High levels of harmful chemicals found in dry fish in Chennai: study

A recent study has raised concerns about the consumption of ‘Karuvadu’ or dry fish, a popular delicacy in Chennai. The research reveals that 22 types of dry fish from various parts of the city contain significant amounts of harmful chemicals.

The study, conducted by the Department of Zoology at The New College, found alarming levels of cadmium, lead, and cobalt in several varieties of dry fish, including sear fish, sardines, cured tuna, and anchovies. These levels far exceed the safe limits set by the World Health Organization (WHO).

Chennai’s dry fish contain harmful chemicals

The research suggests that excessive consumption of dried fish could potentially lead to cancer. The journal Environmental Science and Pollution Research published the study titled ‘Risk assessment on human health due to consumption of dry fish in Chennai city of Tamil Nadu state in India: A baseline report.’

Researchers found that lead levels in dried fish ranged from 32.85 mg per kg to 42.09 mg per kg, significantly higher than the WHO’s permissible limit of 2.17 mg per kg. They also found that cadmium levels ranged from 2.18 mg per kg to 3.51 mg per kg, exceeding the WHO safe limit of 0.05 mg per kg. They found cobalt concentrations surpassed the safe limit of 1.13 milligrams per kilogram, ranging between 2.95 mg per kg and 9.55 mg per kg.

Mohamed Saiyad Musthafa, an assistant professor of zoology at The New College and one of the authors of the study, stated that they wanted to investigate the presence of heavy metals in dried fish, following previous studies on fresh fish in Chennai. They selected the most commonly consumed dried fish in the city for their research, as dried fish is a staple food for fishermen and coastal residents.

Musthafa explained that the high levels of harmful chemicals found are due to marine pollution. E-waste, which contains components of cadmium and lead, is also discarded into the sea in North Chennai.

Lead levels in dry fish were found to be 32.85 mg per kg to 42.09 mg per kg, while the permissible limit set by WHO is 2.17 mg per kg.

Poor-quality salt in curing fresh fish

Phytoplankton accumulate these heavy metals, which zooplankton and smaller fish then consume. Darwin Annadurai, an environmental engineer and founder of Eco Society, noted that this process increases the concentration of heavy metals in the tissues of the last animal in the food chain. If we consume fish contaminated with heavy metals, they can accumulate in our bodies, potentially leading to poisoning or cancer.

Musthafa also highlighted that another source of contamination is the use of poor-quality salt in curing fresh fish. Annadurai emphasized the need for regular sampling of fresh and dried fish by the food safety department to monitor these contaminants.

The use of poor-quality salt in curing fresh fish is another contributing factor to this pollution. The study’s author, Mohammed Syed Mustafa, and environmental engineer Darwin Annadurai emphasize the need for frequent sampling of fresh and dried fish by the food safety department to ensure consumer safety.

The high levels of these harmful chemicals are attributed to marine pollution and e-waste dumping into the sea in North Chennai. These heavy metals accumulate in phytoplankton and subsequently enter the food chain, leading to an increase in their concentration in fish tissues.

Keep Reading

• UAE is using bots to get support on COP28
• How UAE is making the Cop28 climate summit a joke?
• Everything We Know About COP 28 in Dubai This Year
• India urgently requires $50-100 billion for climate financing: Experts

Follow Ground Report for Climate Change and Under-Reported issues in India. Connect with us on Facebook, Twitter, Koo App, Instagram, Whatsapp and YouTube. Write us on [email protected].