The Sensible Environmentalist
New Treated Wood Options
(NAPS)�DEAR DR. MOORE:
I love the look of a wood
deck, but I need something
that resists moisture and termites.
Is treated wood safe?
Yes, absolutely. There are a
number of treated wood products
that are highly effective at resisting
bugs, mold and
rot�and are also
safe in terms of
human health and
the environment.
Over the last few
years, there has
been some concern
about lumber treated
with CCA (chromated
copper arsenate). CCA has
been used successfully for decades.
But, because it contains arsenic,
people began to question whether
small amounts could leach out of
the wood and cause harm. As a
result of this concern (and please
note that the science itself is inconclusive),
CCA is no longer available
for residential use.
In its place are a number of
alternatives, but the most popular
are ACQ (alkaline copper quat),
CBA (copper azole) and SBX
(sodium borate)�all approved by
the U.S. Environmental Protection
Agency (EPA). For outdoor
use, ACQ and CBA are recommended,
as borate becomes less
effective when repeatedly exposed
to water. However, if you�re building
the deck yourself, note that
ACQ and CBA are corrosive to
metal. Make sure to use galvanized
or stainless steel nails, fasteners
and connectors, so they
won�t rust and pose a safety hazard
over time.
For those who have used CCA
lumber in the past, there�s no
cause for alarm. The EPA sees no
reason to replace existing structures�
including decks and playground
equipment. The phaseout
of CCA was a precautionary measure,
taken voluntarily by the
wood industry. If you�re concerned
about exposure, the EPA suggests
applying a penetrating coating,
such as a semitransparent stain,
on a regular basis.
As a sensible environmentalist,
I agree that reducing the use of
arsenic is a reasonable precaution�
and I�m glad the wood
industry has taken the initiative
and provided other options. I prefer
wood over alternatives such as
plastic and steel because it�s
renewable and sustainable over
the long term. It also requires less
energy to produce and results in
fewer greenhouse gas emissions.