Scientists are unraveling the link between pollution and psoriasis
Maharashtra, India – When Babytai Suryavanshi first noticed a few scaly patches on her right forearm, she ignored them for three months, thinking that it was an infection that would heal alone.
While working in the fields of Sorghum last year, she noticed that the patches had become higher and red and that they burned.
What Suryavanshi, 76, did not know, and what researchers discover now is that air pollution can play a role in the trigger and worsening of this disease.
Around 99% of the world’s population is exposed to tunes that do not respond to the air quality guidelines of the World Health Organization. And in 2021, 42.98 million people had a case diagnosed with psoriasis. But studies suggest that many people can be in part in part because it is easily confused with other conditions and more difficult to locate on darker skin tones; Some estimates suggest 125 million people are affected worldwide.
For Suryavanshi, the link between his condition of skin and pollution became clear after the doctor asked him to pay attention to his environment. For more than 30 years, she worked in a sugar cane plantation nursery near her house Hammi village in Western India. She left last year because the constant smoke in the combustion of sugar cane residues and plastic sowing sets triggered repeated escapes, she said. Now she works on farms, but this also has risks because neighboring factories often expose her to polluted air.
An emerging link
Atmospheric pollution is a term that encompasses a wide variety of chemicals and particles that humans spit in air through industrial activities, from factories to driving cars. It can encompass everything, from forest fire smoke to smog. It contains fine particles of different sizes – including PM2.5, which is less than 2.5 micrometers (PM2.5) and PM10, less than 10 micrometers – as well as chemicals such as nitrogen dioxide (NO2) and nitrogen oxides (NOX).
Psoriasis, on the other hand, is an autoimmune condition in which the immune system attacks the body’s own tissue, namely skin cells. People generally have escapes from the disease, which are treated with creams, phototherapy or drugs that calm the immune response. The condition tends to operate in families, so there is a genetic component It makes people more vulnerable.
But genes are not the only factor in play. The link between psoriasis and pollution has been found in several studies from around the world.
For example, an analysis included nearly 285,000 people from British Biobank, a benchmark for health data and biological samples from British adults, which were followed for 15 years. He revealed that in the long term Exposure to pollution can accelerate biological aging. They measured this aging using PhenoAge algorithm, a tool known as “aging clock“This considers the biological age of the body, rather than the simple number of years. This estimate indicates whether the body is aging more quickly or slower than a medium and healthy basic line, and can also predict the risk of death of any cause or incidence of age -related diseases, such as cancer.
The increase in this aging metric was linked to an increased risk of psoriasis, each increase of one year of the biological age linked to a risk of 5% of the condition.
Another study, from Verona, Italy, found a temporal link between High pollution days and escape from psoriasis. The study followed the levels of pollution in the city in the days preceding patients visiting the clinic to obtain treatment for psoriasis, taking an average of the pollution levels in the previous 60 days. The results have shown that high exposure to air pollution within this period, defined as passing a certain threshold of PM2.5 and PM10, increased the chances of visits to these thrusts.
In addition, a 2024 Study Of more than 3,600 Americans have studied the relationship between psoriasis and urinary metabolites of polycyclic aromatic hydrocarbon (HAP), components of air pollution formed during the combustion of coal and petroleum, garbage and other carbon -based substances. People with higher pah metabolite levels – indicating higher exposure in recent days – were 83% more likely to have psoriasis. Another study based in the United States, published in 2023, linked Clinical visits for psoriasis with pollution caused by forest smoke.
Even short pollution points can increase the risk of medical visits related to psoriasis. A five -year assessment in Nanchang, China, examined the levels of several pollutants, including nitrogen dioxide and carbon monoxide, and found a linear relationship between increases Levels of pollutants and visits related to psoriasis at the doctor. The increased degree of risk and the gap between exposure and an ambulatory visit varied according to the measurement of specific pollutants, but the gap was generally a few days a week.
Causes an effort
These studies indicate a kind of link between pollution and psoriasis, but scientists deepen exactly the way in which polluted air triggers or aggravates the condition. And the responses, although complex, are starting to emerge.
Some studies suggest that small pollution particles can directly damage the barrier outside the body, disturbing the skin both physically and chemically, Dr Nidhi SinghAn environmental epidemiologist and postdoctoral researcher at the IUF – Leibniz Research Institute for Environmental Medicine in Germany, told Live Science in an email.
For example, fine particles have been shown to cause changes to proteins and fats in the skin, said Singh, who wrote an article on Genetic and environmental risk factors For psoriasis. These changes can disrupt enzymes from the body of antioxidant defense of the body, which cleanses tissue damage caused by free radicals, such as reactive oxygen and nitrogen species. It is also possible that air pollution feeds the production of reactive nitrogen species in human tissues, especially in the skin, added Singh.
Dr Paolo GisondiAssociate professor of dermatology at the University of Verona who co-wrote the Italian study, told Live Science that if the exact biological mechanism is not entirely understood, “we can speculate that air pollutants trigger inflammation in the skin by activating immune cells and stimulating the release of inflammatory molecules”. This abnormal immune activation can then lead to psoriasis.
Singh has also noted that, in laboratory dishes with stem cells that develop in skin cells, ultrafine particles – the smallest component of air pollution measuring less than 0.1 micrometer – can increase the Activity of genes associated with inflammation and psoriasis. In laboratory dishes, ultrafine particles can also disrupt the normal development of keratinocytes, the main cells of the external skin layer.
An article published this year has examined the British Biobank data and identified a specific gene This can be involved in the mechanism: Zmizi. This gene generally helps to regulate the immune system and inflammation and air pollution are linked to changes in its activity. ZMIZ1 acts like a dial, refined inflammation levels. However, air pollution can maintain this locked dial in the “high” position, which increases inflammation and increase the probability of autoimmune diseases such as psoriasis, the study revealed.
What can we do?
At the individual level, people can reduce their exposure to pollution by staying inside on high pollution days and using air purifiersSaid Singh. And if they have to go out, they can try to limit the number of these small particles penetrate their follicles for the skin and the battery by covering the parts of the body exposed with protective clothes. They can also clean or exfoliate regularly with products that eliminate the accumulation of skin particles, added Singh.
But Singh highlighted the need for wider regulatory action. In addition to adopting rules that reduce air pollution, governments should develop stronger early alert systems for high pollution days, which can help people know when staying inside.
For residents like Suryavanshi, taking measures to avoid its psoriasis triggers is difficult.
There are more than 100 small and large sugar cane nurseries in their village, each produces pollution, she said. Like others in its neighborhood, it also heats water to swim every day on a wood stove, which exposes it to additional smoke pollution.
Last month, her husband, Mahadev Suryavanshi, 78, also received a diagnosis of psoriasis, but they cannot afford to pay for treatment for the moment. Every day, he undergoes a burning and itching sensation on his face that never sets.
“It has something to do with polluted air,” he speculated.
