Context: Recently, the Council of Scientific and Industrial Research-National Institute of Oceanography (CSIR-NIO) has published a study titled “Microplastics in seafood as an emerging threat to marine environment: A case study in Goa”.

Key major findings

• The study indicated the presence of microplastics in water, sediment and biota (local animal and plant life) from the estuary.
• It highlighted that the levels of microplastics found in fish and other seafood samples from the Sal Estuary in Goa are worrisome.
• The estuary is a valuable source of oyster, finfish and shellfish species.
• The average abundance of microplastics is significant which is comparable to the microplastic abundance in water from the Netherlands and China and in sediments from China and Nova Scotia (Canada).

Sources

• A similar signature of polymers in water and sediment, and in seafood suggests that human activities in the densely populated area around the estuary might be the leading source of microplastic contamination.
• Fishing activities may also contribute to the microplastic pollution in the estuary.

Concerns

• The presence of microplastics in the gastrointestinal tract of finfish may pose an additional threat to these fishes due to the leaching of chemicals.
• An abundance of various microplastics in bivalves (shellfish) poses risk to humans because bivalves are mostly consumed as a whole.
• The widespread contamination by plastic particles is seriously impacting the coastal marine biota.

Suggestions

• It calls for robust management strategies to stop it.

Microplastics

• According to the US National Oceanic and Atmospheric Administration (NOAA), microplastics are not a specific kind of plastic, but rather any type of plastic fragment that is less than five millimetres in length.
• There are two types of microplastics which persist in the environment at high levels, particularly in aquatic and marine ecosystems.

Primary Microplastics

• These are any plastic fragments or particles that are already 5.0 mm in size or less before entering the environment.
• These include microfibers from clothing, microbeads, and plastic pellets (also known as nurdles).

Secondary Microplastics

• These are microplastics that are created from the degradation of larger plastic products once they enter the environment through natural weathering processes.
• Such sources of secondary microplastics include water and soda bottles, fishing nets, and plastic bags.

Concerns

• Water Source Contamination: Microplastics are already known to contaminate the world’s surface waters.
• Impact on Marine Life: Plastic in the water ends up in the guts and gills of marine life, exposing the animals to chemicals in the plastic, which can lead to biomagnification. It also reduces the growth and reproductive output in marine animals
• Biomagnification is any concentration of a toxin, such as pesticides, in the tissues of tolerant organisms at successively higher levels in a food chain.
• Impact on Blue Economy: The perception of contamination by plastic and the chemicals associated with plastic may decrease the value of fisheries and aquaculture products.
• Risk of Marine Species Invasions: The longevity of plastic in the ocean is increasing the potential for species to disperse far and wide and increasing the risk of marine species invasions.
• Lack of Recycling Facilities: Most of the microplastic particles are synthetic fibres, which come from clothes, fishing nets, toothbrushes, etc. It shows the absence of recycling and reusable facilities for proper disposal of plastic waste.

Suggestions

• Recycling and Reuse: There is a need to reduce the use of single-use plastics such as multi-layer packaging, bread bags, food wrap, and protective packaging which are major and dangerous sources for plastic pollution.
• Economical Support: The economical support including tax rebates, research and development funds, technology incubation, public-private partnerships and support to projects that recycle single-use items and turn waste into a resource can be enforced.
• More Usage of Sustainable Options: The expansion of the use of biodegradable plastics or even edible plastics made from various materials such as bagasse (the residue after extracting juice from sugarcane), corn starch, and grain flour should be encouraged.
• Effective Implementation of Policies: Existing international legally binding instruments should be further explored to address plastic pollution.

The most important is the 1972 Convention on the Prevention of Marine Pollution by Dumping Wastes and Other Matter (or the London Convention), the 1996 Protocol to the London Convention (the London Protocol), and the 1978 Protocol to the International Convention for the Prevention of Pollution from Ships (MARPOL).