Airborne pollen is so light that air currents can carry it hundreds of miles from its source.

But remember that airborne pollens can travel hundreds of miles from where they originated.

In some cases, symptoms are temporary, possibly related to outdoor conditions like airborne pollen.

"We all have to breathe, so we can't keep from inhaling airborne pollen."

The worst times for airborne pollen are on days that are warm, dry and breezy.

Finally, cross-reactive allergens have been identified among certain foods and airborne pollens.

Even if pollution is low, airborne pollen and mold can make a trip outdoors particularly daunting for people with respiratory conditions.

And changing the filter on a window-unit air conditioner is as effective a guard against airborne pollens.

Hay fever is the common name for an allergic reaction to some airborne pollens that circulate in spring, summer and early fall.

Airborne pollen from blooming trees hits the eyes and nose of many spring allergy sufferers, she said.

Although only 8 to 10 percent of the population is allergic to airborne pollen, no one can afford to assume he or she has escaped indefinitely.

Airborne pollen.

Offending plants like oak trees, grasses and Ambrosia - better known as ragweed - have inconspicuous flowers and airborne pollen.

Only nonflowering trees use airborne pollen for fertilization, since flowering plants rely on bees and other insects as pollen messengers.

Dr. McNally and her group concluded that cosmetic lip hair - handlebar or brush - may be a reservoir of airborne pollen grains.

Aerobiologists have traditionally been involved in the measurement and reporting of airborne pollen and fungal spores as a service to allergy sufferers (Larsson, 1993).

"It's a super marketing tool," said Michael Diamond, a Daytona Beach, Fla., allergist who attended a recent workshop on identification of airborne pollen and fungus spores at the academy's annual convention held last month in Baltimore.

By studying the pollen in a sample of honey, it is possible to gain evidence of the geographical location and genus of the plants that the honey bees visited, although honey may also contain airborne pollens from anemophilous plants, spores, and dust due to attraction by the electrostatic charge of bees.