- Transboundary pollution, microplastics may have significant health impact
Air pollution is increasingly becoming a national health issue, with the 2025 World Health Organization (WHO) Health and Environment Scorecard for Sri Lanka stating that air pollution is a primary driver of cardiovascular mortality.
“If we are otherwise healthy, when we breathe bad air, we don’t feel it immediately unless the pollution is severe,” said Consultant Pulmonologist Dr. Neranjan Dissanayake. “But unfortunately, these health effects are silently killing us without us even knowing.”
This ‘silent killer’ is exacerbated by a lack of clean energy at home; the same report notes that 65% of the population still lacks clean fuels and technology for cooking, creating a dual burden of toxic exposure.
The data highlights a stark gap in safety: Sri Lanka’s annual mean PM2.5 concentration stands at 24 µg per cubic metre, nearly five times higher than the WHO’s safe guideline of 5 µg per cubic metre.
Furthermore, while legal standards for air quality exist, the WHO explicitly flags them as non-compliant with global safety guidelines, leaving the public vulnerable to events like the hazardous smog spikes seen this January.
While commuters in Colombo squint through the dense grey haze and check their phone apps for air-quality updates, the true scale of the crisis is unfolding not in the sky, but deep within the human body.
Anatomy of the threat
In a comprehensive examination of Sri Lanka’s air quality crisis, Dr. Dissanayake laid bare a devastation that goes far beyond a seasonal cough, describing a “silent killer” that dismantles human health from the inside out.
To understand the danger, one must look past the colour-coded warnings of the Air Quality Index (AQI) and focus on the microscopic reality. Dr. Dissanayake argued that the true enemy was Particulate Matter (PM), breaking down the threat by size to reveal exactly how it invaded the body.
“The largest particulate matter, PM10, is about 10 microns in diameter or roughly one-tenth the width of a human hair,” he explained. Because of their relative size, these particles are often trapped in the upper respiratory tract. “These particles usually affect the nasopharyngeal area, or the upper airways.”
As the particles get smaller, they penetrate deeper. “The second group, PM2.5, affects the bronchi – the airways crucial for breathing. This is the primary trigger for conditions like asthma.”
However, the threat does not stop at the lungs. Dr. Dissanayake identified PM0.1, the smallest category, as a systemic poison that bypassed the body’s natural defences entirely. “The most critical aspect is PM0.1. Because these particles are too small to be filtered out by the body’s natural mechanisms, they travel all the way to the alveoli, the deepest part of the lung,” he warned.
At this microscopic level, the lung’s biological defence mechanisms fail. The barrier between the alveoli and the bloodstream is incredibly thin, designed to facilitate oxygen exchange. This permeability allows ultrafine pollutants to bypass the lung completely.
Once in the bloodstream, air pollution ceases to be solely a respiratory issue and becomes a cardiovascular and metabolic one. Exposure to these particles increases the risk of strokes and cardiac diseases. “Research shows it affects blood sugar control and can lead to diabetes with long-term exposure,” Dr. Dissanayake added.
Threat to future generations
Perhaps the most alarming revelation from Dr. Dissanayake is the impact on pregnancy and the unborn. The medical evidence suggests that the placenta, usually a protective barrier for the foetus, is no match for these ultrafine pollutants.
“If a pregnant mother is exposed, these particles can penetrate the placenta,” he said. “This has been shown to reduce foetal growth rates, cause congenital abnormalities, and lead to premature births.”
The damage may not even stop with the child born today. Dr. Dissanayake introduced the terrifying concept of intergenerational damage, where pollutants affect the developing reproductive systems of the foetus.
“In a growing foetus, the germ cells within the gonads are developing,” he explained. “Certain air pollutants can actually alter the genetic structure and expression of these cells. This means the damage doesn’t just affect the current generation; it can impact multiple future generations.”
The implications are profound. A mother breathing polluted air today could effectively be transmitting health risks to her grandchildren. “We really don’t know what the genetic consequences will be,” he said.
The current context
While Dr. Dissanayake outlined the physiological stakes, the environmental reality in Colombo confirms the urgency of his warnings. For weeks, the Air Quality Index in the Western Province has hovered at alarming levels. While the public looks to the sky, the authorities are looking at the data, and the numbers are stubborn.
