Maharashtra, India — When Babytai Suryavanshi first noticed some scaly patches on her right forearm, she ignored them for three months, thinking it was an infection that would heal in itself.
While working in a sorghum field last year, she noticed that the patch was more raised, reddish and burning.
You might like it
What Suryavanshi, 76, didn’t know about, and what researchers are now revealing is that air pollution could play a role in triggering and exacerbating the disease.
Approximately 99% of the world’s population is exposed to air that does not meet the World Health Organization’s air quality guidelines. In 2021, 42.98 million people were diagnosed with psoriasis. However, studies suggest that many people may not be diagnosed as easily mistaken for other conditions and finding dark skin tones is more difficult. Some estimates suggest that 125 million people are affected worldwide.
For Suryavanshi, the link between her skin condition and contamination became clear after the doctor asked her to pay attention to her environment. For over 30 years, she worked at a sugarcane planting nursery near her home in Jambari village in western India. She quit last year as sugarcane residue and constant smoke from trays of plastic seedlings had repeatedly caused flare-ups, she said. Now she works on a farm, but it also poses a risk as nearby factories often expose her to polluted air.
New Link
Air pollution is a term that includes a variety of chemicals and particles that humans expel into the air through industrial activities, from driving a factory to driving a car. From wildfire smoke to smog, it covers everything. It contains particulate matter of various sizes, including PM2.5 (PM2.5) smaller 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 state in which the immune system attacks the body’s tissues, that is, skin cells. People usually have flare-ups in a condition that is being treated with creams, phototherapy, or medications that calm the immune response. This condition tends to run in families, which has a genetic component that makes people more vulnerable.
However, genes are not the only factor. The link between psoriasis and contamination has been found in several studies around the world.
For example, one analysis included approximately 285,000 people from Biobank in the UK, a repository of health data and biological samples from adults in the UK who had been followed for 15 years. It has been shown that long-term exposure to contamination can accelerate biological aging. They measured this aging using a phenogen algorithm. This is a tool known as the “aging clock” that estimates the biological age of the body, rather than just years. This estimate indicates whether the body ages faster or slower than the average healthy baseline, indicating whether it is predictable for the risk of death from the cause or incidence of age-related diseases such as cancer.
You might like it
This increase in aging metric is associated with an increased risk of psoriasis, with a one-year increase in biological age being linked to a 5% higher risk of condition.
Another study from Verona, Italy found a temporary link between high pollination days and flare-up of psoriasis. This study tracked the city’s contamination levels, down to patients visiting the clinic to receive treatment for post-dryness, and averaged contamination levels over the past 60 days. The results showed that high exposure to air pollution in that time frame defined as passing a certain threshold of PM2.5 and PM10 increased the likelihood of visits for these flare-ups.
Additionally, a 2024 study in over 3,600 Americans examined the relationship between psoriasis and urinary polyaromatic hydrocarbon (PAH) metabolites. It is a component of air pollution that is formed during the combustion of coal and oil, waste, and other carbon-based materials. People with high levels of PAH metabolites – those who showed higher recent exposure were 83% more likely to suffer from psoriasis. Another US-based study published in 2023 had linked clinical visits for psoriasis to contamination caused by wildfire smoke.
Even short spikes of contamination can increase the risk of psoriasis-related medical visits. A five-year Chinese assessment examined the levels of several contaminants, including nitrogen dioxide and carbon monoxide, and found a linear relationship between elevated contaminant levels and psoriasis-related visits to physicians. The extent of the increase in delay between exposure and outpatient visits depends on the particular contaminant being measured, but there was usually a lag of several days to one week.
The cause is revealed
These studies point to some link between contamination and psoriasis, but scientists are now investigating precisely and in depth how contaminated air causes or worsens the condition. And although the answer is complicated, it is beginning to emerge.
Some studies suggest that small particles during contamination can directly damage the outer barrier of the body, causing disruption to the skin both physically and chemically.
For example, Shin, who wrote a paper on genetic and environmental risk factors for psoriasis, has shown that microparticles cause changes in skin protein and fat. These changes can destroy enzymes in the body’s antioxidant defense system that cleanse tissue damage caused by free radicals such as reactive oxygen and nitrogen species. Air pollution can also increase the production of reactive nitrogen species in human tissues, particularly skin, Singh added.
Dr. Paolo Gisondi, an associate professor in the Department of Dermatology at the University of Verona, who co-authored the Italian study, said that while the exact biological mechanisms are not fully understood, “it can be speculated that air pollutants can cause skin inflammation by activating immune cells and promoting the release of inflammatory molecules.” This abnormal immune activation can lead to psoriasis.
Singh also noted that in laboratory dishes with stem cells developed in skin cells, the smallest component of air pollution, less than 0.1 micrometers, each could increase the activity of genes associated with inflammation and psoriasis. In lab dishes, ultrafine particles can also destroy the normal development of keratinocytes, the main cells of the outer coat layer.
A paper published this year examined UK biobank data and identified specific genes that could be involved in mechanisms: Zmizi. This gene usually helps regulate the immune system, with inflammation and air pollution being linked to changes in its activity. The ZMIZ1 acts as a dial to fine-tune inflammation levels. However, air pollution can cause inflammation and increase the likelihood of autoimmune diseases like psoriasis, as it traps the dial in a “higher” position, research has found.
What can you do?
At individual levels, people can stay indoors on high pollination days and use air purifiers to reduce contaminating exposure, Singh said. And if you have to go outside, you can try to limit the number of these small particles that penetrate the skin and hair follicles by covering exposed parts of your body with protective clothing. Products that remove particle buildup from the skin can also be periodically purified or exfoliated, Singh added.
However, Singh emphasized the need for broader regulatory actions. In addition to passing regulations to reduce air pollution, the government needs to develop stronger early warning systems for high pollination days.
For residents like Suryavanshi, it is difficult to take steps to avoid triggering psoriasis.
Their village has more than 100 sugarcane nursery schools, both large and small, each causing contamination, she said. Like others in her neighborhood, she also heats the water to bathe daily on a wood stove, which exposes her to additional smoke contamination.
Her husband, 78-year-old Mahadev Suryavansi, was also diagnosed with psoriasis last month, but now she can’t afford to pay for the treatment. Every day he endures the fiery itchy sensations on his face that never sinks.
“It has something to do with polluted air,” he speculated.
Source link
