Are we eating microplastics with our staple food? A pioneering study of microplastic contamination in store-bought rice and cooked rice in Bangladesh

Microplastics (MPs) pollution in food is becoming a rising concern around the world. In Bangladesh, previous studies found MPs in various food items including sugar, tea, salt, and fish. However, research on MPs contamination in Bangladesh is still missing. Therefore, for the first time, this study investigated the abundance, distribution and chemical composition of MPs in rice of Bangladesh. Rice was assessed in raw and traditionally cooked form to estimate potential human exposure of MPs via rice in Bangladesh. 15 commonly consumed store-bought rice samples were analyzed for MPs contamination. Physical and chemical characteristics of MP's were detected using a stereomicroscope, and Fourier-transform infrared (FTIR) spectroscopy. MPs were detected in all samples, in raw rice the microplastic content was 67.20 ± 24.21 items/g and 32.47 ± 12.46 items/g in the cooked rice samples. Fragment shape, black and blue colour, and < 0.1 mm were the most prevalent characteristics observed. Nylon, nitrile, acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), and multiple other polymers were detected in both types of samples. This study found that traditional cooking process in Bangladesh can significantly reduce MPs from rice. But the presence of MPs in rice is high comparing to other countries. According to per capita rice consumption, an adult Bangladeshi intake approximately 15,226.87 ± 5843.59 items of MPs daily via rice. This finding of potential human exposure of MPs thorough rice intake in Bangladesh provides foundation for further research on health impacts associated with MPS and mitigation strategies.