A writ petition was filed with the High Court on Monday seeking an investigation into the presence of harmful microplastics in 26 out of 34 toothpaste samples available in Bangladesh market.

Supreme Court lawyer Md Abdullah Al Mamun filed the writ petition with the HC bench concerned on Monday after a recent study detected microplastics in most of the tested toothpaste samples.

Secretaries to the ministries of Health, Environment and Commerce, the Bangladesh Standards and Testing Institution (BSTI), and the Directorate of National Consumer Rights Protection have been made respondents to the writ petition.

According to the study, 26 of the 34 toothpaste samples tested contained between 20 and 320 microplastic particles per 100 grams. Microplastics were also detected in four of the six toothpaste products formulated for children.

The findings of the study titled "Microplastics in Toothpaste: Scientific Evidence for Policy and Regulatory Action in Bangladesh," conducted by Environment and Social Development Organization (ESDO) were revealed at the organisation's office in the capital's Lalmatia on Sunday.

The study, conducted between July 2025 and June 2026, examined 34 toothpaste samples representing 19 major brands manufactured in Bangladesh, India, Thailand and Vietnam.

Among the 25 locally manufactured samples, 22 were found to contain microplastics. One of five Indian samples, one of two Thai samples and both Vietnamese samples also tested positive.

Presenting the findings, Dr Faizun Nahar, Research and Policy Associate at ESDO, said the samples were collected from retail shops, supermarkets and wholesale markets and analysed at the Laboratory of Environmental Health and Ecotoxicology of Jahangirnagar University. 

She said microplastics were detected in 76.5 percent of the tested samples, while eight samples showed no detectable level of microplastics.

According to the study, Mediplus Fluoride Gel contained the highest concentration, with 320 microplastic particles per 100 grams. Other products with relatively high concentrations included Close Up Red Hot and Closeup Menthol Fresh, each containing 160 particles per 100 grams.

The study identified Kodomo Ultra Shield Formula (Strawberry), Meril Baby (Strawberry), Meril Baby (Orange) and Pepsodent Kids Orange among the children's toothpaste products containing microplastics.