• Government moots reviving stalled regional framework 
• Scientists point to northeast monsoon, Oct./March increase in air pollution
• Regional cooperation the only viable path to resolve problem

Sri Lanka will formally initiate discussions with neighbouring countries within this year to address the growing challenge of seasonal transboundary air pollution, Environment Minister Dammika Patabendi told The Sunday Morning.

He emphasised that regional cooperation was the only viable pathway to managing a problem that lay largely beyond the country’s borders.

The Minister’s comments come amid renewed public concern over recent dips in air quality across several parts of the island, which experts from environmental, technical, and health authorities have consistently attributed to recurring transboundary pollution rather than local emissions or the direct effects of Cyclone Ditwah.

Patabendi said assessments by the Central Environmental Authority (CEA) acknowledged that Sri Lanka’s air quality deterioration during this period was primarily driven by pollutants transported from the wider South Asian region. 

“Regarding the recent decline in air quality, the CEA’s assessment is consistent with the data we are seeing. This is fundamentally a transboundary pollution issue that recurs seasonally,” the Minister said.

He stressed that Sri Lanka could not address the issue in isolation and must instead pursue structured engagement with its neighbours. “To respond meaningfully, we must engage neighbouring countries in constructive dialogue. There is already an established regional framework for this purpose, but it has not been utilised to its full potential,” he said.

Reviving a regional framework

Patabendi pointed to the Malé Declaration on Control and Prevention of Air Pollution and its Likely Transboundary Effects for South Asia, adopted in 1998 under the South Asian Association for Regional Cooperation (SAARC), as the most appropriate foundation for renewed regional engagement.

“The Malé Declaration was created precisely to address issues like this. It recognises that air pollution does not respect national boundaries and that South Asian countries must work together to prevent and manage its transboundary impacts,” he said.

The declaration’s secretariat functions are handled by the South Asia Co-operative Environment Programme (SACEP), which is based in Colombo; an advantage, the Minister said, that Sri Lanka intended to leverage. 

“Despite the existence of this mechanism, its potential has not been fully realised due to inconsistent adherence by member states. Our immediate priority is to reinvigorate this framework and transform it into a genuinely functional platform for regional cooperation,” Patabendi said.

He underlined that progress would depend on consensus-building rather than coercion. “This is not an issue that can be resolved through compulsion. Cooperation is the only path forward. We want to use the Malé Declaration to foster trust, build consensus, and develop a shared regional approach to air pollution management,” he said.

According to the Minister, groundwork for this renewed engagement has already begun through diplomatic channels. “We have raised this matter in discussions with relevant countries at international forums, including meetings in Geneva and Fiji. The next step is to translate these bilateral and multilateral conversations into a unified regional stance,” he said.

Given the periodic nature of the problem and indications that it may intensify in the coming years, Patabendi said urgency was critical. “This issue is recurring and shows signs of worsening. I can assure the public that engagement is ongoing, and we are committed to formally initiating a structured regional dialogue within 2026 to seek a collaborative and sustainable solution,” he said.

Paris Agreement responsibilities

Addressing questions on Sri Lanka’s obligations under international climate agreements, the Minister said the country remained compliant with its commitments under the Paris Agreement but could not be held accountable for emissions generated outside its territory.

“Sri Lanka is meeting its responsibilities under the Paris Agreement. However, emissions that originate beyond our borders are the responsibility of the source countries, and they must be addressed within their own nationally determined contributions,” he said.

He added that recognising this distinction was essential for fair and effective global climate governance. “Our position is clear: while we will continue to reduce domestic emissions and strengthen environmental governance, the responsibility for controlling transboundary pollution lies with the countries where those emissions originate,” Patabendi said.

Scientific assessments confirm seasonal pattern

The Minister’s remarks align closely with scientific assessments by the CEA, which has repeatedly clarified that Sri Lanka’s air quality fluctuations follow a well-defined seasonal pattern rather than arising from isolated domestic events.

CEA Air Quality, Noise and Vibration Monitoring Unit Director Vernika Ranawaka Arachchi said that for several years, Sri Lanka had recorded a consistent rise in ambient particulate matter concentrations between October and March. “This period coincides with the northeast monsoon, when prevailing wind patterns facilitate the transport of polluted air masses from the Indian subcontinent towards Sri Lanka,” she said.

A major contributor, she explained, was large-scale agricultural residue burning, particularly paddy straw and husk, in countries such as India, Bangladesh, Pakistan, and Nepal following harvest seasons. “These activities release significant amounts of fine particulate matter into the atmosphere. Once emitted, these particles can remain suspended and be transported over long distances by regional wind systems,” Ranawaka Arachchi said.

