Pollution is everywhere:on our roads, in the surrounding air, and even in our homes. Exposure to pollutants is responsible for many respiratory and cardiovascular diseases, as well as certain cancers. Fine particles, combustion gases, pollens, moulds:where does indoor and outdoor pollution come from? What are the risks associated with pollution?
Various chemical, physical and biological agents are responsible for outdoor air pollution. Some result from a direct emission into the air, others are formed as a result of chemical reactions between pollutants. Their high concentrations are often reported in the media during pollution peaks .
Road infrastructure emits a large amount of pollutants into the outdoor air.
Gases and particles come from vehicle exhausts, their air conditioning systems, but also from the wear of tires and the road, and that of brakes and clutches. These are so-called "primary" pollutants , that is to say, they are emitted directly into the air we breathe. We find:
Road traffic also generates so-called “secondary” pollutants , which it is impossible to filter since they are formed after chemical reactions between primary pollutants. We find:
Summer temperatures favor the production of ozone.
Residential wood and coal heating is a source of fine particle emissions suspended in the outdoor air. While this method of heating has tended to decline in France since the 1990s, the combustion of wood remains the main source of fine particle emissions during certain winter periods at very low temperatures.
Among the fine particles released, we find soot carbon, but also polluting gases such as carbon monoxide (CO), nitrogen oxides (NOx), aromatic hydrocarbons, volatile organic compounds, toxic metallic elements.
Pollens are biological air pollutants since they can have a negative impact on health. These microscopic plant particles are said to be allergens. It is the anemophilous pollens, that is to say pollens transported by the wind, which are the most aggressive. There is a pollen calendar according to the regions. The dissemination of pollen depends on the seasons:
If the dry weather favors the dissemination of pollen by the wind, the rain on the contrary flattens the pollen on the ground.
Indoor pollution is often overlooked but it is even more concentrated than outdoors. At home or at work, 80% of our time is spent indoors!
Among the chemical pollutants of the house, there are many particles and gases generated by road traffic and by heating systems:nitrogen oxides, volatile organic compounds, ozone... There are also pollutants intimately linked to our habitats. :
Homes concentrate maximum pollution during the winter:it is during this season that the heating is running at full speed and there is the least ventilation.
Biological pollutants are numerous inside our homes. These are allergens that have an impact on the respiratory tract. We find in particular:
Pollution is a real danger for the whole population. Some people are even more sensitive:children, pregnant women, the elderly, and people suffering from cardiovascular or bronchopulmonary diseases. Continuous exposure to a high level of pollution is particularly risky for health.
Pollution causes many complications on the respiratory, cardiac and vascular systems. Asthma is an instructive example:the number of people with asthma has doubled in just 10 years and affects 10% of children. COPD , or chronic obstructive pulmonary disease, is a progressive respiratory disease. The inflammation of the bronchi that characterizes this pathology is directly linked to the inhalation of allergenic substances, especially tobacco.
Respiratory allergies , which are also increasingly common, are caused by allergens and aggravated by chemical and physical pollutants. To learn more about respiratory allergies, you can read our article "Respiratory allergy, a daily annoyance".
Polluting particles weaken the respiratory mucous membranes which no longer play their role as a barrier. They become more easily permeable to toxic and infectious agents (viruses, bacteria, fungi).
Inflammation by fine particles can thus affect the blood vessels, then, through longer-term exposure, eventually harms heart function.
Some volatile organic compounds are even responsible for degradation of renal, hepatic, digestive, or nervous functions, and teratogenicity, that is to say, they can induce abnormalities in the fetus.
It is by analyzing the links between pollution and the various cancers that the International Agency for Research against Cancer (IARC) has been able to issue clear-cut opinions. The onset of lung cancer is very closely linked to exposure to polluting particles, whether tobacco or air pollution in general. A clear correlation also exists between bladder cancer and exposure to fine particles.
In more general terms, outdoor pollution as a whole has been classified as a "certain carcinogen" by the research body. Pollution is now considered the most common environmental cause of cancer in the world.
Fighting against the main sources of pollution in homes is within everyone's reach, and helps reduce the risk of allergies:
Outside, it is preferable to walk or play sports away from the main roads. Parks in cities are a perfect place. It's also the perfect place to take baby for a walk! Did you know that the ASEF (Association Santé Environnement France) has shown that children in strollers were, in the low position, much more exposed than adults to fine particles and exhaust gases? According to the Air Lorraine Association, it is best to use a baby carrier to keep the child away from the exhausts.
Throughout the day, many particles can be deposited on the surface of the respiratory mucous membranes. The daily use of a nasal spray with isotonic seawater helps to remove the polluting and allergenic particles accumulated on the nasal mucous membranes. Similarly, eyewashing is a reflex that can prove to be life-saving in the event of tingling, whether it is carried out with specific adapted solutions or with physiological saline. To learn more, you can watch our video on daily nasal hygiene, and read our article on the fight against eye strain.
