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Re: Pressure Treated



Dear Stacy Charland,

    Many years ago I did some investigation on pressure treated lumber and I think I
can remember a few things. One of my friends owned the largest treating company on
the Texas Coast and we discussed this issue a lot. The Texas Agricultural Extension
Service also has some input, in favor of treated wood.

    Most pressure treated wood is treated with a product called Wolman made by Dow
Chemical, hence Wolmanized wood. The active ingredients are copper, chromium and
arsenate, CCA. The wood is actually soaked in the material, I'm not sure whether or
not there is any pressure applied. The active ingredients do inhibit fungal and
bacterial degradation. There is some leaching of the CCA into the surrounding
environment, but most of it does remain with the wood. A cotton wipe test will
usually have traces of arsenic, regardless of the age of the treated wood. Dow has
done extensive research into this issue and has some publications on the subject.
Dow says there is no significant detrimental environmental effect from treated
lumber. Most recently they have tested CCA leaching into the marine environment, but
I have not read the results. I highly recommend you ask for their literature on the
subject.

    I stopped using treated lumber about a decade ago, mainly due to the long term
effects of repeated exposure to arsenic, especially on young children. I have also
read that there is a presence of CCA in  human semen in 80% of the world's male
population. I can not remember the reference, but that is an astounding number if
true. Conversely, CCA really prolongs the usable period of wood, up to 50 years, and
can greatly decrease deforestation caused by the harvesting of wood products.

    Alternative materials for fence posts are: metal, recycled plastic lumber and
juniper (called cedar) where readily available. Treated lumber is a double edged
sword; it prolongs the life of wood, decreasing pressure on shrinking resources, but
it is treated with a toxic cocktail, that is why it works. I do not think that the
presence of treated lumber would be an impediment to organic certification.  I am
drawing on misty memories to write this and am prepared to be wrong. There are other
post materials available, the question is are they available and affordable.

Kevin, doin' the sweet pea frug.


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