Thread: Food safe woods

Originally Posted by Dalboy

As far as I am aware there are lists for toxicity which usually covers things like working with the woods for example dust and it's reaction to contact with skin and also being inhaled, but not one that covers wood that comes into contact with food whether it is sealed or not.

There is no toxicity list most likely because either because no testing has been done or because the amount of wood likely to be ingested is so small that the toxicity is not important.

One of the most toxic woods in Oz is Cooktown iron wood. A few years ago I worked out that the average 80kg human would need to eat the equivalent of about 200 toothpicks in one go to be affected. For kids it would be a weight for weight case so a 10kg child would need to eat 25 tooth picks worth. For some animals like dogs the amount is much less as they are much more very sensitive to the 1080 type toxins in this wood. The amount of wood is in practice much greater that these amounts as my calculation was based on the toxicity of the young leaves and shoots which have toxin levels much greater than the wood.

This of course doesn't take into account specific sensitivities/allergies but then some people may even be allergic to something like pine, so allergy testing a large cross section of people is a very big ask.

The fact that all wood is at least slightly toxic is in fact a very useful thing as it means it has anti-biotic properties which prevents bugs growing on it and thus keeps foods from picking up external bugs. Just think about humans who used wooden utensils and food containers for millennia before metals, porcelain and plastic were available.

Originally Posted by BobL

One of the most toxic woods in Oz is Cooktown iron wood. .

Bob, what is this statement based on? The Cooktown ironwood foliage has been known to toxic to cattle based on anecdotal evidence from cattle people in this area.

Jim

Jim

Originally Posted by powderpost

Bob, what is this statement based on? The Cooktown ironwood foliage has been known to toxic to cattle based on anecdotal evidence from cattle people in this area.

CSIRO'S "Forest trees of Australia" describes the relative toxicity of the cooktown iron wood plant parts. The young leaves and and shoots are the most toxic probably developed as a defence mechanism against being eaten. In turn native Australian animals developed a resistance but cattle won't have that resistance as they have not been in Australian long enough.

Thanks Bob, I know that book well, and yes as I did mention, the foliage is toxic, but the question was about toxic woods, not foliage. Your statement states, "One of the most toxic woods in Oz is Cooktown iron wood". It is quite unlikely that Cooktown ironwood foliage would be used in a salad for human consumption???

Jim

...you could add to that the sealer or finish. As far as I can see most finishes when dry are safe for salad bowls not so perhaps not for cutting board as the cutting action would over time lift some of the timber and finish into the food, but again its very small amounts.
A good example here in Sydney I see many cutting board made from Camphor Laurel what is the most appealing is the grain and colour. They are for the most part oiled and the Camphor doesnt get into the food with any great degree. The CL is deemed mildly toxic NSW WeedWise yet it widely used with no ill effects.
So for me I dont think the choice of timber is that important other than aesthetics along with the finish. But then I turn mainly decorative pieces hollow vessels and the like.

Originally Posted by BobL

The fact that all wood is at least slightly toxic is in fact a very useful thing as it means it has anti-biotic properties which prevents bugs growing on it and thus keeps foods from picking up external bugs. Just think about humans who used wooden utensils and food containers for millennia before metals, porcelain and plastic were available.

Exactly! Bob has hit the nail squarely on the head there.

I neither claim anti-bacterial properties for the bowls I sell nor warn people that they may have small traces of toxicity. Best left unsaid in a world where there are the worried well.

As for allergic responses, it is such an individual thing that it would be impossible to construct a list of low allergen woods without one of them causing someone some grief at sometime.

I reckon we run a greater risk making things out of wood than the people who use them.

Originally Posted by powderpost

Thanks Bob, I know that book well, and yes as I did mention, the foliage is toxic, but the question was about toxic woods, not foliage. Your statement states, "One of the most toxic woods in Oz is Cooktown iron wood". It is quite unlikely that Cooktown ironwood foliage would be used in a salad for human consumption???

Jim

The most toxic part of the Cooktown iron wood is the young foliage so I looked up to concentration of the 1080 in the cooktown ironwood foliage and that's where the 200 toothpicks comes from. The wood would then require much more than 200 toothpicks to cause problems.

Thank you all for your input on this subject and the info on ironwood

I was curious and did some digging around in Google:

Toxic Woods

Why Some Woods are Better than Others in the Kitchen - CuttingBoard.com

FDA approved wood species for food contact - by PRGDesigns @ LumberJocks.com ~ woodworking community

Interesting to see Olive wood listed and yet kitchen utensils made of Olive wood have been used in Europe for millennia.

As far as Aussie timbers are concerned apart from Cooktown Ironwood foliage, I doubt anyone has undertaken proper testing of the actual timber.