Posted by deborah (64.230.44.75) on April 22, 2003 at 11:10:27:
In Reply to: Use of Copper Azole to pressure treat wood and its safety to the public and the enviornment posted by Harry Hakim, BPHE on March 08, 2003 at 12:10:37:
: Are there any tests that have been performed and documented about the use of CA in pressure treating wood? Does it meet or exceed safety standards American or Canadian re requirements of the PMRA (pest management regulatory authority? If so, where can I get supporting documentation.
Here is the response from the PMRA
Here is our response to your inquiry on copper azole. Sorry for the delay.
Background Information
The only currently registered copper azole product used for pressure
treatment of wood in Canada is the product Wolman NB, PCP registration
number 27132, registered by Arch Wood Protection Canada Corp. This product
was granted a temporary registration in 2002.
The PCPA regulations provide for temporary registration of a product or use
for a period not exceeding one year provided that the Agency concludes that
no unacceptable risks are expected. The registration is conditional on the
applicant agreeing to produce additional scientific or technical
information within a specified time period. When the specified data
requirements have been met, the applicant may apply to convert the
temporary registration to a regular full registration. The applicant may
also apply to renew a temporary registration, prior to its expiry, for
another year.
The product label for Wolman NB can be obtained on-line at
http://www.hc-sc.gc.ca/pmra-arla/english/index-e.html. This product
contains two registered active ingredients copper oxide (PCP registration
number 27122) and tebuconazole (PCP registration number 25763).
Copper oxide has been registered for many years as a wood preservative for
pressure treatment of wood. In addition to this use, it is registered for
use in anti-fouling products applied to boat bottoms and fishing nets.
There are several registered sources of the technical active product.
Arch Wood Protection holds the registration for the source used in the
Wolman NB product.
Prior to the temporary registration of the Wolman NB product, tebuconazole
was registered in Canada as a seed treatment fungicide on food crops
(wheat, barley, and oats). Maximum residue levels for tebuconazole have
been established for a number of other crops reflecting international
registrations of this pesticide. The only registered source of
tebuconazole technical in Canada is Bayer Inc.
Q1: Are there any tests that have been performed and documented about the
use of CA in pressure treating wood?
A1: In the process of evaluation for any end-use product, such as Wolman
NB, the hazard presented by the individual active ingredients and
formulants is considered. In addition, specific data are examined to
determine the risks associated with the use of the end-use product.
As the use of copper oxide active ingredient in the copper azole
formulation did not represent a significant change from the existing use
pattern, a new safety assessment was not considered to be necessary. While
there are many forms of copper, the copper ion is the agent responsible for
its pesticidal action and toxicity in animals. The toxicity of copper is
well studied and understood. A complete examination of its toxicity is
readily available through published scientific journals and texts. A good
evaluation document on copper toxicity can be obtained from the Agency for
Toxic Substances and Disease Registry (ATSDR):
http://www.atsdr.cdc.gov/toxprofiles/tp132.html
Risk assessments for the tebuconazole in its currently registered end-use
products (food seed treatment, use site category 10) have been conducted by
PMRA. The addition of heavy duty wood preservation use for tebuconazole,
use site category 23, was considered to be a major new use for that
pesticide. The mammalian toxicology data already available addressed the
data requirements for wood treatment. Please find Use Site Category (USC)
DACO tables 23 (tgai, eup) and 10 (tgai) attached to this response for
comparison of the required data for products in each of these use site
categories.
For the registration of Wolman NB, the PMRA considered safety data for two
closely related end-use products submitted to support the registration of
Wolman NB. Although not currently registered in Canada, these two closely
related products, Wolman 3490 (US Registration number 062190-00016) and
Wolman 3488 Wood Preservative (US Registration number 062190-00012) are
registered in the US. Wolman NB is also registered in the US (registration
number 062190-00022). A similar product is registered in Australia
(product number 46641).
Tebuconazole is acceptable for use on numerous food crops in the US [i.e.
foliar fungicide for wheat; trade name Folicur 3.6 F Foliar Fungicide; US
registration number 000264-0752][e.g. foliar fungicide for cherry, peach,
nectarine, grape, banana, plantain; Elite 45 DF Foliar Fungicide; US
registration number 003125-00388]. Numerous foliar food crop uses are also
approved in Australia [e.g. Folicur 430 SC, Australian product number
46794]. These products for foliar use of tebuconazole, are not currently
registered in Canada.
Based on the safety assessments available for the active ingredients in
Wolman NB, assessments for existing Canadian tebuconazole end-use products,
and consideration of international registrations, a temporary registration
was granted.
Labels for US registered pesticidal products can be obtained at the
following web sites: http://www.epa.gov/pesticides/pestlabels/ and
http://www.cdpr.ca.gov/docs/epa/epamenu.htm.
Labels for Australian registered pesticidal products can be obtained at the
following web site: (run search on tebuconazole)
http://www.apvma.gov.au/pubcris/subpage_pubcris.shtml
2: Does it meet or exceed safety standards; American and Canadian?
Wolman NB and similar products are registered in the U.S. Based on the
discussion presented under the background information section and in the
answer to question 1, Wolman NB is not expected to pose unacceptable risks.
3: Where can I get supporting documentation?
Under normal PMRA procedures, a consultation document would be published
when a product is proposed for full registration status. A PMRA
consultation document for this product has not yet been published.
Information can be requested directly through owners of the active
ingredients (Copper: Arch Wood Protection Canada Corp.; Tebuconazole: Bayer
Inc.) or through the owner of the formulated product (Wolman NB: Arch Wood
Protection Canada Corp.). At this time, the PMRA cannot release original
data or evaluation reports without the permission of the data owners
because this information is considered Confidential Business Information by
the data owners and protected from disclosure under the Access to
Information Act.
Supporting documentation for registered products in other jurisdictions can
be requested through the relevant regulatory agencies. The US EPA web site
is www.epa.gov/pesticides and the Australian regulatory authority can be
contacted at http://www.apvma.gov.au/.