Lack of Evidence for Microplastic Contamination from Water-Soluble Detergent Capsules

Abstract

This study investigates the ability of water-soluble detergent capsules to effectively release microplastics from their composition. A total of 39 different brands of water-soluble capsulated detergents were tested, 20 of them for washing machines and 19 for dishwashers, from four different countries in the EU, i.e., Spain, Portugal, Belgium, and Italy, as well as two different devices for microplastic recovery from laundry wastewater. Wastewater samples from all laundry capsules reported microplastics, mainly as entangled fibers from PET blankets, although none could be associated to capsule itself. This paper displays, through a calculated rate for microplastics, that fiber shedding from clothing maybe related to different detergent characteristics. Wastewater from both catching devices reported microplastics after their use, although samples from Guppyfriend bag displayed less fibers than those collected after the use of Cora Ball. Eventually, wastewater samples form dishwashing detergent capsules were much less contaminated with microplastics than those from laundry ones.