Monday, February 16, 2009

Wood Preservatives

Wooden utility poles, railroad ties, fence posts, and other materials are protected from rapid degradation by wood preservatives. In a recent reassessment report, the EPA acknowledged that these chemicals and their byproducts (dioxins, furans, creosote, hexachlorobenzene, etc.) pose environmental and human health risks. Some environmental groups are pressuring the EPA and our current administration to ban the use of these materials. Other countries have switched to alternatives that are not composed of wood (concrete, steel, recycled composites). Should the U.S. do the same? What are the risks involved in continued usage of these chemical preservatives? What are the economics involved in switching to alternatives? Do the risks merit a ban of these chemical preservatives?


  1. I found a really brief summary of the initial steps taken by the EPA against the use of heavy-duty wood preservatives, along with some of the main side-effects of the three main types of preservatives. I figured it would be a good place to start:

    In 1978 the Environmental Protection Agency (EPA) initiated a Rebuttable Presumption Against Reregistration, now called Special Review, a process evaluating the risks and benefits of the heavy-duty wood preservatives. Only chemicals that trigger serious health and environmental concerns are placed in this expedited Special Review and EPA set a four-year timeline. EPA initiated the risk assessment based on the following health effects:

    * Inorganic arsenicals - oncogenicity (causes cancerous tumors), mutagenicity (causes genetic damage), fetotoxicity (kills developing babies) and other reproductive effects
    * Pentachlorophenol (or its contaminants dioxins, furans and hexachlorobenzene) - oncogenicity, teratogenicity (causes birth defects) and fetotoxicity
    * Creosote - oncogenicity and mutagenicity

    The process was not complete until 1986, four years behind schedule. The outcome was far from satisfactory from a human and environmental health perspective. EPA allowed the continued use of all of the heavy-duty wood preservatives.

  2. Katie captured part of the situation with wood preservatives. These chemicals are obviously long residual and provide long-term protection of the treated woods. They were reviewed by EPA because many were implicated as carcinogens. The EPA chose not ban them from further use following this review. Yet, as Katie notes, the outcome was far from satisfactory in terms of human and environmental health risks.

    Today, we began discussing this issue. As you can see, we will again be involved in a risk assessment. This time, the assessment will likely include environmental impacts as well as human health impacts. In addition, this assessment will include a strong economic consideration.

    We agreed upon delving further into several aspects of the issue. These are: (1) What are the preservatives that are targeted? (2) What are the risks of these preservatives to (a) human health and (b) environmental impact? (3) What alternatives are perhaps available or could be developed for these preservatives? (4) What is the cost of replacing preservatives with any viable alternatives?

    Dr. Dan Suiter will visit with us next Monday to discuss some issues. Please post to the blog as he will be monitoring our activity and may also add a comment or so.

  3. In preparation for Monday's discussion, I suggest folks look at two sites to get an overview of what I'll talk about: (Railway Tie Association), based right here in Fayetteville, GA, and page on my website where I discuss the inadvertent movement and spread of the invasive Formosan subterranean termite in used railroad cross ties. The issue(s) we'll chat about have to do with the human-aided movement of this destructive termite, the economics behind the situation, and what can/should be done to stop the interstate spread of this invasive termite.

  4. If concrete were to be used in place of wooden light poles and a drunk driver or inexperienced driver were to have an accident with one of these poles, wouldn't there be more damage compared to a wooden pole since the concrete wouldn't 'give' as much as wood? This is just something that popped up in my little head. I would think that wood would 'give' a little more and then break whereas concrete would stay intact unless there was an extreme force applied to it. I know this is way off topic but at least I am posting a blog!

  5. LifeTime Wood Treatment is:
    Non-Toxic - The natural substances penetrate the wood fibres, permanently modifying the wood structure. Independent laboratory testing confirms that LifeTime creates no harmful residue in soils and water. LifeTime is friendly to plants, animals and people and can be used in direct contact with garden soil.

    Easy to Use - A powder concentrate available in 3.8 liter/1 gallon and 19 liter/5 gallon packages. Just mix with water. Apply to bare, untreated or pressure treated wood using normal application methods. An all-purpose treatment for all new wood without need for maintenance. There is no need to ever scrape, re-stain or worry about fading and wear.

    Inexpensive - The suggested retail price for 3.8 litre/1 gallon package of concentrate is $17.95 CAD. In powder form, LifeTime can be stored indefinitely. Because you only mix what you need, you will never have large amounts of LifeTime solution left over.

