The United Recyclers Group, a trade organization for auto recyclers — or as we gearheads lovingly call them, junkyards — says the Cash for Clunkers bills (there are a couple versions) now before Congress would hurt them and those of us who depend on them for organ transplants for our old cars. Their interpretation of the proposed law says it will put an end to selling engines and transmissions from junked cars.

It would probably result in cleaner air, as newer cars generally spew a lot less pollution per mile than older cars. And it would also probably result in the sale of more new cars, at least part of the agenda.

But it will also have a big effect on Tucson and Arizona streets, moreso than almost anywhere else.

Because of the low humidity — and warm winters, which mean no snow and therefore no corrosive road salt — we’ve got a lot more old cars than nearly anywhere else in the U.S. They just don’t rust out here.

If passed as proposed, the law would nix the sale of engines and transmissions from wrecks and transplanting them in old cars, such as the 1970s and 1980s-era Volvo 240s — easily mistaken for overturned refrigerators with wheels — putting around Tucson’s streets.

I’ve had out-of-town gearhead visitors positively snort and sputter about the Tucson version of the Antiques Roadshow we have on our streets every day. They think they’ve been time traveling. You just don’t see as many old cars any place, well, other than maybe Havana.

The “Antiques Road Show” is an every day event in Tucson. I recently counted five 1960s-era air-cooled Volkswagens in a half-hour while driving around Midtown: three Beetles and two VW Buses — one a rare 21-window model. Dude.

And, worst of all, the proposed law could put an end to Slug Bug, that pre-teen family driving game in which the adolescent passenger who first spots a VW Beetle yells “Slug Bug yellow” or “Slug Bug blue” and gets to punch his or her sibling in the upper arm, to the never-ending joy of the teeth-grinding adult chauffeuring them. Yeah. On second thought, clean air is important and we all have to make sacrifices.