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Food Safe Hardwoods

13K views 17 replies 7 participants last post by  MonteCristo 
#1 · (Edited by Moderator)
Sorry Lumberjocks, I forgot to add my list, so here it is

Maple
Bloodwood
Walnut
Lacewood
Purple Heart
Panga Panga
Black Cherry
Butternut
Hackberry
Olive wood
Plum wood
Rosewood
Zebra wood

Thx again Guys & Gals
 
#3 ·
I think the list of any that are not safe would be a lot shorter. Most of the supposedly unsafe ones I have heard of (eg Western Red Cedar) are about as dangerous as a baby with a wet noodle. The dust might be toxic but the wood ? Hardly.
 
#5 ·
Purrmaster - I think there are a few tropical woods (lacewood, snakewood ??) that can cause a reaction in some just by handling them, but such woods are few and far between. Also, there is a lot of buzz out there about food safe finishes. I think it is Bob Flexor who says any fully cured finish is basically food safe, and he should know.

But saying "it's food safe" helps boost sales I guess . . .
 
#6 ·
From what I gather reading a bunch on this site is that there are potentially a few issues, and they depend on application. What follows is in reference to making a cutting board.

Some say not to use nut type trees (think something like walnut) because of possible allergic reactions.

Some say not to use oak because of the large pores and potential for bacteria to get in to them.

I can't comment on the accuracy of either of these, since I have not made a cutting board.
 
#7 ·
Monte Cristo,

I still have a problem with a general statement like: "I think it is Bob Flexor who says any fully cured finish is basically food safe, and he should know."

Lead based paints are toxic no matter how old they are and at one time they did come in clear. Then there are some of the alkyd Enamels… highly toxic if ingested after curing. (My father in law lost a lung and half of his kidney functions from refinishing a type of Alkyd enamel when working at a hospital as maintenance).
 
#9 · (Edited by Moderator)
Dallas There is a massive difference between toxicity while working a finish (applying it, sanding it . . .) and its properties after it has fully cured. Viz-a-viz lead, I am pretty sure lead was banned in paint quite a while ago. Also, I wasn't thinking of paint as a finish for a food use item; it seems obvious that one would not want to use paint as a finish for food related use as for the man-made paint to be tough enough to wash etc, it very likely would have to have some nasty stuff in it.

But yes, some finishes are less friendly than others and, if a guy wants to be super safe or knows that the user may be more sensitive than most, stick to tung oil or similar. But Bob Flexnor oughtta know. He's a huge name in the finishing world and the author of a number of well respected books. I'll take his word before a lot of self-proclaimed experts.
 
#10 ·
You are correct about Flexner. He says (and his arguments are convincing) that all finishes are safe for food once fully cured.

But I don't necessarily agree with him about cutting boards. When you are chopping things on a cutting board you are going to be chopping off bits of the finish as well. So I would think you'd be ingesting the finish as well.

However, once a finish is totally dried and cured there isn't much actual matter on the wood, even on a film finish. So even if you do end up gobbling up some lacquer the amounts may be so miniscule as to be harmless.

With that being said, I'd be fine with using just about any finish on something like a salad bowl or a tray. But on something where sharp knives are going to be used all the time I'm going to stick with mineral oil and wax. Your mileage may vary.

You're quite correct about woods from nut trees. I had totally forgotten that. For what it's worth I'm allergic to all tree nuts and have fiddled around with walnut wood and have encountered no problems. Same with tung oil (which is oil from a nut), no problem here. Yes, it was 100% tung oil, not a "tung oil finish."

I've also heard the same thing about oak and it makes sense to me. The large pores could be places for nastiness to get trapped. I've read maple is ideal for cutting boards and I'm making an end grain maple cutting board now.

Lead was banned in the 70s so you only have to worry about it with very old coatings.

As trivia, according to Wikipedia the actual tung nut from the tung tree is quite toxic. If you eat a few tung nuts you're probably going to die. I can't speak for the oil itself. I haven't drunk any tung oil down to find out. I haven't read anywhere that tung oil is toxic, even to ingest. Not that I would recommend taking a few swigs of tung oil.
 
#11 ·
Dwight,

Making such a blanket statement as "ALL finishes are food safe after curing" could lead one, especially newbies, to believe that they can put any finish they want on any surface that is used for food.

I've seen cutesie cutting boards in peoples kitchens made from pine or fir or hemlock that had a clear coat of varnish and under that was painted a flower or something bright.

Lead was only banned in the US in the 1970's. It was not banned worldwide.
Lately it has been found that many foreign companies that supply finish to the US have trace amounts or more of lead because the machinery isn't cleaned between runs.

Would you consider using a non-food safe finish on a baby crib? Lot's of people paint them with whatever the kid can gnaw on.
The CPSC has stopped imports of a lot of baby furnishings because the country of origin used lead conraining clear finish.

