Microplastics are plaguing the Arctic
In recent years, the pollution of our oceans with plastic waste is a problem of growing environmental concern. Every year, around 8 to 12 million tons of plastic enter the oceans as marine litter due to mishandling of litter in coastal areas. Now, in a study, scientists from Goa’s National Center for Polar and Ocean Research (NCPOR) scientific institution have found large amounts of plastic waste on the west coast of Spitsbergen, part of Norway, in the Arctic Ocean. SHASHWAT GUPTA RAY finds out the essence of the study and future impacts on Arctic ecology due to plastic pollution
The phenomenon of climate change now presents us with a new challenge. While the melting of glaciers caused by global warming is leading to sea level rise and extreme weather events, it has also increased human activities in the polar region such as commercial shipping, fishing activity and the influx of tourists among others. All of this leads to a threat of microplastic pollution in the sea in the pristine polar regions.
Now, a study by scientists from the National Center for Polar and Ocean Research (NCPOR) Goa has now found the presence of microplastics in the Arctic caused by increased human activity. This poses a major threat to marine life and humans as it enters the human food chain through marine organisms such as fish.
The results of the study were published in the journal Marine Pollution Bulletin.
Microplastic pollution has emerged as one of the most serious global problems as it poses a significant ecological risk to marine ecosystems.
“The Arctic region, considered pristine, is also a sink for pollutants caused by human activities and transported by long-distance atmospheric transport and ocean processes despite its remote and isolated location,” Shabnam Choudhary, National Post Doctorate Fellow at NCPOR and leader, said the author of the study.
Human activities in the Arctic are often mentioned as recipients of climate change impacts, although they are of moderate magnitude. As more melting ice-free areas and sea lanes open up, human impact could increase significantly in the near future.
The Krossfjord and Kongsfjord system (78°40ʼ and 77°30ʼN and 11°3ʼ and 13°6ʼE) on the west coast of Svalbard, Arctic, is heavily influenced by the West Spitsbergen Current, which carries a significant amount of sediment, water and pollutants into the Arctic transported fiord.
The sediments act as a retention site or sink for the microplastics and this fjord system is ideal for studying the microplastics.
“Surface sediments of the Krossfjord-Kongsfjord system were studied to assess the source, abundance and distribution of microplastics. The abundance (721 pieces/kg and 783 pieces/kg in Krossfjord and Kongsfjord, respectively) of microplastics was high in the fjord, indicating the strong influence of anthropogenic activity,” said Choudhary.
Fibers were the most common type of microplastic particles in the Arctic, as a large number of ports are concentrated in the Arctic and sub-Arctic region around the Bering Sea and Norwegian Sea.
Possible sources of these fibers include sewage, packaging materials, ropes, nets and fishing line, as anthropogenic activities such as fishing and tourism have increased in recent years due to declining sea ice.
“Marine organisms ingest these small plastic particles because they resemble the food source and can be transferred to different trophic levels of the food chain that affect humans,” the scientist said.
The study was co-authored by Syed Mohammad Saalim of NCPOR and KannaiyanNeelavanan of IIT Kanpur.
“Climate change is bringing multiple layers of challenges to the Arctic. On the one hand, we see increased human activities that create potential for economic development – particularly in mining, oil and gas, shipping, fisheries and tourism. On the other hand, these economic benefits pose a risk to the environment, local people and the traditional livelihoods of indigenous people,” Choudhary said.
The number of tourist ships calling at Longyearbyen harbor and the number of passengers increase as the sea ice extent decreases, leading to an increase in the amount of microplastics. Tourism and pleasure craft passengers have steadily increased over a period of nearly two decades. The latter reached 87,000 passengers per year in 2017.
“The post-2011 period of high litter density coincides with an increase in maritime activity near Svalbard, both from tourism and fishing vessels, which may contribute to the pollution observed in the Arctic. The mean annual waste density was significantly different in the Arctic Ocean. An initially strong increase in 2011 was followed by increased values of over 6,000 units km-2 from 2014. The composition of observed debris varied significantly over the years in the Arctic Ocean,” she said.
Plastic bags, packing materials and fishing gear were the most common form of plastic. This material made up nearly 41% of all debris, with a significant increase after 2014. The second most common type was broken glass (21%). Other types of material such as scrap metal, synthetic cord, wood, fragments of pottery and a likely discarded fish carcass accounted for less than 10%.
The debris recovered was mostly smaller, raising concerns about further fragmentation and pollution from microplastics, particularly as the amount of small plastic has continued to increase after 2014. Long-distance transport by the West Spitsbergen Current along with sea ice, glacial melt and atmospheric wind transport are possible sources of microplastics in the Arctic Ocean.
In addition, local sources such as sewage, packaging material and fishing gear have also contributed to a greater extent. Marine organisms ingest small plastic particles because they resemble the food source and can be transferred to different trophic levels of the food chain. The level of the biological effect is determined by the amount and type of microplastics ingested. Interestingly, interactions between microplastics and organisms are more common in the Arctic than in subtropical gyres, as the co-occurrence of plastic and organisms is high in this highly productive water.
The effect of entanglement in sessile organisms is uncertain, but can result in injury or reduced water exchange and respiration rates due to covering of the affected body surface, obstruction of filter feed, and adverse reproductive effects. Addressing the problem requires stricter waste management systems to prevent accidental spills of litter into the ocean, particularly in densely populated coastal areas where most litter originates and travels long distances.
“Regulations in the maritime industry need to be tightened to prevent litter dumping, but cost-effective systems are also needed to properly dispose of fishing gear and ship-generated waste. Beyond these actions, societal change is imperative to better balance the need met by plastics and the convenience they provide,” she said.
According to the director of the National Institute of Oceanography (NIO), Dr. Sunil Kumar Singh, who found large amounts of microplastics off the coast of Goa, said: “A lot of microplastics come from long-distance transport through the atmosphere. Part of it comes from ocean currents, as all oceans are interconnected. The Arctic is connected by the Pacific and the Atlantic. Plastic is created in different forms by users. If the water is not treated properly, it ends up in the coastal ocean and is then carried by the currents to different parts of the world. Every part of the ocean has plastic waste, including the Arctic.”
A lot of plastic accumulates in the water, and sometimes the local wind carries it up into the atmosphere and gains land.
“The Arctic is already affected by climate change, glaciers are melting. Sea routes open. This will worsen the situation. Many studies are being conducted on how this will affect climate and biology. Biology is affected in two ways. These microplastics are consumed by zooplankton (these are typically the tiny animals found in near-surface water environments). Part of their stomach is filled with microplastics and they are not getting enough nutrients. Because of this, their growth will be limited. In this case, the entire food chain is affected,” said Dr. singh.
He went on to say that these plastics have layers of paint loaded with man-made chemicals. These chemicals are then transported by marine life. Sometimes it can also be helpful.
“Let’s assume that these marine animals have harmful chemicals in their bodies and they also consume these microplastics, then these unwanted chemicals can be absorbed. All of these things require a lot of studies,” he said.