Micro-plastic and seafood

Sri Lanka’s garbage problems have a new dimension. Researchers have found micro-plastic particles in coastal waters off Sri Lanka with the highest concentration recorded in the North West and the lowest in the North East. This indicates that not only should Sri Lanka formulate policies to ensure sustainability of its marine resources, but may also have to consider micro-plastic contamination in seafood.     

Micro-plastics include broken down plastic waste, synthetic fibres and beads found in personal hygiene products. They are known to harm marine life, which mistake them for food, and can be consumed by humans too via seafood, tap water or other food. The risk to people is still not known, but there are concerns that micro-plastics can accumulate toxic chemicals and that the tiniest could enter the bloodstream. 

The scale of global micro-plastic contamination is only starting to become clear. In Paris in 2015, researchers discovered micro-plastic falling from the air, which they estimated deposits three to 10 tonnes of fibres on the city each year, and that it was also present in the air in people’s homes.

Researchers from the Institute of Marine Research (IMR) Norway and the National Aquatic Resources Research and Development Agency (NARA) of Sri Lanka found the highest concentration of 0.89 particles per square meter of sea water in coastal waters of the Gulf of Mannar area.

The results reveal that the waters around Sri Lanka are contaminated with micro-plastic, and the vast majority of micro-plastic found are in the secondary category, indicating that the packaging material, industrial applications, and fishing gear are major sources. The highest concentrations were found in the off North Western region of Sri Lanka. This region was highly polluted with micro-plastics, compared to other regions, while the North East coast and the South coast showed the lowest number of micro-plastic particles in the samples.

The lowest concentration of 0.21 particles sq. m was found in the North East coastal waters. A Norwegian research vessel made a broad ecological survey for Sri Lanka’s coastal waters during June and July 2018. The survey was during the South West monsoon season and the research was based on its findings. 

Almost 300 million tonnes of plastic is produced each year and, with just 20% recycled or incinerated, much of it ends up littering the air, land and sea. It has been estimated that 8.3 billion tonnes of plastic has been produced since the 1950s, with researchers warning that plastic waste has become ubiquitous in the environment. 

Clearly more work needs to be done to investigate possible human dietary intake of micro-plastic contamination in fish and shellfish and which types of micro-plastic particles are likely to be most hazardous. Also needed is a better understanding of the ability of micro-plastic to absorb pollutants, and greater information on the ecosystem effects of micro-plastic in terms of the extent to which they undermine ecosystem productivity and biodiversity. 

For Sri Lanka already struggling under a massive garbage problem, proper recycling and disposing of plastics has become even more urgent. The NARA report also found rapid dwindling of fish stocks around Sri Lanka and warned that overfishing along with pollution could deplete resources much faster than thought earlier. If Sri Lanka is serious about preserving its seafood industry, policymakers and private sector stakeholders will have to start paying attention to these challenges.