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Chromate Conversion Hazard?

Is the chromate conversion (Alodine/alocrom) FINISH of al.alloy, (not the application process), at all hazardous if not painted?

David Wibrow
- Gloucester, UK
2001

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That's an excellent question to which I've never seen an authoritative response, only conjecture. So I'll add my conjecture!

There are some problems that are too complex to solve. If you snip a maple leaf off a high branch of a tree on a still day, all of the world's computers can't tell you whether it will land North, South, East, or West of where it hung, because of the unfathomable complexity of the aerodynamics.

Hexavalent chromium is considered carcinogenic in the U.S.A.; but the relationship between cancer and even fairly severe industrial exposure to hexavalent chromium seems limited and difficult to prove or disprove. So I suspect that to demonstrate that very occasional skin exposure to a dried gel of hexavalent chromium a few millionths of an inch thick is carcinogenic would probably take an astronomical, utterly impractical sample size and control sample size, such that maybe there simply is no current authoritative answer no matter how hard we look.

But if anybody has accumulated any data on this, or is an epidemiologist or epistemologist we'd love it if they'd chime in.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2001