[inishindie]

Hi

I have just received this question. Has anyone had experience in such matters as I am not sure if pressure treated wood leaches.....

"I have just planted flowers and two miniature apple trees in raised beds in my garden. I had heard that old railway sleepers were banned so I bought smaller pressure treated timber sections instead. I want to maintain the garden organically but now I'm worried that the timber will contaminate the soil. I hope to yield apples for consumtion and grow herbs that I can use for pest control.

Do you think there is any risk to our health using this timber?"


Cheers

Ian

[walltoall]

Until 2003, the preservative most commonly used in residential pressure-treated timber worldwide was Chromated Copper Arsenate which is 'toxic'. If it wasn't it would not fight off the fungi, bacteria, insects, gnawing animals that want your post for breakfast dinner and tea. There's no comparison whatever between toxicity of the chemical and the toxicity of the wood so preserved. Common table salt is toxic in case you did not know. So is vinegar. Extensive studies and research on CCA brought mixed results, because there were vested interests at work on all sides. Fear of litigation even if it was failed litagation caused the timber industry to stop using CCA in2003. You'll more likely have other exotic copper compounds in timbers used for houses and gardens. There's no hard evidence and never was that any of the chemicals mentioned ever 'leached'. The amount of toxin in a fence post is pretty small and most of it is well into the timber. 'Arsenate' is still being used in certain very hostile marine and industrial environments as it remains the most effective best preservative available since creosote was outlawed. However, anyone on this site who feels they need belt'n'braces insurance could paint the surface of pressure treated timber going into the ground with an oil such as boiled linseed.

All the fore-going is an opinion by the way. If you suck lollies from this site I am not responsible for the state of your teeth. Read the small print. OK?

[inishindie]

Thanks walltoall, that's a very informative answer.

I did notice on an earlier forum piece -
http://www.gardenplansireland.com/forum/about1161-15.html

that a strip of polythene was put between the soil and the wood (although some would say the plastic would contaminate the soil too)

I have passed the information on for them to make an informed decision..

Thanks again

Ian