  6. This is just something else I found on the internet.

    Lawsuits Filed Against Georgia Utility Pole Plant Over Health and Environmental Concerns
    (Beyond Pesticides, September 10, 2007) After years of failed political maneuverings, residents in East Point, Georgia have taken legal action case against a local utility pole manufacturer. More than 200 residents near the William C. Meredith Co. on Lawrence Street near downtown have signed onto three lawsuits complaining about noxious odors and dangerous chemicals. The latest, filed in mid-August in Fulton County Superior Court, adds another five dozen plaintiffs to the growing list. The first suit was filed in May. Neighbors to the plant are particularly concerned with creosote and pentachlorophenol, which Meredith uses to treat its utility poles. The two oil-based wood preservatives rank with the most deadly chemicals on the market, and the Environmental Protection Agency (EPA) has classified all of the chemicals, as well as their contaminants, as known or probable carcinogens.


  7. Kelley brings several different issues to our discussion. Thanks Kelley.

  8. Kelly's comment about concrete poles brings up a point that perhaps we can discuss in light of termite attack and damage to wood utility poles. Many treatments leave the center of poles susceptible to termite attack (lack of full chemical penetration). Switching to concrete is a viable option, but at what cost(s)?

  9. This is a test to see if I can post to this blog. Had no luck yesterday. If so, I'll post something a little latr today.

  10. According to Beyond Pesticides, in an article dated December,2001, Greenpeace, along with 12 other organizations, petitioned the EPA to cancel the registration of pentachlorophenol (penta). Everything I have in this comment comes from this article. In 1984, nearly all non-wood uses of penta were banned because of fetotoxicity (toxicity to fetus) and oncogenicity (tumor formation)and the availability of viable substitutes. According to the article, less toxic, economical and effective alternatives to penta-treated wood products are readily available.

    Penta is a chlorinated hydrocarbon and is contaminated with several carcinogens, including tri- and tetrachlorophenol, hexachlorobenzene (HCB), dioxins, and polychlorinated dibenzafurans (furans). Dioxin has been listed by the NTP (National Toxicology Program) as a known human carcinogen. Furan "is reasonably anticipated to be a human carcinogen based on evidence of malignant tumor formation at multiple tissue sites in multiple species of experimental animals." The same for HCB.

    Penta, HCB, dioxins and furans rank with the most toxic chemicals ever created and are classified as persistent organic pollutants (POPS) by UNEP (United Nations' Environment Programme).

    President Bush stated, "First, concerns over the hazards of PCBs,... (HCB, dioxins, furan) and the other toxic chemicals...are linked to developmental defects, cancer, and other grave problems in humans and animals.

    These chemicals not only persist in the environment for years and years and even decades, they also travel far beyond their initial point of release and they gain in their toxicity as they accumulate. Penta treated wood was the largest source of dioxins quantified in a nationwide study of 1995 dioxin emissions.

    Penta and its contaminants are endocrine disruptors: It interferes with hormone function. "These estrogen mimics interfere with the reproductive system, causing infertility, malformed sexual organs, and cancer of sensitive organs." Evidence is rarely as strong for most chemicals as it is for penta. It is also associated with immunological dysfunction; a number of women with histories of spontaneous abortion, unexplained infertility and menstrual disorders had elevated levels of their blood.

    The widespread use of penta treated utility poles across the country have brought children into direct contact with penta. According to the EPA, this is both hazardous and potentially deadly. Outdoor contact with penta also comes through fencing, porches, shingles, steps, and decks.

    The most common effects of airborne penta include local irritation of the nose, throat and eyes. Dermal exposure may lead to irritation, contact dermatitis, and, more rarely allergic disordes such as diffuse urticaria that cause intense itching.

    Studies prove that penta is ubiquitous in the environment and that penta is leaching out of treated wood into soil and water. In 1989, urine samples were taken from children living in a community with a chemical manufacturing plant. Penta was found in 100% of the children tested. In the early 1980s, samples were taken from approximately 28,000 people representing a cross-section of the nation; penta was found in the urine of 79% of those sampled.

    Environment Canada conducted a study. Penta was not detected in control samples taken from pristine watersheds and parklands; however, it was found at high levels in utility and railway ditches. The level of penta in soil and water was inversely related to the distance from the penta treated wood in tyhe ditches.

    I find the statement that "these chemicals not only persist in the environment for years and years..., they also travel far beyond their initial point of release and they gain in their toxicity as they accumulate" very disturbing. Although the level of penta that most humans accumulate in their bodies may not, by itself, cause cancer, penta, plus all the other chemicals we are exposed to, probably causes quite a potential for cancer. We should, definitely, find a way to reduce our exposure to toxic chemicals.

