Trees in cities exacerbate hay fever than in rural areas because air pollution spreads pollen, the study says.
It was already known that fine particles of dust and car exhaust help disperse pollen by sticking to it, making it stay in the air longer and more likely to get into our eyes, nose and throat.
As tree pollen season begins in the coming days, the researchers found that pollution also increases the effectiveness of the pollen, making allergic reactions more likely.
The increase in “allergenicity” is due to pollution causing trees to release “stress proteins”, also called defense proteins. They protect them from viruses, bacteria and other invaders such as dirt particles.
The researchers found that one of the defenses created is a particularly potent allergen found in birch pollen, known as Bet v1, which was found in “significantly higher” amounts in polluted areas than in less polluted ones.
The study was done on drooping birches in Poland, but the results apply to other trees that commonly cause hay fever, such as alder, birch, hazel and horse chestnut.
Tree pollen, which causes hay fever, is usually shed in early February, and the season usually lasts until June.
And pollution could potentially have the same effect on grass, which has hay fever season from June to September, and weeds (May to July), and increase the impact of these allergies, though this remains to be determined.
“We found that urbanization and air pollution can affect the function of proteins by changing their structure. This can lead to an increase in their allergenicity and a more frequent occurrence of allergies in sensitized people, ”says Monika Zemyanin from the Faculty of Medicine of the Jagiellonian University in Poland.
“The results may explain treatment errors for people with pollen allergies living in polluted areas. Also, when planning green space in cities, allergenic trees should not be planted, as they produce more stress proteins with higher allergenic potential,” she added.
Air pollution is also increasing hay fever in the city in other ways, according to Margaret Kelman, deputy director of clinical services for Allergy UK.
“Urbanization and air pollution increase the amount of carbon dioxide in the atmosphere, which negatively impacts the ability of the immune system to fight infection and can contribute to worsening allergy symptoms,” she said.
Research published in the journal PLUS ONE.
Allergy UK tips for reducing tree pollen exposure:
Keep an eye on the pollen forecast every day and try to stay at home on days with a lot of pollen. Rain washes pollen out of the air, so pollen counts should be lower on cooler, rainier days. Caution should also be exercised during thunderstorms, especially when pollen levels are high. If you have hay fever and asthma, these weather conditions can cause even mild symptoms to become severe. Therefore, it is important to be prepared and take allergy medications regularly to keep symptoms under control. If symptoms worsen, seek medical attention.
If staying indoors on high pollen days is not an option, the following measures can help reduce exposure:
- Wear a mask, wraparound sunglasses, and a hat with a large peak or visor when you’re outdoors to protect your eyes, face, and hair from pollen allergens.
- If you’ve been outside for a long time, take a shower, wash your hair, and change your clothes, especially before bed. Because pollen is virtually indestructible, when not wet, it remains on the hair, body, and clothing, acting as a constant source of allergens that cause hay fever symptoms.
- Avoid outdoor activities that expose you to pollen, such as lawn mowing or leaf raking.
- Keep windows closed at home and in your car. The most important are the early morning and evening hours, when the amount of pollen is higher.
- Avoid drying clothes/bedding outdoors as pollen can get on clothes.
- Wipe your pet’s fur with a damp microfiber cloth to remove pollen after they’ve been outside.
Source: I News
I’m Raymond Molina, a professional writer and journalist with over 5 years of experience in the media industry. I currently work for 24 News Reporters, where I write for the health section of their news website. In my role, I am responsible for researching and writing stories on current health trends and issues. My articles are often seen as thought-provoking pieces that provide valuable insight into the state of society’s wellbeing.