Microplastics in Pune fish have been detected in commonly consumed Rohu and Tilapia, according to ongoing research by MIT World Peace University (MIT-WPU), raising questions about how plastic pollution moves through freshwater ecosystems and enters the city’s food supply.
The study is being conducted by Simran Singh, a PhD scholar in MIT-WPU’s Department of Environmental Studies, under the guidance of Dr Soma Mishra. Funded through the university’s Seed Grant, the research is examining the occurrence, characteristics and possible sources of microplastic contamination in commercially consumed freshwater fish.
Researchers began by mapping Pune’s freshwater fish supply chain rather than examining only retail markets. The survey covered major wholesalers and distributors, which the study identifies as important entry points for fish supplied to the city. Pune was divided into four geographical zones, and the researchers interviewed 26 wholesalers and distributors across the city.
Based on the survey, approximately 37-40 tonnes of freshwater fish enter Pune’s market every day. Rohu and Tilapia are among the commonly traded species. A significant share of the supply comes from aquaculture systems, while consignments also reach Pune from Andhra Pradesh, Gujarat, Ratnagiri, Mumbai and Kolkata. The findings underline the interstate nature of the city’s freshwater fish distribution network.
Laboratory testing of the fish samples identified microplastics in the form of fibres, fragments and pellets. These are commonly reported categories of microplastics found in freshwater environments. The researchers are continuing detailed quantitative analysis and polymer characterisation to establish the properties of the particles detected in the samples.
Based on the detected levels and local consumption patterns, the study estimates that a person eating 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. The researchers have cautioned that this particle count cannot be directly equated with the number of plastic bottles or other plastic items.
The potential significance of the particles depends on factors including their size, polymer composition and associated contaminants. The ongoing analysis is expected to provide more information on these characteristics. The study does not present the particle estimate as a direct measure of human-health impact.
The research is intended to establish baseline scientific data on freshwater microplastic pollution in Pune, a rapidly urbanising city. It is also examining the pathways through which microplastics may move from freshwater environments into the food chain. The researchers said the work could support evidence-based approaches to plastic waste management, wastewater management, freshwater ecosystem conservation and food safety.
The project received recognition at the National Scientist Round Table Conference, where Singh recently received the Third Prize for her poster presentation. “Plastic pollution is no longer just an environmental issue; it is becoming a food-chain issue,” Dr Mishra said. She added that understanding where microplastics originate, how they move through freshwater ecosystems and how they reach fish is essential for developing informed policies and sustainable solutions.
The next stage of the doctoral research is the completion of quantitative analysis and polymer characterisation, which will provide further detail on the particles identified in the fish samples and their possible contamination pathways.
