- Fears of possible chemical and plastic contamination of seafood and salt have driven down consumption of fish in Sri Lanka, the main animal protein for the country’s majority Buddhist population.
- Consumers are concerned that pollutants from a cargo ship that caught fire and sank off Colombo in May could end up in the fish they eat, and the government has not given any reassurances while it continues to investigate the incident.
- Experts say there are reasons to be concerned but note that Sri Lankans are already eating seafood and salt that’s contaminated with heavy metals and microplastics.
- They say the ship sinking should serve as impetus for the government to take measures to reduce marine pollution in general and set guidelines for safe levels of seafood consumption.
COLOMBO, Sri Lanka — Sunitha Rathnayake, a homemaker in southern Sri Lanka, was down to the last of her salt and planned to order some more from an online grocery service at the end of June. But she soon found out that salt was out of stock at the main supermarkets, with shoppers panic-buying the condiment; they were apparently fearful that future supplies of salt would be contaminated by pollutants from the sunken X-Press Pearl container ship.
Sunitha had to cook without salt for several days until the suppliers had restocked, but now she says she’s fearful about buying fish in light of the maritime disaster in May. Like many Buddhist households in Sri Lanka, the Rathnayake family doesn’t eat meat, so fish is the only animal protein available at home.
Fears about seafood being contaminated by the plastics and toxic chemicals that were on board the Singapore-flagged X-Press Pearl when it caught fire and sank off Colombo have affected a wide swath of Sri Lankan society. “As my regular buyers stop consuming fish, I had to pedal extra kilometers trying to sell the daily quota of fish I bring to sell,” says Asoka Sumathi, a fishmonger who goes door to door by bicycle. He says he often had to return with unsold fish during the weeks soon after the ship’s sinking, and his business hasn’t fully recovered yet.
Fish vendors at Sri Lanka’s main fish market in Peliyagoda, northern Colombo, say prices have dropped due to decreased demand. In an attempt to prove that the fish is safe to eat, some vendors ate raw fish in front of the media.
At the same time, there’s been neither confirmation nor reassurance from the government on the issue. Susantha Kahawaththa, director-general of the Department of Fisheries and Aquatic Resources (DFAR), says that no mass fish deaths have occurred due to the accident. However, following the sinking, DFAR and the National Aquatic Resources Agency (NARA) are still collecting dead fish samples to test for possible contamination linked to the incident, and have so far not found anything to establish the link.
“There can be short- to long-term impacts to fish due to the pollution caused by the sunken ship,” says Ruchira Cumarathunga, emeritus professor of fisheries at the University of Ruhuna. He says the sinking coincided with the spawning period for fish species. “As the ship was carrying a large number of chemicals, we do not clearly know how they would react and the chemicals can pass through small to larger fish through the food chain, and this requires vigilance and monitoring of fish for several seasons,” Cumarathunga tells Mongabay.
Experts say some fish species may be more vulnerable to the pollution than others. Large quantities of plastic beads, or nurdles, fell off the X-Press Pearl and into the sea after it caught fire. Another threat comes from the sinking of the vessel, whose carcass may affect bottom-feeding and grazing fish such as some coral fish species, Cumarathunga says.
While many worry about the possible contamination of fish due to the ship accident, researchers say some fish species already have chemicals such as mercury, lead, cadmium and arsenic, along with microplastics, in their bodies due to oceanic pollution in general.
A 2018 study by NARA showed that swordfish and yellowfin tuna had high levels of mercury and cadmium, and dried shark meat had very high levels of pollutants, says Kolita Jinadasa, a senior scientist. Another study has shown that pollutants from industry and other sources have impacted seaweeds in some sites in Sri Lanka.
Risk-benefit analysis
The pollution caused by the X-Press Pearl’s sinking may have future impacts, but this shouldn’t deter people from consuming fish, as it still offers high nutrition value, experts say.
Jinadasa recommends setting safe limits for the consumption of fish through a risk-benefit analysis. He says Sri Lanka should establish guidelines for provisional tolerable weekly intake (PTWI), to allow the consumption of potentially harmful contaminants in certain foods at low enough levels that can be sustained over a lifetime without health risks.
At the same time, however, Sri Lanka should take urgent measures to monitor its marine pollution levels and set up a periodic monitoring mechanism, Jinadasa tells Mongabay. Without baseline data, he says, it’s difficult to quantify the impacts of an accident like the X-Press Pearl sinking, and thereby take informed decisions.
Other studies have identified the prevalence of microplastics in fish species consumed in Sri Lanka. A recent study done at an estuary in southern Sri Lanka found microplastics in the gut and muscles of Commerson’s anchovy (Stolephorus commersonnii), a small fish widely consumed across Sri Lanka. A marine environment survey conducted by the Norwegian government research vessel Fridtjof Nansen also found microplastics in Sri Lankan waters.
An April 2021 study shows that more than 1,000 rivers account for 80% of the plastic waste that reaches the ocean via rivers. It also names Sri Lanka as among the top 20 ocean polluting countries.
Experts say the chance of chemicals leaked from the X-Press Pearl contaminating salt production is low, as the long manufacturing process would tend to mitigate that risk. However, microplastics have already been found in commercial salt in Sri Lanka, according to a recent study, which indicates that some salterns are more prone to microplastic contaminants.
Pollution of seafood also has severe trade implications for Sri Lanka, which exported some $300 million worth of fish in 2019, according to DFAR. Many export markets have strict regulations in terms of level of pollutants such as mercury and cadmium, and if the current rate of marine pollution continues, Sri Lanka risks losing this source of foreign exchange.
As the country grapples with ocean and river pollution, and the X-Press Pearl incident adding a new layer to an increasingly complex problem, experts have reiterated the need for long-term action plans to ensure seafood safety. The maritime disaster should be the impetus to drive such a program with set targets, Jinadasa says.
Citations:
Jayasinghe, G. D., Sandaruwan, K. P., Silva, D. W., & Jinadasa, B. K. (2018). Total diet study approach in estimating mercury and cadmium levels using selected fish: A case study from Sri Lanka. Ceylon Journal of Science, 47(3), 275. doi:10.4038/cjs.v47i3.7534
Meijer, L. J., Van Emmerik, T., Van der Ent, R., Schmidt, C., & Lebreton, L. (2021). More than 1000 rivers account for 80% of global riverine plastic emissions into the ocean. Science Advances, 7(18), eaaz5803. doi:10.1126/sciadv.aaz5803
Praboda, M. W., Egodauyana, K. P., Wijethunga, H. N., Abeygunawardana, A. P., Senevirathna, J. D., & Thushari, G. G. (2020). Occurrence of microplastics in gut and muscles of Commerson’s anchovy in Madu-Ganga Estuary of Southern Province, Sri Lanka. Conference session presented at International Research Conference 2020, Uva Wellassa University of Sri Lanka. Retrieved from http://www.erepo.lib.uwu.ac.lk/handle/123456789/5649
Banner image of a variety of seafood. Image by PublicDomainPictures via Pixabay.