  11. here are some available alternatives...Ammoniacal Copper Quat (ACQ-A, B, C) - The preservative effects of copper are combined with a low toxicity co-biocide to achieve durability levels equivalent to copper/arsenic preservatives, with no impact on the mechanical properties of wood. A preservative containing ACQ-A is marketed under the brand name ACQ Preserve, by Chemical Specialties, Inc. (CSI)
    Amine Copper Quat (ACQ-D) - This product contains active ingredients similar to ACQ-A, B, C, but uses ethanolamine instead of ammonia as the solution carrier. Lumber treated with this preservative is marketed as NatureWood by Osmose, Inc.
    Copper Azole-Type A (CBA-A) - This new generation preservative contains copper and boron, and is marketed as Wolmanized Natural Select by Arch Wood Protection (formerly Hickson).
    Manufacturers believe that these preservatives intended for ground contact will provide similar durability as conventional CCA.
    Borate Oxide (SBX) - Boron compounds are well known, non-toxic preservatives, but are water soluble. Wood products treated with SBX are not recommended for direct ground contact, but can effectively preserve wood for other applications like deck surfaces or furniture. Brand name products include AdvanceGuard lumber by Osmose, Inc.and SmartGuard products from Louisiana Pacific.

  12. recycled steel poles-The Swedish report credits steel poles with a life of approximately 80 years and indicates that the reuse rate "almost reaches 100 percent, resulting in a reduced energy utilization in the processing phase from 10,000 kWh/ton to 1,700 kWh/ton.8 The steel utility poles are either galvanized or coated with a sealant.

    International Utility Structures, Inc. (IUSI) in Baceville, AR and Valmont Industries in Valley, NE have gotten into the steel utility pole business in the last several years. For a 40 foot, class 3 pole, they both have competitive pricing with IUSI pricing at $2659 and Valmont at $31510 (exclusive of freight). Valmont’s 40 foot, class 4 pole, which has a thinner diameter than the class 3, is approximately $260.11 IUSI produces a 40 foot, class 5 pole and charges $215.12 The material is lighter in weight than wood and the installation is similar.

    Reinforced concrete is also identified as an alternative material to treated wood poles.StressCrete, a company based in Burlington, Ontario, Canada (with a plant in Tuscaloosa, AL) is a major producer of cement utility poles. It charges $375 for a 40 foot, class 3 pole and $350 for a 40 foot, class 4 pole (exclusive of freight). Because of i ts weight its installation costs tend to be higher than other alternatives. However, its durability is proven, having a track record of surviving hurricanes in the southeastern U.S.

    The other pole material that most commonly surfaces is made from fiberglass reinforced composite (FRC). Burying utility lines is often considered as an option for aesthetic reasons or in areas with utility or telephone companies are trying to avoid severe weather conditions. Although cost is a major consideration, the burying of lines is currently accompanied by the use of chemical treatments to protect lines from decay and pest problems.

  13. Wood preservatives are often over looked as far as being an environmental hazard. On December 31, 2003, the wood treatment industry and the EPA voluntarily stopped treating residential lumber with Arsenic and Chromium. Industrial preservatives are generally not available to the public and they do require special permission to use by the EPA. These preservatives are used on lumber to help save our forestlands. Which I think if we can save more trees by making lumber last longer it will definitely benefit us in the long run. Preservatives that are pressure treated are classified as pesticides. Chemical preservatives are classified in three categories, water-borne salts, oil-borne, and light organic solvent preservatives. Copper Naphthenate is one of the now safest and most widely used preservative in lumber, power poles, and fence post. It is pressure treated and has a light green tent solid through the wood. It prevents dry rot, mildew, mold, and wood destroying bacteria and fungi.
    Borate is another type of preservative. It is of low toxicity to humans, and doesn’t contain copper or any heavy metals. However, it doesn’t stay in the wood as good as some of the other preservatives and may leak out. This treated lumber should not be exposed to rain, water or ground contact. Creosote is a tar based preservative that has been used on power poles and crossties. It is one of the oldest wood preservatives, and it is highly toxic. Linseed oil is not as effective but it is a cheaper preservative. There are some natural wood preservatives but they have not proven as effective as the chemical preservatives.
    We have some old fence post that has been in the ground for over 20 years and they are still solid. The wood is from a black locust tree. It is very hard and it is resistant to rotting. For environmental factors, the locust wood is a lot safer than using chemical preservatives that leak into our soil and sometimes into our drinking water. A simple solution to me would be to sleeve any wood that is being put into the ground. This would stop rot and leaking preservatives. It would cost more money but the heath cost would be greatly reduced.

  14. Several aspects of this issue have surfaced in your postings. