For a good idea about about what DuPont’s PFOA has done, check out this article from the NYT:

The Lawyer Who Became DuPont’s Worst Nightmare

Three short paragraphs from the article...

At one point, the video cuts to a skinny red cow standing in hay. Patches of its hair are missing, and its back is humped — a result, Wilbur speculates, of a kidney malfunction. Another blast of static is followed by a close-up of a dead black calf lying in the snow, its eye a brilliant, chemical blue. ‘‘One hundred fifty-three of these animals I’ve lost on this farm,’’ Wilbur says later in the video. ‘‘Every veterinarian that I’ve called in Parkersburg, they will not return my phone calls or they don’t want to get involved. Since they don’t want to get involved, I’ll have to dissect this thing myself. ... I’m going to start at this head.’’

The video cuts to a calf’s bisected head. Close-ups follow of the calf’s blackened teeth (‘‘They say that’s due to high concentrations of fluoride in the water that they drink’’), its liver, heart, stomachs, kidneys and gall bladder. Each organ is sliced open, and Wilbur points out unusual discolorations — some dark, some green — and textures. ‘‘I don’t even like the looks of them,’’ he says. ‘‘It don’t look like anything I’ve been into before.’’

Bilott watched the video and looked at photographs for several hours. He saw cows with stringy tails, malformed hooves, giant lesions protruding from their hides and red, receded eyes; cows suffering constant diarrhea, slobbering white slime the consistency of toothpaste, staggering bowlegged like drunks. Tennant always zoomed in on his cows’ eyes. ‘‘This cow’s done a lot of suffering,’’ he would say, as a blinking eye filled the screen.