From Kannur to Ny-Alesund, researcher tracks pollutants into the Arctic

Manoj Panayamthatta Rayaroth, a senior scientist at the GITAM Institute of Oceanography, has spent the past six months journeying from the tropical coasts of Kannur in Kerala to the remote fjords of Ny‑Ålesund on Svalbard, tracing the pathways that industrial chemicals take from their point of origin to the fragile Arctic environment. The expedition, part of the Indian Arctic Programme 2026‑27, aims to map the transformation of persistent organic pollutants (POPs) as they travel through oceanic currents, become incorporated into sea ice, and eventually melt back into the marine system. Rayaroth’s work builds on a growing body of research that suggests pollutants once thought confined to temperate zones are now surfacing in the high latitudes at unprecedented rates.The Indian Arctic Expedition, a collaborative venture involving the Ministry of Earth Sciences, the National Centre for Polar and Ocean Research and several university partners, set sail from Kochi in early November 2025..

The fleet of research vessels, equipped with state‑of‑the‑art sampling equipment, made a series of stops along the Indian Ocean, the Arabian Sea and the Bay of Bengal before entering the Atlantic. Along the way, water samples were collected at predetermined transects to establish a baseline of contaminant concentrations in waters that feed the global thermohaline circulation. “We wanted to understand not just the end‑point in the Arctic, but the entire journey of these chemicals,” Rayaroth explained during a briefing in Oslo last week.In the fjords surrounding Ny‑Ålesund, the team focused on two primary sources of water: meltwater streaming from the retreating Vestfonna glacier and the saline fjord waters that receive runoff from the surrounding tundra..

Samples were taken at varying depths using Niskin bottles, and the water was filtered on board to isolate dissolved organic matter. The filtered material was then subjected to high‑resolution mass spectrometry, allowing the identification of trace levels of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and newer classes of flame retardants that have entered the market over the past decade.Preliminary results reveal a striking pattern: concentrations of certain POPs, particularly legacy PCBs, are higher in the meltwater than in the surrounding seawater. This suggests that as glaciers erode, they release previously trapped pollutants that have been stored in the ice for decades, a phenomenon first noted in Antarctic studies but now evident in the Arctic..

“Glaciers act like time capsules,” said Dr. Elena Mikkelsen, a glaciologist from the University of Oslo who is part of the same research team. “When they melt, they release a cocktail of chemicals that have been locked away, re‑introducing them to ecosystems that have been relatively pristine until now.”The implications for marine life are significant..

In laboratory analyses conducted later in the expedition, researchers cultured phytoplankton to water samples containing the identified pollutants. The organisms displayed reduced photosynthetic efficiency and altered lipid profiles, indicating that even low concentrations can disrupt foundational components of the Arctic food web. Higher trophic levels, such as zooplankton, fish and seabirds, could accumulate these substances through biomagnification, posing risks to species already stressed by warming temperatures and sea‑ice loss.Rayaroth’s team also examined the role of sea‑ice formation in concentrating pollutants..

As seawater freezes, certain chemicals are excluded from the ice lattice and become enriched in the brine channels that form within the ice. When the ice later thaws, these concentrated pockets are released in a short burst, potentially creating hotspots of contamination in otherwise low‑pollution waters. Measurements taken from freshly formed ice cores near the Brøgger Peninsula showed PCB levels up to three times higher than in the ambient seawater, corroborating earlier findings from Canadian Arctic research stations.To contextualise these findings, the expedition compared current data with historical records from the 1990s, when the first systematic Arctic contaminant monitoring programmes began..

Over the past three decades, the total burden of POPs in the Arctic has shown a modest decline in some regions, reflecting global regulatory efforts such as the Stockholm Convention. However, Rayaroth’s data indicate a nuanced picture: while legacy pollutants are decreasing, newer compounds—particularly certain brominated flame retardants—are on the rise. “Regulation often lags behind innovation,” he noted..

“Chemicals introduced as safer alternatives can end up being just as persistent and bio‑accumulative.”The research also highlights the interconnectedness of climate change and pollutant dynamics. Accelerated glacier melt, driven by rising atmospheric temperatures, not only contributes to sea‑level rise but also accelerates the release of trapped contaminants. Moreover, changes in ocean circulation patterns may transport these substances farther and faster than previously modeled..

The team employed satellite‑derived sea‑surface temperature data alongside ocean‑current simulations to predict future dispersal pathways, concluding that the western Arctic could see a 15‑20 percent increase in POP concentrations by 2050 if current trends continue.International stakeholders have taken note. The Arctic Council’s Working Group on Monitoring and Assessment is set to review the Indian expedition’s findings at its next session in Reykjavik. Discussions are already underway about integrating the new data into the Arctic Monitoring and Assessment Programme (AMAP) database, which informs policy decisions across the eight Arctic nations..

“Science from non‑Arctic countries like India enriches our collective understanding and underscores the global nature of these challenges,” said Maria Kovacs, AMAP’s scientific coordinator.As the research vessel Arka set sail from Svalbard toward the North Atlantic in early January, the team began the long journey back to India, carrying with them a trove of samples that will be analysed further in laboratories in Pune and Tromsø. The next phase will involve detailed toxicological assessments and the development of predictive models that can inform both regional mitigation strategies and global chemical policy. For Rayaroth, the work is as much about data as it is about advocacy..

“When the ice melts, it tells a story,” he said. “Our job is to listen, interpret and act before that story becomes a warning we can no longer ignore.”.