Food safe finishes

[Dan Larson]

No hard feelings at all, but it doesn't seem like very good general advise for those of us willing to accept reasonable risks in order to use more tractable finishes.

Absolutely yes, I agree with you on this point Steve. That is why I felt like I owed you guys a better explaination of my first post.

Dan

[Dan Larson]

One additional question from a toxicological perspective. Aren't exposures to heavy metals somewhat cumulative? As in they tend to stay in the body in places like the liver for long periods of time?

Doug, you've zeroed in on an important, and controversal aspect of toxicological profiling-- acute (short term) versus chronic (long term) exposure. Typically toxicological evaluations are acute studies with very high exposures. We then try to extrapolate the risk of chronic exposure at a more realistic dose level based on the findings from the acute studies. Often this approach is valid, yet sometimes it's not. As scientists we defintely prefer to do more chronic studies, but there is a practical limit to how much time we can take to do these things. In the case of high value chemicals, like pharmaceuticals, we can afford to study them very, very extensively before putting them out on the market. In the case of bulk chemicals, this is not always true.

To broadly generalize, yes the effects of exposure to heavy metals tend to be cumulative. Our nation had to deal with this one once we figured out that our daily, yet relatively small exposure to lead from the gasoline that we were burning was slowly poisoning us.

[Steve Schoene]

We are not sure of a great many things. We are absolutely sure of a great many risks that we choose to accept on a daily basis. Taking a shower is one such risk.

Can anyone cite even one documented example of illness caused by (non-lead) metallic driers in clear finishes? (Industrial exposure is another matter entirely, with a potential for more concentrated exposure, and exposure in forms that are more risky such as fumes that may be breathed. And clearly, dumping cobalt into the enviroment should be avoided.) The absence of consumer injury suggests that the magnitude of risk is dramatically less than many of the risks we take daily. Personally, I don't believe the risk being avoided is sufficient to be worth giving up the benefits of BLO for popping grain, for Rockhard varnish on table tops, or for oil based stains and fillers. It seems very alarmist to be warning people away from drier risks while not warning them from getting in the car to do something "frivolous" like seeing a movie, or eating dinner out--activities almost certain to have greater risk of injury than from ingesting crosslinked metal driers from clear finishes.

T&T finishes for example, while liked by some knowledgable people, are also causes for anquish for others who report failure to cure for weeks. That's a risk I don't want to take. I love shellac, but a great many argue for more durable finishes. Mineral oil does just about nothing except giving a bit of color.

[Jim Becker]

T&T finishes for example, while liked by some knowledgable people, are also causes for anquish for others who report failure to cure for weeks.

I have only heard this (and experienced this) relative to the Varnish Oil...the other two formulas (oil and oil/beeswax) have never failed to cure for me. I'd never buy or use the Varnish Oil formula again! (Fortunately, it was the smallest container)

[Steve Schoene]

Thanks Jim for clarifying that about the T&T finishes. I had avoided the whole brand since I had not focused on the varnish oil as the only problem item.

[Jim Becker]

Steve, I especially like the oil/beeswax version for decorative objects. Both it and the oil-only version are VERY thick in the can due to the polymerization process used to avoid the driers and I usually warm them to about 135 degrees in a water bath. (I've done the same with regular BLO, but usually don't in that case for expediency) I get a really silky finish with the stuff...wonderful to the touch.

Acutally, I'll be honest...Dr. SWMBO's cherry desk is finished in the T&T oil/wax formula and has stood the test of nearly 7 years of, umm...abuse. It's been waxed two or three times in that time period, the last time being in late 1999 after we moved to this property. Looks great!

[Tom Spallone]

So, I could use water based poly on my projects and be able to sell them commercially with no repercussion from the FDA?

[Tom Spallone]

So, I could use water based poly on my projects and be able to sell them commercially with no repercussion from the FDA?

[Steve Schoene]

Thats what I believe. There should be a mention on the MSDS if there were an issue.

[nic obie]

Another option is to use nothing at all on your cutting boards. Unless they are just for decoration the finish only gets in the way of the woods natural tendencies to kill harmful bacteria.

The boards will pick up enough oils from the food sliced soon enough anyway.