Images of starving polar bears staggering across the snow earned the species the dubious honor of being the “poster child” of climate change. But now another human-caused environmental danger threatens these apex predators: pollution from a class of 12,000 chemicals known as per- and polyfluoroalkyl substances (PFAS). And they’re not the only ones. The nonprofit Environmental Working Group analyzed hundreds of recent peer-reviewed scientific studies and found more than 120 different PFAS compounds in wildlife. Some 330 species were affected, spanning nearly every continent — and that’s just some of what scientists have identified so far.