The scientists analyzed the biofilm: the plastics were covered in bacteria, including some known to make us sick. They found pathogenic bacteria responsible for causing urinary tract, skin, and stomach infections, pneumonia, and other illnesses. To make matters worse, these bacteria were also carrying a wide range of genes for antimicrobial resistance. “Plastics that you find in the water are rapidly colonized by bacteria, including pathogens,” says Vos. “And it doesn’t really matter what plastic it is.”