If it's treated lumber it should have kind of a green tint to it. Most treated lumber it also noticably heavier than untreated wood. I would not go so far as to call it a TOXIC bed even if it was made with new treated lumber. (Toxic meaning all the veggies will be poisonous) Lining it with plastic is what I would do if you are worried about arsenic or other chemicals getting into the soil. I wouldn't tear the whole thing down just because it was made with treated lumber. Especially old, used treated lumber that has had probably years of exposure. I beleve I read somewhere that even certified organic gardens can use treated wood that was already in place before a certain date as a grandfather clause. A barrior between the soil and the boards wouldn't hurt though and would be pretty easy to do. Good luck with your new garden.

It might have other stuff on it, even if its not treated. I've heard of using kerosene on cement molds to help them not to stick. Just another possibility.

So how big are they? Got any pictures? Don't leave us hanging here...

Thanks for the info Bob!!! My biggest concern was more for my 3 year old daughter ingesting any second hand chemicals from tainted produce.

I have several beds but the one I am most excited about is a
35' long x 24" x 18" tall!
This is one long SINGLE row just for heirloom tomatoes. FULL sun exposure from sun up to sun down.
the others are jusr generic 4 x 6 beds for veggies.

I wouldn't worry too much about tainted produce especially if you line with plastic. Most, if not all soil has trace amounts of arsenic, among other things, in it naturally. One of the things that prompted the discontinued production of treated lumber containing arsenic was the danger of the dust produced when building things with it and using it as play ground equipment where small chidren might tend to put there mouths on the wood or cut/scrtch themselves on the wood. The newer produced treated lumber allegedly does not contain arsenic. But it probably contains alot of other nasty things to preserve wood. I would not be suprized to see red flags out on the new stuff in the future. The best alternative I have seen is the railroad ties that are made from re-cycled plastic. They need to come way down in price though to make them affordable for the home gardener.

There is a great deal of information regarding this concern on the web. I'll attach one good link that you should read all the way through. You may have some second thoughts about what to do afterwards.

What did you mean 'line with plastic'? The wood?

Here is a link that might be useful: Good information....YOU decide

Thanks rhizo, that was a very good artical.

Myself, I would go ahead and use the raised bed. However, if you are worried you will probably always worry about it every time you eat anything. Might just be better to rebuild, if you can't clear you mind. I really do not think there is a danger.