INTERVIEW - Bangladeshi researcher warns of threat to river fish from microplastics

By SM Najmus Sakib

DHAKA, Bangladesh (AA) - A team of Bangladeshi researchers from Jahangirnagar University (JU) recently found microplastics in urban river fish after collecting samples from nearby kitchen markets on the outskirts of the capital Dhaka.

The saying "fish and rice make a Bengali" has once again been called into question due to toxic plastic pollution following the study, which found that 73% of the fish examined contain microplastics.

The plastic polymers found include high-density polyethylene, polypropylene-polyethylene copolymer, and ethylene-vinyl acetate. The study has already been published in the international peer-reviewed scientific journal Science of the Total Environment.

Despite a government ban in place since 2002, the rampant manufacture of polybags has continued unabated in Bangladesh. A recent study found that 87% of the country's polythene and plastic waste is not disposed of through environmentally sound management.

Research team leader Shafi Mohammad Tareq is a professor at JU's Department of Environmental Sciences and a fellow of higher education academy, UK. He works in academic fields, including pollution and health risks, waste and wastewater, emerging pollutants, and climate change.

The other two members of the team are another JU professor Fahmida Parvin and graduate student Shumya Jannat studying at the same institution.

In an exclusive interview with Anadolu Agency, Tareq explained his team’s research purpose and findings. He also spoke about the emerging crisis in Bangladesh over the challenges on the availability of potable and usable water as a consequence of unabated and uncontrolled plastic and river pollution.

Following are excerpts from the interview, and edited for clarity:

Anadolu Agency: What were the purpose and findings of the research?

Tareq: We live in a "plastic era," and the urban rivers and water bodies are being highly polluted. Therefore, we wanted to know if there is any presence of unusual content in the stomachs of fish living in urban rivers and water bodies.

We examined 48 fish of 18 local river species and found the presence of different types of toxic microplastics in the stomachs of 15 species. The research team also found some types of microplastics used in human hair shampoo and body lotions.

These fish are collected from the Savar and Ashulia kitchen markets, and fish in these markets come from among the major Dhaka rivers and water bodies including the rivers Buriganga and Turag.

We, in our JU lab, also examined the phases of swallowing plastic contents from the mouths of fish to their stomachs. We saw the microplastics stored not only in the stomach but also in other parts of the fish's bodies. Subsequently, these toxic items enter the human body when we eat these fish.

Q: What do the research findings say about the effects on life and the environment?

Tareq: When fish swallow plastic items, their brain cannot function normally and it creates obstacles for healthy growth. Microplastics directly affect the reproduction capacity of the fish. It potentially can reduce reproduction. Therefore, fish species could be extinct finally.

As far as the human body is concerned, it does not immediately show signs of illness when we eat these contaminated fish. But it certainly and slowly affects the human body, including developing cancer cells and causing the reproduction organs and body functions to be less active.

Consuming these affected fish could create a hormonal imbalance and disorder in the human body.

Q: What causes the urban rivers to become so polluted?

Tareq: We don’t have any well-designed waste management system in the country. For so many years, we could not set up a central waste management system. What we have is too poor to become environmentally friendly and sustainable.

The city authorities dump city waste into some landfills outside the capital, but those don’t have proper management and monitoring systems, they are rather polluting those areas further.

Bangladesh is the 10th worst country in waste management and dumps waste in the Bay of Bengal. In 2020, microplastics were found in marine fish and living creatures in the Bay of Bengal.

Recently a number of sea whales, dolphins were found dead onshore, which certainly means the Bay of Bengal is being polluted highly. Such pollution is also an increasing threat to the country’s blue economy, which offers the country huge prospects and potential.

So we have to engage people in the process of waste management, introduce waste management awareness from the primary education curriculum, and train citizens from childhood to keep our surroundings clean. Otherwise, no waste management framework would work properly.

Q: What are the consequences and correlation between plastics and river pollution?

Tareq: The urban rivers in Bangladesh, certainly in the capital Dhaka, have already been out of use in the last 10 to 15 years. We no longer can use Dhaka's main Buriganga River, which flows past the southwest outskirts of the capital city, because it can't be purified due to the high amount of pollutants.

Almost 80% of the pollutants in the city rivers were plastics.

In my earlier joint research, we found the presence of whitening detergent in the country’s longest Padma River water. It’s clearly a worrying sign that shows how much the country’s factories and garment industries have been polluting the river waters with a growing threat towards usable waters.

Now the city authorities are thinking of bringing water from outside the capital, which will require huge cost and effort.

Meanwhile, the groundwater level in Dhaka continues to fall, and in the next 10 years, it will become tough to drag water or go out of order. Water will be the main challenge in urban life, and we would not be able to bear the cost of it.

We need a comprehensive policy from the government end to address the emerging threat.

Q: Bangladesh is a riverine country, but its major rivers are transboundary, having the main sources from India. Are Bangladeshi rivers victims of transboundary river pollution?

Tareq: I, along with seven other researchers from eight South Asian countries, have recently worked on Asian major rivers. We examined the Ganga River, a transboundary river of Asia that flows through India and Bangladesh and ends at the Bay of Bengal.

We closely examined the major river, since it rises in the western Himalayas. We found less pollution near the source of the river (at the beginning points of the western Himalayas and subsequent points in India) and gradually high pollution in low-lying river points.

We may consider, for proper understanding, the river as a funnel. Therefore, all the pollutants continue to be stored at the bottom points, and Bangladesh remains at the bottom point of the transboundary Ganga River.

Whatever pollution usually happens in transboundary rivers in India, it ultimately goes down to the Bay of Bengal through different river points. Therefore, we need a joint working group with the participation of neighboring countries in order to protect rivers from pollution and therefore keep lives and the environment alive.