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Should finishes with added driers be avoided due to their toxicity?

I understand today's driers are not as toxic as those used years ago, but even these new cobalt driers are still not food-safe. Well, what about on a guitar neck, where your sweaty hand is in constant contact? Will the sweat cause the driers to leech into the skin or are the driers rendered inert after the finish has dried?

Sorry if this is a dumb question - just a little concerned after reading Tru Oil has driers in it and I know many people like the feel of Tru Oil on a neck.

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Ken Cierp

http://www.kennethmichaelguitars.com/

"The product can cause allergic skin reactions (e.g., rashes, welts, dermatitis) upon prolonged or repeated exposure".

Thanks, I should have looked there first. I suppose ALL "boiled" finishes should be avoided entirely if there is direct and prolonged skin exposure.

The "prolonged exposure" might be to the finish in the liquid state. I've never known anyone to be affected by skin contact with a dried finish (but I suppose it's possible).

Yeah, I'm think I'm opening up a whole can of worms here. Confusion when I google further what makes something food safe. Some say any finish is fine once the solvents gas off, but others say the metallic salts (toxic) are left behind. So, even if it's not food safe, is there still any risk of exposure over time when using a neck finished with driers - Boiled Linseed Oil, Polymerized Tung Oil, etc.? Oh man, maybe I should have this thread deleted.

The drier compounds would be locked up into the cured finish. I don't think this is an issue. By the way, my day job involved assessing the risk of exposure to environmental contaminants. Dermal exposure normally involves liquids, residues or pure compounds, which is not the case here.

Maybe, maybe, if I were the nervous sort and prone to chewing on the neck, as one might a pencil, and I did this repeatedly for years on end until the finish was completely worn away and ingested, there might be some slight reason for concern. But the computer monitor I'm sitting in front of right now would probably kill me before then, so I'm going with Barry and Clay on this one.

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George :-)

The amount of heavy metal catalyst in most finishes is generally pretty microscopic. The siccatives and dryers help the oil to harden - it's not a significant component of the finish.

Your best bet is to evaluate an MSDS for a specific product. Its difficult to make sweeping statements. That said and all..... I will make some sweeping statements.

How do you get nasties into you? Eating it and breathing it. Except for the case of some very specific solvents and pesticides - chemicals don't generally absorb through the skin.... Skin is a fantastic barrier...

The worry about breathing is generally solvent fumes - not dryers... These chemicals are metal salts and don't evaporate into the air.. That leaves eating it. Which brings us to:

Food safe generally comes along with intentional, prolonged food contact and the high likelihood that you will be eating some of it. Not likely with guitars.... You don't store or prepare raw food inside or on your guitar.....

Child toy safe makes an assumption that kids may chew on or unintentionally eat parts of it.... Perhaps it might be a concern with a plastic toy ukulele you guve a toddler. But - that's not likely with these guitars.

So... For players... Not many players have skin or sweat that's reactive enough to dissolve cured poly or oil varnish. Shellac - maybe... But that stuff has no dryers in it.... Shellac is used as an edible coating on many things. At worst - a player may be able to wear through 0.005" of neck coating thickness over 10 or 20 years. That's perhaps 1 gram of finish in 10 years - with a heavy metal content of 0.00005% or less.... Decimal trash exposure.

That leaves the greatest risk for the luthier finishing the instrument... As we went through - most of this stuff has to be eaten for your exposure... Which boils down to:

Don't be nasty... Wash your hands like your mother told you!!!!! Working clean and having good hygiene is your #1 defense.... Washing before you eat/smoke/chew/drink and NOT leaving your food/drinks/tobacco in your finishing area is your #1 protection. And it's a very effective protection in real life.

Used to do a lot of gunstocks with TruOil. The prevailing method was to work slowly and just rub it in with our fingers. Worked great and so far my fingers have not fallen off. I don't think there is a significant risk, at least with TruOil, assuming they have not reformulated it.

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Steve Smith
"Music is what feelings sound like"

Thanks for taking the time to reply, guys. I think you're right, the driers are locked up in the finish once cured. Skin is, indeed, a fantastic barrier, but it's the paranoid part of me that pictures Jimi putting the LSD in his headband and letting the sweat do its work. Probably an urban legend, but I was totally seeing my sweaty palms doing the same thing to the driers in a neck. Glad to know that will not happen. Tru Oil is banned here (Proposition 65), gonna try a BLO finish on the next neck if that hasn't been banned, too.

I don't know if this helps, but Tru Oil is not banned in California. Tru Oil contains VOCs. Because of the terrible smog issues in the Eastern part of Los Angeles where light industry is concentrated, CARB now requires that manufacturers of finishes test their products to determine how much VOC's they release. Apparently the owner of Birchwood Casey (the manufacturers of Tru Oil) refused to have the product tested. I have heard alternately that they did so for economic and/or political reasons. Either way, without the required testing the product is not allowed to be sold in California.

So it isn't cancer that keeps Tru Oil from being sold. I still wear gloves and am not inclined to drink the stuff.

The thing to do is find the specific products sold in your market.... For example - head on over to the local Woodcraft store, Ace hardware, or Marine/Sailboat store and see what they sell...

Ace interior gloss varnish is used by several prominent luthiers, as are several different sailboat varnishes, and a couple hardwood floor varnish products...

Barring that - make a road trip to Arizona for some bootleg Tru-oil... You are a hobby person - the rules are very different in how they apply to a business vs the general public not doing business... For example - you the general public person at large can throw a light bulb in the trash without SWAT raiding your house... The business around the corner has to do all sorts of paperwork and hire special disposal companies to get rid of their lightbulbs..

Ace interior gloss varnish is used by several prominent luthiers

Which ones I'd like to contact them?

Thanks

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Ken Cierp

http://www.kennethmichaelguitars.com/