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Treated Wood

Pentachlorophenol background documents

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Alternatives to penta treated poles 

15 November 2016 Power Poles Alternatives

Steel distribution poles poised for market gains The Stockholm Convention, a global environmental treaty, banned the use of pentachlorophenol for member countries in May 2015, giving the chemical a five-year phase-out period. One of the most common uses of the chemical was as a preservative for wooden utility poles.

Fact Sheet on Chemically Treated Wood Utility Poles (Beyond Pesticides, no date, I think 2002) SNAP Comment: Why put this here? Well, SaskPower will keep on installing more treated wood power poles in the coming months. The poles are treated with the cancer causing pesticide pentachlorophenol. Penta is a known persistent organic pollutant  (POP) which will be banned in 3 years because it is so dangerous to human health and the environment. Their line of defense to Radio-Canada is that penta is better than the pesticide (and toxic element) arsenic (PMRA label search-  May 2017-  indicates 10 historical and 10 registered products). The use of cancer-causing treated wood for power poles ignores available alternatives such as cement or steel poles or simply burying power lines.


Pentachlorophenol     Pesticides – Known Carcinogen (IARC 1) (Carex Canada - Surveillance of environmental and occupational exposures or cancer prevention) Pentachlorophenol is extremely toxic to humans from acute (short-term) ingestion and inhalation exposure... Rapid absorption of pentachlorophenol has been reported in rodents, monkeys, & humans following oral, dermal, or inhalation exposure...PCP binds to mitochondrial protein and inhibits mitochondrial ATP-ase activity. Thus, both the formation of ATP and the release of energy to the cell from the breakdown of ATP to ADP are prevented, etc...

PENTACHLOROPHENOL Canadian Soil Quality Guidelines for the Protection of Environmental and Human Health  1997    Recommandations canadiennes
pour la qualité des sols :Environnement et santé humaine PENTACHLOROPHÉNOL

3 March 2017 Canadian Environmental Law Association Pentachlorophenol Re: Comments and Recommendations to inform Canada’s position to the Conferences of the Parties (COP) to the Stockholm and Rotterdam Conventions April 24 – May 5, 2017 in Geneva, Switzerland. The following comments and recommendations focus on the Stockholm Convention on Persistent Organic Pollutants and the Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade. In 2015, Pentachlorophenol (PCP) was added to Annex A (elimination) with specific exemptions from COP9. However Canada has made no commitment to ratify PCP.

April 21, 2015 NGO Letter on HCBC CNand Pentachlorophenol Canada 'The (POPRC) determined that pentachlorophenol (PCP) meets scientific criteria as a POP for its persistence, bioaccumulation, and adverse effects and that it will, as a result of its long-range environmental transport, “lead to significant adverse human health and environmental effects such that global action is warranted.”'

18 November 2016 Utility Poles and the Threat to our Health by Giampa Law. The International Agency for Research on Cancer, part of the World Health Organization, has classified the chemical as Group 1, carcinogenic to humans. Penta has been linked to an increased risk of certain cancers-such as non-Hodgkin's lymphoma, kidney cancer and multiple myeloma-especially among sawmill and utility workers who have regular exposure to the chemically treated poles. People can be exposed to the chemical if it contaminates the soil, leaches into groundwater or moves through the air. But the risk of exposure is clear. A research paper published in January 2015 in the International Journal of Environment Research and Public Health found that penta had been "detected in air, soil, carpet dust, food, and hand wipes samples collected at U.S. homes and childcare centers" and that nearly all of the children in the study had been exposed to penta daily.

Updated: June 29, 2016 Alaska Arctic Indigenous  by Vi Waghiyi. This letter thanks for a reduction in Persistent Organic Pollutants (which include pentachlorophenol) which accumulate in Arctic and contaminate the food chain. "Persistent organic pollutants are chemicals that persist in the environment and bio-accumulate through the food web. They contaminate our human blood and breast milk without our consent, and are associated with a range of harmful health effects including learning and developmental disabilities, endocrine disorders, and cancers. Accumulation of POPs in northern latitudes is a well-documented phenomenon."

