Hidden Sources

Microplastics do not all come from bottles and bags breaking apart. Two of the biggest sources are surprisingly ordinary. Synthetic clothing sheds hundreds of thousands of fibers in a single wash, which flow straight through treatment plants into rivers and the sea. Car tires shed tiny particles onto roads, and rain washes that dust into waterways.

The particles also act like sponges. They absorb toxic chemicals from the water, so an animal that swallows them takes in the plastic and the poisons stuck to it at the same time.