India’s marine debris database remains scattered, making it difficult to identify true hotspots and frame effective policy, says KUFOS Vice Chancellor A Biju Kumar.
Kumar says India needs local studies on microplastics, nanoplastics, plastic degradation and emerging contaminants in Indian coastal waters and marine habitats.
A national research consortium, stronger solid-waste management and incentives for fisherfolk are needed to tackle marine litter, he says.
India lacks a comprehensive baseline on marine litter, making it difficult to identify true hotspots, assess ecological impacts and design targeted policy, says A Biju Kumar, vice chancellor of the Kerala University of Fisheries and Ocean Studies.
In this interview, he tells Down To Earth why India cannot rely only on studies from western countries, how ocean currents carry debris even to remote islands, and why a national research consortium, stronger solid-waste management and incentives for fisherfolk are needed to tackle marine litter.
Akshit Sangomla (AS): The first step towards understanding marine litter is to know the scale of the problem. What is the scale of marine litter along the Indian coastline?
A Biju Kumar (ABK): The general database on marine debris in India remains scattered. If you want to carry out a hotspot analysis, it would be based on already published work. Such information is available to an extent. Major hotspots appear to be along Kerala and Tamil Nadu, but this may not be the true picture, primarily because the analysis is based on published work from specific states.
Only through a comprehensive assessment of the amount of marine debris and its composition across India can we have a baseline dataset. Such a study is currently lacking, but it is essential for any kind of planning. We need to understand the points of marine litter pollution, including the contribution of the ocean sector and litter coming from land, mostly because of the mismanagement of solid waste.
AS: Most of our hypotheses around marine litter are based on studies done in western countries. What is the significance of conducting studies along the Indian coastline and in the country’s fisheries sector?
ABK: Looking at the international perspective, we have the Plastics Treaty coming up. There are also international regulations on the use and transport of plastic and hazardous materials. In that context, we need to frame our studies based on local perspectives.
The kinds of pollutants and emerging contaminants associated with plastics have to be documented specifically. The degradation of marine debris in the ocean is also entirely different in India. Our hypotheses are based on western studies, where the emerging contaminants and their cocktail are entirely different from the chemicals in India.
India is also becoming a consumer society, so the quantity and types of single-use plastic are different for us. Many plastic materials used in India are also manufactured within the country. Therefore, we need studies on the photodegradation of plastics in the ocean and the emerging contaminants in Indian coastal waters.
Once we have an understanding of this, we can move to the cocktail impact on marine organisms. Then we can also have mesocosm experiments to determine the impacts of specific chemicals in marine debris, especially those coming from plastics, on marine biota.
Many western experimental studies are also conducted on animals from those habitats, many of which are from much colder waters. The response of that marine fauna to plastic particles is entirely different from the response of fauna in Indian marine habitats. We need to conduct studies on the impacts of microplastics and nanoplastics on animals present in the Indian marine environment.
AS: What are your recommendations for detailed studies on the impacts of microplastics and nanoplastics on marine mammals?
ABK: If you specifically want to understand the impacts of microplastics and nanoplastics on marine mammals, both laboratory experiments and mesocosm studies in real ecosystems are required.
There is a lot of marine diversity along Indian coastal waters. Along the Kerala coast, we do not have coral reefs. Along the south-eastern coast and the islands, there are coral reefs. So the scenarios are completely different for each coastal state.
I would recommend a larger consortium in India, where scientists can conduct experiments in different habitats or biomes, find out the impacts of microplastics and nanoplastics on marine organisms, and combine these studies to come up with a strategy.
For example, the European Union has come out with such a strategy to mitigate various contaminants and their threats. The ultimate aim is to go for zero litter or debris. If we want to arrive at that point, we need a stronger database.
In a recently conducted Indo-European call for mitigating contaminants coming from plastics, the database was highlighted as a major problem. Europe has gone ahead with its strategy because it already has a strong database, especially on the ecotoxicology of pollutants from plastics. In India, we have some fragmentary studies, but that is not strong enough for baseline data. Experimental proof is required to arrive at policy conclusions.
AS: The accumulation of marine litter in the ocean is also shaped by ocean circulation. How much do we understand about this correlation?
