Microplastics (MP) were recognized as an emergent pollution problem due to their ubiquitous nature and bioaccumulative potential. Those present in salt for consumption could represent a human exposure route through dietary uptake. The current study, conducted in Bangladesh, reports microplastics contamination in coarse salt prepared for human consumption. Sea salt samples were collected from eight representative salt pans located in the country's largest salt farming area, in the Maheshkhali Channel, along the Bay of Bengal. Microplastics were detected in all samples, with mean concentrations ranging from 78 ± 9.33 to 137 ± 21.70 particles kg-1, mostly white and ranging in size from 500-1000 µm. The prevalent types were: fragments (48%) > films (22%) > fibers (15%) > granules and lines (both 9%). Fourier transform mid-IR and near-IR spectra (FT-MIR-NIR) analysis registered terephthalate (48%), polypropylene (20%), polyethylene (17%), and polystyrene (15%) in all samples. These results contribute to the MP's pollution knowledge in sea salts to understand and reduce this significant human exposure route and environmental pollution source in the future.
Research on microplastics must be harmonized. Therefore, we thoroughly evaluated in the Association of Southeast Asian Nations (ASEAN) region, addressing challenges and priorities in protocol harmonization and microplastics research promotion. Of the 615 papers searched by the Web of Science, 164 were used for this systematic review. The number of ASEAN research articles has increased over time. Examination of research protocols in various sampling environments revealed several challenges: 1) Disparities in access to sampling locations affect the research extent; 2) Outdated protocols and limited access to technologies such as FTIR (Fourier-transform infrared) spectroscopy result in less harmonized and potentially lower-quality data; and 3) Insufficiently detailed methods and QA/QC information hampers comparability. We offer procedure updates to overcome these limitations and cover environmental microplastic study gaps. Other countries in the Global South may encounter similar challenges, making this review a valuable contribution to advancing global microplastics research and fostering international collaboration.