The world is covered with plastic pollution. That breaks down to become microplastics—tiny bits of plastic smaller than 5 mm. We know that it isn’t healthy to find these bits of plastic all over the planet (and in our bodies) but there isn’t much research on how this is going to affect mammals. A new study published this month in the International Journal of Molecular Science has tried to understand the long-term health impacts of this phenomenon and its findings are worrisome.