Subject: Is CCA PT lumber OK for a [Pressure Treated Lumber faq1 - gen. info]

From: [email-masked] (Jim Mcnelly)
Date: Sat, 9 Apr 94 13:06:00 +0600

Doug Caprette asks:

D>Hmm, I get the impression that I may have just missed a discussion on this
 >topic.

D>Anyway, can anyone provide some informed opinion as to whether there would be
 >any problems anticipated with the use of Chromated copper arsenate treated
 >lumber for a grape arbor?

D>"I think that this task is appointed for you, Frodo;" -- Elrond

Great tagline Doug,

Here is my FAQ on Arsenic Lumber, and in another post, the product
safety sheet that is *supposed* to be handed out to every purchaser of
the product which was a part of the EPA agreement to allow the product
to be sold.

Additional information on CCA, Chromated Copper Arsenate.

The wood has been tested by the Minnesota Pollution Control Agency,
Hazardous Waste section to be over 3000 parts per million arsenic. The
EPA limit on arsenic in sewage sludge for unrestricted use is 11 PPM.
There is at least one case of 24 cows dying from eating ash from CCA
wood ash in MN and several cases in other states. There is another case
of arsenic poisoning in a Wisconsin family from a backdraft in their
fireplace while burning treated wood.

Arsenic is associated with hair loss, diarrhea, asthma, skin cancer and
other skin disorders. Particular caution should be exercised if the wood
has a white, gritty residue on the surface, as these may be arsenic
crystals. Penetrating oil stain may slow down weathering of fibers and
reduce arsenic surface residues. The exposed ends of boards are more
likely to leach arsenic than the rest of the board. The wood should be
resealed every two years.

Of particular concern is sawdust left at construction sites that can he
ingested by children, pets, or become exposed to the skin. Runoff of
sawdust into ponds, pools, wells and gardens is another concern. Arsenic
is rated by the EPA as a class A carcinogen, the top level of risk.
Children "mouthing" the wood are also at risk, especially the board ends
that release twelve times the arsenic of the rest of the wood. This is
especially a concern as arsenic treated wood is a common component in
playground equipment. Tests for arsenic beneath children's play
equipment have run as high as hundreds of times above background levels.

Treated wood is also a problem in disposal. While such a broad range
biocide such as CCA retards decay, it does not stop it. Estimates of rot
resistance of 20 to 50 years are common. The wood will *eventually*
decay, and with the sawdust and ends from construction, will have to go
somewhere. The treated wood industries have lobbied to have CCA treated
wood exempted from hazardous waste designation through a de-listing
procedure that is still unclear. The product is currently allowed to be
sent to conventional and demolition landfills.

It is often burned with other wood wastes and is commonly chipped into
landscape mulch or compressed into toxic fuel pellets. It releases toxic
fumes and ash in house fires, putting neighbors and firefighters at
extra risk. The ash from a burned CCA patio deck is not managed as the
hazardous material it is.

The argument from the treated wood industry has been that the arsenic
does not leach from the wood fiber under normal soil conditions. While
this is somewhat true, it is misleading. The wood will _eventually_
decay and leach its metals and there is currently no safe disposal. The
practice of burning wood scraps and the mismanagement of the wood both
residentially and commercially has resulted in airborne arsenic levels
increasing nationwide, especially in the major cities where scavengers
burn scrap wood for heat.

Most uses of the wood such as decks, fences, and stakes are not
necessary for such extreme wood treatment. Only in the Southeast is the
potential of climate high in promoting decay. There is no need for
treated wood at all in the west, except on the northwest coast. Because
of these concerns, but primarily due to the threats of the wood to
commercial organic wood recycling, I am recommending that the product
only be sold or used by licensed and trained professionals, similar to
other hazardous pesticides, and that it be banned from non-hazardous
land disposal sites.

Mr Compost~~~

Jim~ McNelly
ReSourceNet and GardenNet 612-654-8372, 656-0678 v.32bis
[email-masked]
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 * April 9th - A bird in the hand craps on the wrist.