Central Environmental Authority (CEA) Director of Air Quality, Noise, and Vibration Monitoring Vernika Ranawaka Arachchi provided a sobering assessment of the islandwide situation. While recent rains offer hope, the pollution has been persistent.
“Throughout this week, pollution levels have remained elevated,” Ranawaka Arachchi said. “We are observing an islandwide average between 100 and 120, occasionally spiking to 150.”
She noted that while there were predictions that the situation may ease soon, the persistence of the haze was undeniable. “Predictions suggest it will be easing over the coming days, but we cannot say it is entirely over. The pollution levels will decline to some extent with prevailing conditions and we will continue to monitor the situation.”
Disaster Management Centre (DMC) Director of Preparedness and Planning Chathura Liyanaarachchi confirmed that his agency had been tracking these spikes closely through a network of monitoring stations established by the National Building Research Organisation (NBRO), the US Embassy, and the CEA.
“We have observed this drop in air quality on our dashboard,” Liyanaarachchi stated. “This is largely due to the pollution coming from India and the region.”
The meteorological trap
Both the CEA and the DMC agree on the primary culprit being the northeast monsoon. Unlike other weather patterns that might disperse pollutants, this season turns Sri Lanka into a catchment area for regional smog.
“During the northeast monsoon, air flowing from India transfers regional pollution to Sri Lanka,” Liyanaarachchi explained. “Without strong winds to disperse it, the smog stagnates. This is a pattern we have observed in previous years as well.”
Ranawaka Arachchi added a new dimension to this meteorological trap by suggesting the influence of climate change. She noted that the patterns of pollution transport were shifting, making the situation harder to predict than in previous years. “We believe climate change is influencing air quality trends, altering wind patterns, turbulence, and speed, all of which affect how pollution is transported here,” she noted.
When asked if the Government could intervene to minimise this specific pollution source, Liyanaarachchi was blunt about the limitations of human intervention against transboundary weather patterns. “For transboundary pollution, there is little we can do,” he admitted. “We have to wait for the wind to carry these pollutants away.”
This reality creates a dangerous status quo where the country is essentially waiting for the weather to change. In the interim, the burden of safety falls entirely on adaptation. Liyanaarachchi noted that during these peak periods, those with the means often took drastic measures, highlighting a stark inequality in who got to breathe clean air.
“Some embassies have separate rooms with oxygenated air,” he noted. “Some people even move out of the Western Province. That might be a good option if one can afford to relocate for a few days.”
The data gap and historical blind spots
A critical friction point remains between what medical professionals see in global studies and what local authorities can prove with local data.
Recently, reports have indicated a spike in lung-related illnesses in children, particularly in January. While Dr. Dissanayake confirmed that air quality had been shown to be directly proportional to hospital admissions due to exacerbations of certain diseases, he also noted other factors such as the influenza season which might have contributed.
Ranawaka Arachchi was even more cautious and revealed a critical gap in Sri Lanka’s scientific infrastructure: the lack of local research to definitively link specific health spikes to air quality. “We suspect air quality plays a role, but we lack the research findings to directly correlate pollution with these specific health spikes,” she admitted. “The root causes, whether weather, humidity, or influenza, have not been clearly isolated.”
She explained that distinguishing between the effects of humidity, rain, viral influenza, and pollution was currently impossible without more rigorous study. “We cannot say it is influenced by air pollution alone, though it certainly plays a role.”
This lack of data extends to historical trends as well. When asked if air quality was getting worse year-on-year, Ranawaka Arachchi pointed out that the CEA simply had not had the eyes on the ground in previous decades to make a fair comparison. “We can see an increasing trend year-on-year, but comparing it to the past is difficult because we had fewer monitoring stations back then. That historical data gap makes it difficult to define the long-term trend with certainty.”
However, she noted that modern data from 2020 to 2022 showed a consistent and worrying pattern. “When we plot the trend line, we see the same worrying pattern emerging repeatedly.”
The mask dilemma
In the face of this dual threat of transboundary smog outside and chemical irritants inside, the question of public safety measures has become a point of contention, specifically regarding masking.
DMC Director of Preparedness and Planning Liyanaarachchi leant towards caution and acknowledged the protective value of masks given the current PM2.5 levels. “If PM2.5 levels are high, fine particles can enter the lungs and bloodstream. In that case, it is better to wear a mask,” he advised.