She stressed that air pollutants did not recognise national borders. “Depending on wind direction, wind speed, atmospheric stability, and synoptic weather systems, these polluted air masses are carried into Sri Lanka. While the inflow is intermittent, the seasonal recurrence is now well established,” she said.

Cyclone Ditwah not the cause

Clarifying the role of Cyclone Ditwah, Ranawaka Arachchi said the cyclone did not generate air pollution and, in fact, temporarily improved air quality through wet deposition. “Heavy rainfall associated with the cyclone washed suspended particulate matter out of the atmosphere, resulting in a short-term improvement in air quality,” she said.

The deterioration observed after the cyclone, she explained, occurred once rainfall subsided and transboundary pollution resumed under favourable meteorological conditions. “Localised activities, such as debris burning, may contribute marginally in specific locations, but Sri Lanka’s domestic emissions are too low to account for the scale of pollution spikes we observe,” she said.

Evidence from monitoring and satellites

According to the CEA, Sri Lanka’s National Ambient Air Quality Standards are breached almost exclusively during this October-March window. “When we analyse data over the past five years, significant pollution episodes in Colombo, Jaffna, Puttalam, and other locations consistently align with this period,” Ranawaka Arachchi said.

She added that ground-based monitoring was supported by satellite-derived aerosol measurements and atmospheric transport modelling. “When these data sets are combined, the origin of polluted air masses becomes clear. The evidence strongly indicates that these events are transboundary in nature,” she said.

No domestic air pollution crisis: NBRO

The National Building Research Organisation (NBRO) has reached similar conclusions. 

NBRO Environmental Studies and Services Division Director H.D.S. Premasiri, said Sri Lanka was not facing a localised air pollution emergency. “The recent increase was a temporary phenomenon primarily driven by transboundary pollution entering the country depending on wind patterns. Similar short-term spikes have occurred in the past, even without major weather systems,” Premasiri said.

He noted that current Air Quality Index readings showed conditions ranging from good to moderate across the island. “There is no immediate risk from weather systems in the Bay of Bengal, and our indicators have returned to stable ‘Green’ levels,” he said.

Premasiri said NBRO data showed Sri Lanka enjoys good to moderate air quality for approximately nine months of the year, with temporary deterioration during the northeast monsoon. “Fine particulate matter such as PM2.5 does not remain trapped over Sri Lanka. As wind patterns change, these pollutants disperse, which is why air quality improves once meteorological conditions shift,” he said.

While discouraging localised burning, he stressed that its contribution at the national scale was negligible compared to transboundary sources.

Protecting public health

From a health perspective, authorities say seasonal air pollution episodes represent a manageable risk provided the public follows official advisories.

Ministry of Health Occupational Health Unit Head and Consultant Community Physician Dr. Inoka Suraweera said there was no evidence of a direct causal link between Cyclone Ditwah and recent Air Quality Index spikes. “These increases are consistent with transboundary air pollution commonly observed during this season,” she said.

The principal health concern, she explained, was elevated concentrations of PM2.5, which can penetrate deep into the lungs and enter the bloodstream. “Short-term exposure can cause allergic symptoms, headaches, eye irritation, breathing difficulties, and asthma exacerbations. Long-term exposure increases the risk of chronic respiratory disease, cardiovascular disease, lung cancer, and stroke,” Dr. Suraweera said.

She emphasised that children, pregnant women, the elderly, individuals with chronic illnesses, and outdoor workers were particularly vulnerable. “Air pollution is a major environmental risk factor, comparable to unhealthy diet or physical inactivity, in its contribution to non-communicable diseases,” she said.

The Ministry of Health advises the public to closely follow Air Quality Index-linked health advisories issued by the CEA, particularly during periods of poor air quality.

To minimise health impacts, the CEA is working with the Disaster Management Centre and the Department of Meteorology to strengthen air quality forecasting and early warning systems. “When poor air quality is predicted, we will issue public advisories recommending precautionary measures, especially for vulnerable groups,” Ranawaka Arachchi said.

The NBRO, according to Premasiri, issues daily air quality reports and has protocols in place to alert the media and public in the event of severe pollution episodes.

A regional challenge requiring regional resolve

Taken together, assessments by the Environment Ministry, CEA, NBRO, and Ministry of Health underscore that Sri Lanka’s air quality challenges are seasonal, externally driven, and deeply linked to regional emission patterns.

For Patabendi, this reality reinforces the need for diplomacy grounded in science. “Sri Lanka cannot solve this problem alone. What we can do, and what we will do, is lead by example, comply with our international commitments, protect our citizens, and work tirelessly to build a regional consensus,” the Minister said.

“With the Malé Declaration as our foundation and structured dialogue beginning within this year, we are committed to ensuring that transboundary air pollution is addressed as a shared South Asian responsibility,” he stressed.