Pentachlorophenol (IPCS InChem)  
4.3 Occupationally exposed populations includes walking with bare feet through areas where PCP was sprayed, addition of PCP to cellulose products, such as starches and adhesives and industrial cooling towers and evaporative condensers. SNAP Comment: the last 2 exposures come from reuse of the treated poles. As skin exposure is so important, just touching a pole is enough for a person to absorb PCP. 9.2.2 Inhalation Virtually all workers exposed to airborne concentrations take up PCP through the lungs and skin. 9.2.3 Skin exposure In addition to airborne concentrations, workers who handle treated lumber or who maintain PCP-contaminated equipment are at risk pf absorption of PCP via the skin. They may absorb from 50% (based on urinary PCP levels) to 70% (based on serum levels) of their total PCP burden through their skin. also lists 7.2.5 Acceptable daily intake (ADI)

Pentachlorophenol (US National Library of Medicine, PubChem Open Chemistry Database)

Pentachlorophenol  RISK PROFILE OF PENTACHLOROPHENOL. Dossier prepared in support of a proposal of pentachlorophenol to be considered as a candidate for inclusion in the Annex I to the Protocol to the1979 Convention on Long-Range Transboundary Air Pollution on Persistent Organic Pollutants (LRTAP Protocol on POPs) (Institute of Environmental Protection) (Institute of Environmental Protection, Warsaw, May 2008)  SNAP Comment: Since then, pentachlorophenol had ben classified as a definite human carcinogen, and is due to be phased out internattionally in 2020 with possible exceptions. Good background document explaining aerial transport, half life, bioaccumulation, previous and current uses, environmental levels and bioavailability (section B.) socio-economic factors (section C.) including regulations, substitutes, 4. Factors relevant for utility line construction and maintenance affecting utility poles selection and 5. Importance of wooden utilty poles in the USA. Although energy-wise, wooden poles require significant less energy to produce, their safe disposal is an issue. The conclusion is "we recommend to include the pentachlorophenol on the POP’s list requiring harmonized international actions with the ultimate goal to ban PCP and its salts production and uses."

Pentachlorophenol poisoning. (Proudfoot AT. Toxicol Rev. 2003;22(1):3-11.)

Chapter E – Pentachlorophenol Pressure (PCPP) Wood Preservation Facilities    Chapitre E - Installations de préservation du bois au pentachlorophénol sous pression (PCPP) look for 3. Environmental Effects.

Treated Wood Disposal

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Industrial Treated wood users Guidance Document (Environment Canada) An appaling document! First stating  "In general, treated wood originally used in industrial applications should not be re-used in the residential market. This includes uses such as landscaping timbers, used railway ties,and garden furniture. Further, the re-use of treated wood should be avoided in products which may become building materials for residential homes where there is potential for exposure of the residents to the treatment chemicals. This caveat excludes the registered use of CCA treated plywood for wood foundations." (7.3 Recommendation 8). Then presenting  7.4 National Strategy for the Management of Post-Use Preservative Treated Industrial Wood (adapted from Konasewich et al., 2001) which describes as good options the exact same things they say should not be done in 7.3: producing landscaping timbers, used railway ties and garden furniture out of pentachlorophenol treated poles and railroad ties, mixing chipped treated wood with other waste wood fibre in order to make a heavy dry felt paper product which is then used as a base for asphalt roofing shingles. The also advocate the option of  burning in industrial boilers and co-generation facilities, and one cement kiln which will not destroy the toxic chemicals and dioxins and help spread the pollutants far and wide. Option 5, Hazardous waste incinerators which used to be the proper way to handle these pollutants now do "not support the concept of sustainable development." Finally option 6:landfilling. During the year 2000, approximately 12% of railway ties and 13% of utility poles that were taken out of service were disposed of in landfills throughout Canada.