ABK: There is no wide-scale study in India on such correlations, but we know that there are garbage patches in the seas around India. Gyres are not present in the immediate coastal waters around the country, but ocean currents do affect the distribution of marine litter.
For instance, you can look at the distribution of litter across various islands to understand how this movement is happening. We conducted a recent study in the Lakshadweep Islands, where we found that even on remote islands with no human habitation, the amount of marine litter deposition was much higher.
Essentially, this means that winds and ocean currents carry litter from distant sources even to the remotest areas, and these areas are not safe from this problem. Understanding the flow of debris and its deposition is also essential for policy decisions.
AS: This is also related to the transboundary nature of marine litter across land, ocean and atmosphere. How do we understand this characteristic of marine litter?
ABK: India has already drafted a marine litter policy, which talks about how to conduct research and other strategies. To implement the policy, we need a national consortium rather than a few institutes taking it up.
An all-India study based on the priorities stated in the marine litter policy is needed. We also need to think about how to address the International Plastics Treaty. If we have a policy framework and outlook, it will help us frame our research questions.
AS: What can be done to prevent marine litter from entering the sea, and what can be done about litter that has already entered the sea?
ABK: For a solution to India’s marine litter problem, we have to start from land. It has to begin with fine-tuning the existing solid-waste management system in the country. The main conduits for litter entering the sea are rivers, which is similar elsewhere in the world.
There are two methods to stop debris from entering the sea through rivers. The first is based on mechanical barriers that prevent litter from entering the sea to an extent. The second is incentivising fisherfolk who go to sea to bring back the litter they generate, instead of throwing it into the sea. They can also bring back the trash collected in their trawl nets, which can then be processed and used for multiple purposes, including road tarring.
Such an experiment was conducted in Kerala through the Suchitwa Sagaram project. The project is not working well right now because the incentive part is lacking. The fisheries and environment departments in India can incentivise fisherfolk who bring back litter, mainly plastic, from the ocean. If such a system is established, it will help manage marine debris that is already in the ocean.
Another major source of litter is the tourism sector, where specific controls and directions for the use of single-use plastics should be put in place. Ultimately, we need to move towards a circular economy. Management upstream — on land and in rivers — and downstream — in seas and oceans — will help us tackle the marine litter problem in India.
Shreya KA (SKA): You had mentioned earlier that the carcasses of stranded marine animals could be used for research. Can you elaborate on that?
ABK: India needs a programme for monitoring marine debris in its coastal waters. One of the easiest ways is to monitor whatever is landing in fishing harbours. Another source on which we have very little information is marine megafauna, such as turtles, whales and dolphins.
There are quite a lot of strandings of these animals along the Indian coast, and many of them are ultimately buried because they are scheduled species. All these animals can provide data for plastics management as well as wildlife management.
I would suggest that all stranded animals should be used for post-mortem studies, especially to look at the impacts of plastics and microplastics on their health and longevity. We generally do not know the reasons for their strandings and deaths. A monitoring network along the Indian coast would help collect a huge amount of data.
SKA: What are the biggest challenges in managing marine litter in India?
ABK: Data is definitely a big challenge, because there is not enough of it to frame policies. The second is competition among institutions, which should not be happening. Many institutions end up doing the same work in the same area. This is all public money, so all institutions should get together, divide the work and do it.
A national consortium will help with this coordination and collaboration among different institutions. The main jurisdiction for marine litter falls under the Ministry of Environment, Forest and Climate Change, as the Central Pollution Control Board is also under it. But when it comes to the oceans, the Ministry of Earth Sciences also has a role, with institutions such as the National Centre for Polar and Ocean Research and the National Institute of Oceanography already working on marine litter.
SKA: A lot of what is happening in the oceans is not visible to most people. Would you like to talk about the gravity of the problem, especially for people who are not thinking much about this issue?
ABK: We have publicised a lot of information from western countries on deaths of turtles or dolphins due to marine litter. But we do not have specific examples from India on this. That does not take away from the fact that marine litter is a big problem in Indian waters, especially up to a depth of 50 metres, where we have documented the impacts.
Plastics have choked entire rocky reefs along the Kerala coast, and this is a major concern for marine wildlife. Realising this will generate public interest. When you go to the shore, you enjoy the sea and come back, but you do not realise what is happening just beneath the sea’s surface.