Ahead of Diwali, Delhi’s AQI has hit a massive high of 600 and apparently it is not coming down soon enough. As the air quality begins to deteriorate during the winter in Delhi and the NCR, many people are likely to suffer from coughing, shortness of breath, sore eyes or even worse asthma. However, some issues caused by air pollution can be quite subtle.
The lungs are the first major organ to come into contact with polluted air; however, research shows that long term exposure to fine particulate matter can cause cardiovascular issues, altered metabolism, kidney issues and even pregnancy complications. Scientists are also looking into how pollution can affect the brain, skin and eyes.
One of the main issues causing concern is PM2.5 particles, which are 2.5 micrometers or smaller. Due to their size, they can travel deep in the lungs, causing inflammation and oxidative stress.
This means that air pollution is a significant public health issue in Delhi.
Air pollution and its effect on the cardiovascular system is a well researched topics. Fine particles can cause inflammation and oxidative stress in the lungs. This can lead to issues with the endothelium, a layer of cells which lines the blood vessels and helps them function properly when healthy.
Research has shown that exposure to air pollution can cause altered blood pressure, vascular dysfunction and issues with the clotting cascade. This could ultimately lead to an increased risk of heart attacks, strokes and other cardiovascular related issues.
A study found that air pollution is an important risk factor for cardiovascular diseases. People with underlying issues such as hypertension, diabetes or existing heart issues may be at greater risk however, long term exposure can also cause cardiovascular risks in otherwise healthy individuals.1
Research has emerged on the effects of air pollution and its impact on the brain. Research is being conducted on how air pollutants can induce inflammatory and oxidative stress responses along with pathways connecting the respiratory system and brain. Some particles may affect the nervous system through the olfactory pathway due to their small size.
This has caused concerns of how long term exposure can result in changes to cognition. Many studies have shown associations between air pollution and cognitive decline. Scientists are investigating how air pollution can cause neurological and psychiatric issues.
The risks of air pollution to neurological and psychiatric health are real. The potential mechanisms which can cause neuro-inflammation and oxidative stress should be investigated. This does, however, not mean air pollution will cause a particular neurological or mental health issue.2
The kidneys are constantly working to remove waste from the blood and keep the fluids and electrolytes in balance. This means they rely heavily on good blood flow and could be at risk if there is an issue with circulation and inflammation.
A study published in 2026 looked at 12,271 adults from Delhi and Chennai. They found that those exposed to higher levels of PM2.5 over the long term had lower eGFR (estimated glomerular filtration rate) which indicates how effectively the kidneys filter their blood.3
This is important as kidney issues can be gradual and one may not notice any clear symptoms in the early stages.
While this doesn’t show that the issue was specifically caused by air pollution, it adds to the evidence that environmental exposure may be a factor in kidney health. Those with diabetes, hypertension or chronic kidney disease may be more at risk.
Air pollution can also have an impact on body’s ability to process glucose. A study published in 2023 looked at the relationship between PM2.5 exposure, glucose levels and type 2 diabetes in adults from Delhi and Chennai.4
They found associations between increased particulate matter exposure and altered fasting blood glucose levels and HbA1c, a measure of your average blood sugar levels over around 3 months. They also found associations between increased long term exposure and incidence of type 2 diabetes.4
Scientists mentioned that this could be due to inflammation and oxidative stress affecting insulin sensitivity. If your body isn’t responding to insulin as well it can struggle to control blood glucose.
Pregnancy is another time to be mindful of exposure to environmental pollutants.
The placenta provides oxygen and nutrients to the baby while they are growing. Researchers are looking into how inflammation, oxidative stress and placental issues caused by air pollution could affect this.
Studies have found associations between particulate matter, and other pollutants and negative pregnancy outcomes including preterm births and low birthweight babies. These pollutants affect placental health and have negative birth outcomes.5
The eyes and skin are directly exposed to what is going on around you meaning they can be affected by airborne irritants.
