By Salam Rajesh
The other day, researchers at Pune’s MIT World Peace University (MIT-WPU) reported detecting microplastics in freshwater fish commonly consumed in the city (Express News Service/Pune, 12 October, 2026).
The MIT-WPU team conducted a detailed mapping of Pune city’s freshwater fish supply chain where they found that an approximate 37 to 40 tons of freshwater fish entered the Pune market every day, with the freshwater fish Rohu and Tilapia among the commonly traded species.
The research team observed that a significant proportion of the supply came from outside sources like Andhra Pradesh, Gujarat, Ratnagiri, Maharashtra (Mumbai) and West Bengal (Kolkata).
The analysis of the sampled fish revealed that they contained high proportion of microplastics, with both Rohu and Tilapia emerging as the ones containing maximum quantity of the tiny bits of degraded plastic particles.
The particles identified included fibres, fragments and pellets, which are among the commonly reported forms of microplastics found in freshwater environments, the MIT-WPU team reported.
Based on the detected levels and local consumption patterns, the study estimated that a person consuming an average of 250 grams of freshwater fish twice a week over 50 years could potentially ingest between 93,600 and 124,800 microplastic particles.
Interestingly, and concerning, back home in Manipur, Pallabi Borah and colleagues in 2024 examined a total of 22 fish of eight species from Loktak Lake to determine the presence of microplastics.
The species examined included Channa punctatus (Ngamu bogra, 31%), Glossogobius giuris (Nilon-nga, 5%), Oreochromis mossambicus (Tunghanbi, 9%), Pethia conchonius (9%), Pethia ticto (18%), Puntius sophore (Phabounga, 5%), Trichogaster fasciata (5%), and Trichogaster lalious (18%).
And, alarmingly, the study revealed microplastic particles contain in 91 percent of the sampled fish. The highest contamination was observed in Tilapia accounting for 51.49 percent of the detected sample (Journal of Environmental Management, Vol.358, 2024/ https://doi.org/10.1016/j.jenvman.2024.120928).
For the uninitiated, microplastics are tiny particles of plastics less than five millimetres in size, almost invisible to the naked eye. Their pervasive presence in the air we breathe, the water we drink, and the food we consume has emerged as a serious environmental concern.
Microplastics are broadly classified into primary microplastics – intentionally produced microplastics such as those found in cosmetics, and secondary microplastics – resulting from the decomposition of larger plastic materials.
Polyethylene terephthalate (PET), polystyrene (PS), polypropylene (PP), polyvinyl chloride (PVC), and polyethylene (PE) are among the most commonly used plastics in various applications such as making plastic bottles, disposable cutlery, bags, piping, and others.
The World Health Organization (WHO) reported that in 2016 cardiovascular diseases (CVDs) were one of the most prevalent non-communicable diseases in India, accounting for around 27 percent of total deaths in the country.
CVDs comprise various disorders of the heart and blood vessels, and include diseases such as hypertension, stroke, myocardial infarction (commonly known as heart attacks), and congenital heart disease.
WHO noted that recent studies conducted globally have indicated a possible link between microplastics and the severity of CVDs. Microplastics have been shown to cause cardiotoxicity, which refers to damage to the heart muscle or its function, leading to complications such as abnormal heart rhythms (arrhythmias), heart failure, and structural damage to heart tissue.
Meanwhile, health scientist Alexander Nihart and colleagues from the University of New Mexico found greater concentrations of problematic petrochemical leftovers in brain samples than in samples of kidneys and livers (Health, 04 February 2025).
The team investigated tissues samples from 52 human bodies that underwent autopsies in 2016 and 2024. Every single sample they tested contained plastic particles. While samples from livers and kidneys had similar amounts of plastic, the researchers found the brain samples had up to 30 times higher concentrations.
Combining the study findings of the World Health Organization and the University of New Mexico team, it adds up to how unknowing consumption of microscopic plastic bits through ingestion of contaminated fish flesh is leading to serious concerns on health issues, perhaps leading to immature deaths.
At this point of deliberation, it has become a matter of serious concern on defining how safe are the water of the rivers that flow through urban areas in Manipur. The Nambul River which flow through the highly urbanized Imphal City was clubbed amongst the worst polluted rivers (by select stretches) in the country, a distinction that does not merit good news for the State.
The urban pollution load, including tons of plastics waste that the river carries, is deposited directly into the freshwater Loktak Lake. And, it is reported that up to 60 percent of the total fish produce in the State comes from this wetland.
The Pune study team’s findings of high microplastics contain in Rohu and Tilapia fish sounds the warning bell for Manipur, too, given the fact that these fish species are commonly harvested from Loktak Lake, both from capture and culture fishery.
The issue is compounded with reports that recent independent studies had indicated that Loktak Lake is infested with several invasive alien species of plants and fishes, of which introduced fishes like the Asian carps and Tilapia are predominant in the wetland.
Based on this emerging health scenario locally, nationally and globally, the Manipur State Administration needs to roll up its sleeve on this perplexing issue, that is, of the polluted river water, contaminated fish (and other invertebrates), and the public health concern from consuming microplastics unknowingly.
The National Biodiversity Authority of India in 2022 had suggested removing of invasive alien species of fish – like the Common carp (Puklaobi) and Tilapia (Tunghanbi) – from the country entirely by the target year 2030 to resolve issues of native fish species decline induced by these domineering predator fishes.
This move may not be an easy one considering that both of these fish species have practically dominated the markets and the freshwater throughout the country. Whereas, with scientific findings of high microplastics contain in invasive fish species like the Asian carps and Tilapia, it is indeed high time that the State tackles the issue seriously, scientifically and in time bound strategic action plans.