Disposal of Treated Wood (Jeffrey J. Morrell, Oregon State University, Corvallis, Oregon 97331, conference presentation). Looking at treated wood use and disposal challenges in the USA. "The chemicals in these products do not biodegrade and large quantities remain in the wood that is disposed. Finally, the user has little knowledge of what constitutes proper disposal." About power poles: "For decades, utilities disposed of used poles in a variety of simple ways including give-aways to adjacent landowners, donations to civic groups and when all else failed, leaving the cutup pole by the side of the road where it mysteriously disappeared."  SNAP Comment: This give away is part of what the treated wood industry calls "recycling".

Many pesticides are licensed in Canada for treating wood, including pentachlorophenol (utility poles), creosote (railroad ties) and CCA (Chromium Copper Arsenate) which was the most common wood preservative for home use and also used for utility poles. These three pesticides are or contain known cancer-causing agents. Pentachlorophenol is also an endocrine-disruptors. All three have been under review for decades by the US EPA and the PMRA.

As of 10 May 2017, there are still 2 commercial products containing pentachlorophenol registered in Canada, and 5 containing creosote.

May 5, 2017 Answer to SaskPower' Sask Power's 2017 Wood Pole Maintenance Program blog post. SaskPower is going on with business as usual by replacing toxic posts with more toxic posts because that is what they have always done. The difference between then and now is that NOW, we KNOW about the health and environmental risks of pentachlorophenol. In 2015, penta was added to Annex A (elimination) of the Stockholm Convention on Persistent Organic Pollutants and, in three years, the chemical will be phased out. Poles are being planted now that are going to be giving off toxic penta for 50, 60 or 70 years to come. Is ths acceptable? Adding the cost of over $8000 of incinerating each post and the health and environmental costs to the purchase cost should make it obvious that new posts that SaskPower installs are either steel or concrete. Thanks to Yvonne for putting this issue on the map. Please tell SaskPower to install posts made of steel or concrete rather than pentachlorophenol treated ones, or bury lines. SNAP correction (10 May 2017): It appears I was wrong about disposal. Now incinerating toxic treated wood at high enough temperatures to destroy at least part of the toxic pollutants is no longer viewed as "support(ing) the concept of sustainable development."  It appears that, after stating that industrially treated wood should not be used in and around homes (1,  7.3 and 7.4), several Canadian companies are licensed to do just that producing garden furniture, fencing and landscape lumber.. Instead we also favour burning  penta (or PCP) treated wood for energy, therefore distributing the pollutants far and wide. It seems to me that sustainable development would require that we replace unsustainable toxic materials with new ones that are not so toxic...

Label Warning on Dangerous PCP-Treated Poles Deemed Unconstitutional (Beyond Pesticides, March 3, 2016) Last month, U.S. District Court Judge Arthur Spatt declared a dangerous wood preservative label ordinance unconstitutional, ending a three year battle between a New York town and Public Service Enterprise Group (PESG)...Because the utility poles are not intended to be sold to the public nor influence consumer behavior, PESG is not required to post “compelled warning signs” on their dangerous utility poles. Pentachlorophenol (PCP) is a recognized cancer-causing wood preservative. As of March 4, 2016, there are still 3 products registered in Canada for commercial use. It is commonly used for railroad ties and utility poles. I have not heard of any efforts to have a mandatory toxicity label in Canada.

International Treaty Bans Pentachlorophenol, U.S. Continues Use on Utility Poles and Railroad Ties (Beyond Pesticides, May 18, 2015) Delegates from more than 90 countries took the unprecedented step of voting last week for a global ban on pentachlorophenol (penta) – a proven toxic pesticide and contaminant found in wildlife and human biomonitoring studies worldwide. There are still 2 pentachlorophenol products registered in Canada as of June 2015. Posted in SNAP's treated wood

Treated Wood EPA and PMRA Reviews (June 17, 2008)  SNAP signed on to the following treated wood comments from Beyond Pesticides to the US EPA. It is relevant to do so as the products are under co-operative re-evaluation, and the US re-evaluations is poorly done. 

Beyond Pesticides comments to the U.S. EPA.  SNAP’s comments to the PMRA as well as an endorsement of the Beyond Pesticide comments to the PMRA.