Dhaka textile plants spewing microplastic into waterbodies

SM Najmus Sakib
Fashion industries in Dhaka and adjacent textile hubs are leaking microfibres into waterways and the environment, according to a new study that finds treatment plants are ineffective at removing the pollutant.
This leakage poses a greater risk to the environment, water bodies and food supplies, as the study found evidence of microfibres in factory wastewater and sludge.
Textile Effluent Treatment Plants (ETPs) are used to remove harmful materials and chemicals from wastewater so it can be reused or released safely into the environment. However, the study identifies them as a primary source of microfibre pollution in aquatic environments.
The studied ETPs showed a microfiber removal rate of between 23.52 per cent and 82.19 per cent, which is insufficient to minimise pollution.
Textile industries in Dhaka, Gazipur, Narayanganj and Narsingdi were included in the study. This is believed to be the first evidence of microfibres in textile wastewater and sludge in Bangladesh.
The study investigated the abundance and removal efficiency of microfibres in the ETPs of 11 woven, knit and denim industries. Fibres were the most common shape and most were between 0 and 100 ?m in size.
The denim industry was found to shed more microfibres or polymers than the knit and woven industries.
The study, titled 'Microfibre prevalence and removal efficiency of textile effluent treatment plants in Bangladesh', was published in the peer-reviewed Journal of Hazardous Materials Advances in May this year.
It was funded by the University Grants Commission (UGC) and Bangladesh University of Textiles (BUTEX).
There are two main types of fibre: natural (from plants and animals) and man-made (including natural polymers, synthetic fibres, and inorganic fibres).
Around 60 per cent of textile products are made from synthetic materials such as polyester and nylon.
Md Morshedul Haque, the corresponding author of the study and a lecturer in the Department of Environmental Science and Engineering at BUTEX, told The Financial Express that the various stages of textile production, such as de-sizing, scouring, bleaching, dyeing, printing and washing, can all release microfibre particles into the ETP.
"ETPs in the factories studied were unable to remove microfibres effectively, leading to leakage into the environment. Furthermore, these microfibres cannot degrade in soil once released by ETPs," Mr Haque added.
Local industry ETPs are primarily designed to treat organic matter. Therefore, we need to develop effective ETPs to address these emerging pollutants, he suggested.
The research findings were analysed at the environmental department laboratory of Jahangirnagar University.
Professor Shafi Mohammad Tareq, a teacher at the Department of Environmental Sciences at Jahangirnagar University and co-author of the study, told the FE that a key motive of the research was to identify the source of microplastics or microfibres that are already harming the environment.
"We conducted other studies that found microplastics to be the top source of pollution in water bodies across the country. This research shows that the fashion industry is another major source of microplastic leakage into the environment," he added.
The researchers said the findings would help identify the challenges needed to minimise microfiber pollution from industry and improve ETP systems.
"We live in a plastic age and we cannot abandon plastics altogether. Our work focuses on finding environmentally friendly ways to control plastic use and develop efficient wastewater treatment mechanisms," Professor Tareq suggested.
Synthetic fibre released from household laundry has already gained global attention. Textiles are a major source of microfiber pollution worldwide, through both industrial processing and products themselves, according to the study.
Microfibres, also known as microplastic fibres, synthetic fibres, or even chemical fibres, are defined as environmental pollutants when they are less than 5mm in length.
Researchers reported that 164 litres of groundwater were used to process 1kg of textile materials, generating 119 litres of wastewater per kilogram.
The ultimate fate of this partially treated or untreated wastewater is often to nearby aquatic environments.
"These ineffective ETPs allow microfibres to enter water bodies and ultimately soil. Various studies have now found microplastics in vegetables and even human blood," Mr Haque said citing the ecological impact of the study.
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