Heavy metal pollution of Bangladesh’s rivers is reaching critical levels

A new comprehensive study has revealed alarming levels of heavy metal (HM) pollution in Bangladesh’s rivers over the past two decades, calling for immediate action to control and reverse the damage.

​​​​​​​​​The study, published in the journal Environmental Science and Pollution Research on July 12, 2024, examines pollution trends in 10 heavy metals (As, Pb, Cd, Cr, Fe, Mn, Cu, Co, Ni, Zn) from 2001 to 2020, painting a dire picture of the country’s waterways.

Environmental Science and Pollution Research is an academic journal published by Springer, which is part of the German Springer Nature.

The study, conducted by a panel of experts including Debasish Pandit and Mohammad Mahfujul Haque, systematically reviewed 55 papers against the PRISMA criteria.

The results show that pollution levels in the last decade (2011–2020) were significantly worse than those observed between 2001 and 2010. In particular, the Buriganga River in Dhaka has been identified as the most polluted river in Bangladesh.

The most affected regions

The study focused on rivers in three main areas: Dhaka, Rajshahi and Chattogram, where the presence of most heavy metals was found to exceed the threshold limits set by the World Health Organization (WHO), United States Environmental Protection Agency (USEPA). ) and Bangladesh Department of Environment (DoE).

The average concentration of arsenic (As), lead (Pb), cadmium (Cd), chromium (Cr), iron (Fe) and manganese (Mn) exceeded the permissible limits during all three seasons, with the highest contamination occurring in summer. months

The Buriganga, which runs through the heart of Dhaka, has been heavily affected by industrial activity, including leather, textile and electroplating factories.

These industries dump untreated effluents filled with heavy metals directly into the river, creating an environmental crisis that has worsened over the years.

The main sources of pollution

The study revealed multiple sources of TM pollution, which include natural weathering processes as well as anthropogenic activities. Fertilizers and pesticides from agriculture, mining, electroplating, textiles, coal and industrial wastes such as batteries and paints are major contributors to river water pollution.

These pollutants accumulate in the ecosystem, posing a threat to aquatic life, human health, and the environment.

Urgent need for action

The study highlights the urgent need for stronger legislation and more effective enforcement to curb pollution.

Its recommendations include continuous monitoring, comprehensive research and information campaigns to inform industry and the public about the importance of protecting water resources.

Experts are calling for an integrated approach to river basin planning and management that focuses on sustainable solutions. Without immediate intervention, Bangladesh’s rivers—vital to the livelihoods of millions—could be irreparably damaged.

“High levels of toxic heavy metals in our rivers, especially in regions like Dhaka, pose a serious threat to public health and the environment,” said one of the co-authors, Mrityunjoy Kunda. “To protect future generations, we must act now.”

The study serves as a vivid reminder of the escalation of environmental problems in the Anthropocene era, when human activity has become the dominant influence on the planet’s climate and ecosystems. Protecting rivers in Bangladesh is not only a matter of biodiversity conservation, but also of ensuring the country’s long-term water security and public health.