 When microbeads are washed down the drain, they subsequently pass unfiltered through sewage treatment plants and make their way into rivers and canals, resulting in plastic particle water pollution.A team of researchers from Uppsala University published and subsequently retracted a study (at least one researcher was found to have fabricated results)  which stated that one of the various animals affected by microbeads was perch, a freshwater fish.The beads can absorb and concentrate pollutants like pesticides and polycyclic hydrocarbons.