However, Ranawaka Arachchi clarified that this was an advisory rather than a mandate. The Government is stopping short of making masks compulsory and is leaving the decision to individual discretion. “We advise those who feel uncomfortable, or those suffering from asthma and respiratory diseases, to wear N95 masks,” she said.
When asked if a mandate was on the horizon, she said: “A mandate would require a decision from the Ministry of Health. Currently, it depends on individual tolerance. We haven’t yet observed the type of severe public health deterioration that would necessitate a compulsory order.”
No option to opt out
The authorities act as monitors, publishing data and waiting for the winds to shift. The medical community treats the fallout but warns of long-term genetic consequences. This leaves the burden of protection squarely on the individual.
Dr. Dissanayake framed the battle against air pollution as a fight for survival that did not allow for opting out. Unlike food or water, where one can choose safer options, air is non-negotiable. “If you have diabetes, you can avoid sugar,” he reasoned. “But you cannot stop breathing. Even in a maximally polluted environment, you must breathe to survive.”
For now, the advice is a mix of drastic adaptation and careful hygiene. The experts suggest checking the DMC and NBRO dashboards, wearing a mask if you feel uncomfortable or have respiratory issues, cleaning your home of dust and smoke sources, and understanding that the grey sky is not just a weather event but a public health warning written in the air.
Box
The danger within our walls: Indoor air pollution
With the external environment largely dictated by transboundary winds and a lack of regulatory mandates, Consultant Pulmonologist Dr. Neranjan Dissanayake highlighted that indoor air pollution was the one battleground where Sri Lankans still had agency.
“We may not be able to change the external environment immediately, but we can certainly control our internal environment,” he asserted. “Unfortunately, many of our own homes are heavily polluted.”
He identified common household items as significant offenders. “We burn mosquito coils and incense sticks, which release huge amounts of particulate matter,” he noted. “We also use chemical cleaners that are known to increase the risk of asthma.”
In suburban and rural areas, the use of biomass fuel remains a primary health hazard. “The use of kerosene and firewood for heating and cooking releases high levels of particulate matter,” he explained. He painted a vivid picture of the cultural transmission of this risk. “Children left with grandmothers who cook with firewood are exposed to this smoke. This increases their risk of asthma, pneumonia, and lower respiratory tract infections.”
Compounding the chemical pollution is the biological pollution found in many Sri Lankan bedrooms. Dr. Dissanayake highlighted how clutter led to dust accumulation, cockroach infestations, and the proliferation of dust mites which were a leading cause of allergies in the country.
“Storing too many clothes in our rooms harms ventilation and traps allergens like dust mites,” he said. “A patient with allergic rhinitis or asthma might wake up sneezing or wheezing simply because they slept in a cluttered, dusty room.”
The window of vulnerability
The urgency of addressing both indoor and outdoor air quality is most acute for adolescents and young adults whose physiological development creates a critical window of vulnerability. Dr. Dissanayake explained that human lungs did not stop growing at birth but continued to develop until early adulthood. “The human lung continues to grow until about age 24, at which point it reaches its maximum peak function,” he stated.
However, if a child is exposed to pollutants starting from the womb and continuing through childhood exposure to firewood smoke or allergens, their lung development is stunted. “A child exposed in the womb is born with lower lung volume,” he illustrated. “If they are repeatedly exposed to firewood smoke or allergens, by their teenage years, their lung function will have significantly deteriorated. They will never reach the peak potential they would have had.”
Since lung function naturally declines after the age of 25 for everyone, these children begin their adult lives with a deficit. “They start adulthood with lower lung function and may become ill at a much earlier stage in life,” he warned.
Dr. Dissanayake also addressed voluntary behaviours that exacerbate lung damage, specifically targeting the rise of vaping among youth. He debunked the myth that vaping was a safe alternative to smoking.
“People think vaping is harmless, but it contains nicotine and involves inhaling substances directly into the lung,” he said. He references the 2019 outbreak of E-cigarette or Vaping Use-Associated Lung Injury (EVALI) in the US. “In 2019, the EVALI outbreak killed over 2,300 people in the US alone. Vaping is a significant source of pollution.”
He emphasised that unlike muscles which can be built up through exercise, the lung was a “defined structure”. “You can train your muscles or your cardiovascular system, but lung volume is structural and defined. No amount of exercise can increase it,” he explained. “The lung is a delicate organ. Unlike a kidney, which can be transplanted, lung transplants are not currently available in Sri Lanka.”