Even your buddy Flexner admits that lead containing varnish was available in the US until the 1970's.
 
#12 ·
This topic comes up a lot. I would really like to see some scientific proof of a wood species not being food safe. There are known allergies to certain species, but the warnings are people working with them; not for finished products.

In fact the species of wood most recommend for cutting boards is considered quite toxic and more so than most exotics. Read the warnings below about hard maple:
Hard Maple, along with other maples in the Acer genus have been reported to cause skin irritation, runny nose, and asthma-like respiratory effects.

As far as finish, I am with Dallas on this one. I stick to mineral oil and beeswax. In theory all finishes cure food safe, but mineral oil and beeswax do the job just fine.
 
#13 ·
I think the definition of "food safe" is going to depend on what you have left once the finish/paint has fully cured. My guess is that if I slapped lacquer on a cutting board and allowed it to fully dry, the amount of actual "stuff" on the board will be quite small. Such a small amount that munching on it wouldn't be harmful.

On the other hand, I don't think I'd be fully comfortable munching on lacquer. Or poly. Or varnish. For cutting boards I'll stick with mineral oil.

Besides, I'd think that on a cutting board you'd wear off the finish awfully fast with knives cutting into it all the time. Seems easier just to use mineral oil.

Dallas: You make an excellent point about the possibility of lead in coatings that come from overseas. I think it's fairly rare that this happens but I too have read that it does happen. I believe there were concerns some years ago that some imported toys had been painted with paint that had lead levels way above the allowed maximum.

If I was painting a baby crib I would probably see if I could get the paint tested for lead levels before using it. It doesn't take much of a nasty chemical, especially lead, to have to harmful effects on a baby. And as you pointed out, babies chew on everything.
 
#14 ·
In 2007 I had to dump off some of my (then 1 year old) son's Thomas the Tank Engine toys back at Toys R Us. They were suspected to contain lead paint. That wasn't too long ago.

Supposedly the issue with finishes isn't necessarily the solids, but whatever solvents they contain. After a length of time, the solvents flash off and you have your "food safe" finish. I'm with you purrmaster. Finish, no matter what it is will get ruined in a hurry on a cutting board. Mineral oil is easy, and easy to reapply.
 
#15 ·
Dallas:

My guess is a whole lot more kids die from choking on toys containing lead than do of lead in the toy or crib paint. Yes, some newbies will be dumb enough to not read guys like Flexnor carefully. But, if they are that stupid, they will likely suffer even more so doing some other stupid thing. There's no law against being stupid. They probably don't dispose of antifreeze carefully either. Should we ban that ?

Flexnor is not my buddy, but odds are he knows a Hell of a lot more about finishing than you or I.
 
#16 ·
lumberjoe:

That is my understanding as well. The solvents are the toxic part. Once all the solvents have evaporated you are left with a film that is basically inert. I'm reading Flexner's second book "Flexner on finishing" now. He claims that even if you did end up swallowing a chunk of cured finish it wouldn't harm you. I'm not sure I entirely buy that. I know I'd prefer not to eat a chunk of varnish. Which is what you would get, I would think, if you use it on a cutting board.

If I was going to a baby crib or a toy for a child I would use either paint that is truly lead free or shellac. I'd probably go with shellac. You could gobble down a bunch of shellac flakes and you'd be fine.
 
#17 ·
Interesting research.
I've looked at at least a dozen MSDS sheets for Boiled Linseed oil, (Which is a clear finish and is the base for many oil based paints.
The MSDS sheets vary all over the spectrum from containing almost zero information on toxicity to being a known carcinogen for animals but not tested on humans to containing cobalt driers, (which by the way stay in the dried finish and are highly toxic), to containing manganese salts which may or may not be hazardous.

I've never paid a lot of attention to more than one or two MSDS sheets on a particular compound before, but all these entries seem to point to the fact that an MSDS sheet isn't much good because it is written by the mfg, not by any real scientific method.

Just for instance, I found the MSDS sheet for Klean-Strip BLO from Rockler and at least 5 other companies… all of them were vastly different.

I still believe that keeping an open mind on toxicity is more important than relying on the word of a single individual who may or may not have any background in finish toxicity.

To make a blanket statement that all finishes are non-toxic once dried could lead to some real problems.

Generalities are just that…. generalities and can come back to bite you in the arse.

All of you are free to believe what you wish, as I mentioned to one fellow who finished his food prep project with BLO….. it's your project, not mine, make it the way you see fit.
 
#18 ·
This time I agree with Dallas ! But I would also remind guys of the health food nut who, while jay-walking back to his car, got run over by a Coke struck. The odds are incredibly higher of dying of something else. And that baby that chews on furniture ? Better not do that with Big Box Store stuff. MDF isn't just hard as Hell on tools.
 
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