollens in your new locale and become subject to allergic attacks once more. You can run but you can’t hide! Relocation isn’t ultimately a solution. An exception is to go up in the world. Higher altitudes, where there is less pollen of any sort, can be beneficial. Interestingly, some former tuberculosis sanatoriums, built high up, are now asthma centers.

Last updated:	August 21, 2006
Reviewed By:	Faculty of Harvard Medical School