Respiratory allergies concern 25 to 30% of French people, or nearly one in four people. They appear as soon as the immune system comes into contact with an allergen present in the air or the environment, such as pollens, dust mites, molds or animal dander, which cause inflammation of the mucous membranes eyes, nose, throat and even lungs and triggers the production of targeted antibodies against the allergen in question.
Result ? A series of unpleasant symptoms to say the least: sneezing, watery eyes, runny nose or congestion, itching in the eyes, nose and throat, allergic cough, even breathing difficulties. And as if that weren’t enough, air pollution greatly exacerbates these symptoms. Insights from Dr Jean-Marie Nguyen, allergist at Bicêtre Hospital and member of the association Asthma and Allergies.
Is it possible to be allergic to polluted air?
It is not not possible to be allergic to polluted air as such. On the other hand, pollution can be an aggravating factor of allergy, indicates the specialist. And to explain: “allergy is a specific response of the immune system to an irritating substance perceived as dangerous by our body (an allergen). It is mediated by specific antibodies, immunoglobulins E (IgE)”. Pollution is direct chemical attack : our body does not really create anti-pollution antibodies.
In summary, we are not allergic to pollution. This causes inflammation in the mucous membranes, but most often this reaction is not linked to an immune reaction, insists Dr. Nguyen.
Also, some people may be more sensitive to air pollution than others because of their age and state of health. Children, the elderly and those with respiratory or cardiovascular conditions are particularly more likely to experience negative effects from air pollution.
What is the impact of pollution on respiratory allergies (pollen, mites, animals, etc.)?
Air pollution aggravates pollen allergies for several reasons:
Pollution changes the structure of pollens
Some chemical pollutants, including ozone (O3), sulfur dioxide (SO2) and nitrogen dioxide (NO2), are capable of deforming and fracturing the wall of pollen seeds. In fact, pollen grain fragments can penetrate much deeper into our airways.
In addition, some chemical pollutants are capable of modify the structure of pollen proteins or of attach directly to pollenwhich then become much more allergenic.
Pollution weakens our mucous membranes
As noted above, pollution irritates the mucous membranes of the eyes, nose, throat — and sometimes our lungs. Our airways are weakened and more sensitive to the various allergens present in our environment and our immune defenses may be slightly less efficient. In fact, people with allergies are more vulnerable during pollution peaks.
Good to know: the role of global warming is also regularly singled out. With rising temperatures, pollens are produced and released in greater numbers, which increases the risk of allergies. Not to mention that the pollination season is likely to be longer and longer.
What impact on cross allergies?
“A priori, pollution does not directly promote the development of cross allergies. On the other hand, our way of life and our new environment (biotope) will probably make us more and more sensitive to cross allergies between food and pollen. Digestive and respiratory intolerances are more and more numerous and precocious : Previously, cross allergies between birch pollen and certain foods such as apples and hazelnuts, for example, were triggered after a few years. Today, some children are diagnosed with cross allergies from the age of 7. And it is currently impossible to know if this phenomenon is linked to the pollution itself, to our food or to our global environment”, answers Dr Nguyen.
Fine particles, carbon monoxide, sulfur dioxide… What are the most problematic air pollutants?
The air we breathe is made up of approximately 78% nitrogen, 21% oxygen and 1% noble gases as argon, neon, krypton, xenon or even helium. Pollutants represent less than 0.05% of the composition of the air, but can have a significant impact on our health and the environment.
Some pollutants are natural, such as dust emitted during volcanic eruptions, but the vast majority of pollutants are the result of human activity. However, we distinguish primary anthropogenic pollutants, directly from road traffic, industries, heating, agriculture, etc. :
- hydrocarbons;
- fine particles;
- sulfur dioxide (SO2) ;
- THE nitrogen oxides (NOx), which include nitric oxide (NO) and nitrogen dioxide (NO2);
- volatile organic compounds (VOC), such as benzene, acetone or perchlorethylene;
- et some heavy metalssuch as lead and cadmium.
As to secondary anthropogenic pollutants, they are created in the atmosphere as a result of chemical reactions between pollutants. We note in particular l’ozone, nitrogen dioxideet ultrafine particles.
Indoor pollution can also play tricks on us!
“Peaks of outdoor pollution can wreak havoc. But we too often forget that we also find many pollutants in our interiors“, underlines Dr. Nguyen. The sources of pollution are not the same, but they can all the same have serious consequences on our health. In question:
- the cigarette smoke ;
- THE household products ;
- the dust and thehumidity ;
- THE combustion appliances ;
- THE pets ;
- THE carpets and coverings ;
- THE scented candles and the essential oils ;
- etc.
What other illnesses are linked to air pollution?
Allergy sufferers are not the only dependents on air pollution. Other conditions can also be aggravated by exposure to poor air quality:
- certain respiratory conditions such as asthmaand emphysemaa chronic obstructive pulmonary disease (BPCO), etc. ;
- certain heart conditions such asangina ;
- certain chronic diseases such as diabetes ;
- etc.
Furthermore, the pregnant womenTHE young childrenTHE the elderlythe people who often work outdoors or who regularly exercise outdoors may be more sensitive to allergens.
What solutions to avoid the deleterious impact of pollution when you are allergic?
Several solutions can relieve allergic symptoms. In parallel with the measures of eviction, it is essential to clean its mucous membranes.
Protect yourself from indoor and outdoor pollution:
In case of characteristic symptoms, start by consulting an allergist who can identify the allergens to which you are sensitive. Then put these few measures in place:
- ventilate your interior every day;
- go there regularly the vacuum cleaner ;
- avoid animals to which you are allergic;
- avoid them dry and hot environments which accentuate the dry throat effect and therefore the cough;
- do not smoke and do not expose yourself to cigarette smoke;
- wash regularly interior textiles, carpets, curtains, soft toys for children, etc. ;
- favor dust mite mattresses and pillows ;
- avoid home fragrances (candles, in aerosols, automatic or electric perfume diffuser, etc.);
And in case of pollen allergy:
- close your windows during the dayventilate your accommodation only in the evening, but avoid sleeping with the window open;
- limit outdoor activities (walks, camping, picnics, etc.) when the pollen concentration is highest (usually in the early morning and evening);
- by car, roll up the windows closed and, if possible, use a recirculated air system;
- avoid physical exertion and outdoor sports during pollution peaks;
- wear a hat and sunglasses outdoors (to prevent pollen or stinging fruit hairs from coming into contact with your eyes);
- avoid drying your laundry outside and clean your clothes regularly to get rid of any pollen;
- wash your hair regularly to remove pollen (preferably before going to bed);
- choose single-use contact lenses (disposable at the end of the day), rather than monthly or fortnightly lenses;
- and keep up to date with the pollen alerts from RNSA (National Aerobiological Surveillance Network).
Relieve allergy symptoms
A few simple actions can relieve allergic symptoms:
If the symptoms persist or worsen — and seriously handicap you — see your doctor!
To find out more about respiratory allergies, visit the association’s website Asthma & Allergies. Its main objectives? Inform and support asthmatic or allergic patients, parents, as well as doctors and health professionals. You can also contact their green number: 0800 19 20 21 (free call).