JUANA SUMMERS, HOST:
Some might be able to tell that spring is in the air by the brighter afternoons and the shedding of all those heavy coats.
MARY LOUISE KELLY, HOST:
Others of us have already been alerted by itchy eyes, runny noses and scratchy throats.
SUMMERS: Yep. And if those annoying seasonal allergies feel like they've been intruding earlier and stronger, well, it may not be all in your head.
KELLY: Lew Ziska is an associate professor at the Mailman School for Public Health at Columbia University. He has studied how climate change has affected plant biology for more than 30 years.
LEW ZISKA: As things start earlier in the spring and go longer in the fall because of the warmer weather, that results in a longer pollen season.
SUMMERS: How much longer depends on where you live. In general, the northern U.S. appears to be more affected.
ZISKA: In those areas, we're seeing a substantially longer growing season than we're seeing it in places that are in the southern U.S., sometimes by up to an additional two to three weeks.
SUMMERS: And it's not just that pollen's around for longer - some is more potent.
ZISKA: The thing that makes pollen allergenic are the proteins on the surface of the pollen. And what we found was that the concentration of that particular pollen protein was increasing in the case of two plant species that we know are very allergenic - one is oak, and the other one is ragweed.
SUMMERS: Another factor - carbon dioxide, something plants rely on to grow.
MARY MARGARET JOHNSON: The increasing carbon dioxide concentration stimulates the plant to make more pollen, and it increases the amount of allergic proteins in the pollen itself.
KELLY: That is Mary Margaret Johnson, principal research scientist at Harvard TH Chan School of Public Health. She says extreme weather events, from high winds and thunderstorms to droughts and fires - that they can also exacerbate allergies by spreading pollen farther and wreaking havoc on our respiratory systems.
SUMMERS: And air pollution is yet another factor.
JOHNSON: The pollen itself can attach to particulate matter, kind of acting like a hitchhiker. And so when you inhale the particulate matter, you may be getting more pollen.
SUMMERS: Johnson says while people with pre-existing allergies will suffer more, there may also be some people experiencing pollen allergies for the first time.
KELLY: So for newcomers and veterans alike, here's some tips from Johnson and Ziska to reduce your exposure.
JOHNSON: If you take an antihistamine during pollen season, the recommendation is to start taking it, like, even two weeks earlier than you typically would.
ZISKA: If you have a HEPA filter or ways to try and purify the air in your house, that's also another good strategy to practice. Washing clothes can be good. Sometimes when you're outdoors, you get a lot of pollen on you, and that can stay with you when you go inside.
SUMMERS: And of course, if possible, stay indoors on high-pollen days, even though it might be difficult to resist the lure of all those colorful flowers in the bright sun.
(SOUNDBITE OF GREIG'S "PEER GYNT SUITE NO.1, OP. 46: 1. MORNING MOOD") Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.
