Is there any research on proven negative effects? This paper is only about "potential" negative effects. From the conclusion:
Following the intake of microplastics into the human body, their fate and effects are still controversial and not well known. [...] Not enough information is available to fully understand the implications of microplastics for human health;
Following the intake of microplastics into the human body, their fate and effects are still controversial and not well known. [...] Not enough information is available to fully understand the implications of microplastics for human health;