Tiny particles of plastic are in our food, water and even the air we breathe. There is insufficient evidence to establish the impact of microplastics on human health. But the absence of evidence doesn't mean they are harmless.
Two communities — one in Canada, one in the U.S. — share both a border along the St. Marys River and a toxic legacy that has contributed to high rates of cancer. Now the towns are banding together to fight a ferrochrome plant.