I wasn't exactly a child when I saw this commercial but I'm going to write about it anyway. I'm hoping that maybe there's someone out there who has seen it as well and needs confirmation that they didn't imagine it. From what I recall this environmental PSA played frequently because that is exactly how it got permanently lodged in my head. I'm guessing it's from around 1990 because for some reason my memories of the year the eighties ended are especially vivid.
In the commercial you see a man looking up at the camera and I think he's sitting in some kind of black void to make things even more creepy and surreal. A woman's accusing voice bellows at him, "You're the one who throws trash out of your car window" (or something like that) and the guy's face changes a little and becomes slightly more pig-like. Then the woman accuses him of something else regarding pollution (maybe dumping garbage into the ocean) and his face becomes a little more pig-like. This happens several more times until the man has a total pig face. It's possible he turns into an actual pig at the very end.
In general, I find it absurd and ignorant when folks describe bad (and particularly human) behavior by comparing people to innocent animals. I've never met a pig but quit sure they are charming animals in real life. Having said that, the Dr. Moreau-style hybrid presented in this short ad was truly hideous and disturbing. I'll never forget how the woman's voice quivered with such exaggerated contempt as she barked at the guilty-looking monstrosity. After many years, I've never seen this spot pop up on YouTube and it may very well be an only East Coast-thing. Hopefully, someday I'll meet another human who has experienced this. It was so very weird that I'm surprised that I can't find a reference to it anywhere.
And that reminds me: When I was small and living in California my across the street neighbor had a poster hanging in his garage that said, "Hell yes, I male chauvinist Pig" and it was an image of a scary man on a motorcycle with an actual pig face so maybe my aversion to pig faces has a long history. I also remember being especially taken aback by the issue of Fangoria with MOTEL HELL on the cover.