Microplastics in the commercially available branded milk in Bangladesh: An emerging threat for human health

Abstract

Microplastics (MPs) are polymer-based particles commonly found in diverse foods that pose serious human health impacts throughout the food chain. Assessment of MPs in different food products is a prime measure to combat MP-related food contamination. Therefore, this study first investigated the identification, characterization, and potential risks of MPs in the commercially available milk brands (19 dry powders and 06 liquid brands) in Bangladesh. The presence of MPs in milk samples was 279.47 ± 134.26 particles/kg and 182.27 ± 55.13 particles/L for powder and liquid milk, respectively, with a significant variety. Study findings displayed miscellaneous colors, fiber shapes (powder=78 %; liquid=81 %), > 0.1 mm sizes (powder=69 %; liquid=65 %), and polyethylene (powder=48 %; liquid=44 %) dominating MPs categories. The pollution load index indicated significant pollution due to the high abundance of MPs. Further, other risk-evaluating indices including contamination factor and Nemerow pollution index represent moderate to high MP-induced pollution for both milk samples. Low to moderate polymeric risks are exhibited by powder and liquid milk samples. Children could be exposed to 3.43 times higher MPs than adults through daily oral ingestion, which has significant health effects. This study found that powder milk was the most severely MPs induced risk than liquid milk. Consequently, this study finding established a reference point for MP contamination in milk, so special attention must be taken during production, storage, and packaging stages to reduce MP contamination.

Keywords: Bangladesh; Commercial milk; Dietary exposure; Microplastics; Pollution indices.