Those exposed to polluted air may suffer from dry eyes, redness, itchiness, watering and a burning sensation. Particulate matter can cause irritation to the surface of the eye and can worsen existing dry eye or allergic eye issues.7
The skin can also be affected by airborne particles and chemicals. Some studies have shown that pollution may cause oxidative stress, damage to the skin barrier and inflammatory skin issues.6
India has introduced various initiatives to improve its air quality.
The National Clean Air Programme was launched in 2019. It covers 130 cities and aims to reduce particulate matter by implementing various methods such as dust control, waste management, air quality monitoring and targeting emissions.
Delhi-NCR has the Graded Response Action Plan (GRAP). This means stricter measures are implemented as air quality worsens. Under the updated schedule, there are 4 levels:
Stage I – Poor (201-300)
Stage II – Very Poor (301-400)
Stage III – Severe (401-450)
Stage IV – Severe+ (>450)
Depending on the stage, there may be restrictions on construction, vehicles and some industries. The schedule was updated by the Commission for Air Quality Management (CAQM) in September 2026.
The National Programme on Climate Change and Human Health (NPCCHH) managed by the Ministry of Health and Family Welfare also works to improve preparedness for health issues caused by climate change.
Generally, long-term exposure has an effect on health. However, some people are more at risk of complications, these include:
Children – This is due to their lungs and other organs still developing. They may also breathe in more air in proportion to their body weight.
Older people – Due to age related changes in their body or pre-existing cardiovascular and respiratory issues.
Pregnant women – Being exposed to Air Pollution can cause negative outcomes in pregnancy.
Pre-existing conditions – Those suffering from asthma, Diabetes, Hypertension, Heart disease and Kidney disease.
Outdoor workers – Those working in traffic such as traffic staff, builders, street vendors and delivery workers may be more prone to long term exposure.
While government policies and pollution controls are needed to address Air Pollution, there are steps you can take to reduce your exposure.
People should try to work indoors, purchase air filters or avoid travel during periods of high Air Pollution.
If you cannot avoid being outside, wearing a N95 mask which fits well will help reduce the amount of fine particulate matter breathed in.
Try to avoid intense exercise outdoors while pollution levels are high.
Keep windows shut during times of high outside pollution and use HEPA air purifiers (correct size) indoors if possible.
During times of severe pollution, children, older people and those with pre-existing health conditions should take extra precautions. If experiencing ongoing breathing problems, chest pain, unexplained tiredness or any other worrying symptoms, seek medical advice.
Stay hydrated and eat a balanced diet but do not rely on this to help reduce your exposure to polluted air.
The pollution crisis in Delhi cannot just be seen from coughing, shortness of breath and visiting the hospital with respiratory issues. Research has shown that air pollution can cause cardiovascular, neurological, kidney, metabolic and pregnancy issues meaning it needs to be considered as a public health issue.
While there are steps you can take to reduce your exposure, long term actions need to be made to reduce emissions from vehicles, dust from construction, pollution from industries and better waste management. Having accurate air quality monitoring, honest reporting and consistent clean air policies are also key.
Clean air shouldn’t just be a seasonal luxury. We need to consider air pollution as an issue throughout the year to protect public health.
References:
Khoshakhlagh et al. (2024), Globalization and Health — Cardiovascular disease burden attributed to air pollution
Sethi et al. (2024), Archives of Medical Research — Impact of air pollution on neurological and psychiatric health
Mandal et al. (2026), Kidney International Reports — PM2.5 exposure and kidney function in urban Indian adults
(2023), BMJ Open Diabetes Research & Care — PM2.5 exposure, glycemic markers and type 2 diabetes in Indian cities
Fussell et al. (2024), BJOG — Air pollution and adverse birth outcomes
Singh et al. (2026), American Journal of Clinical Dermatology — Air pollution and skin diseases
Iqbal et al. (2025), The Ocular Surface — Particulate matter and ocular surface disease
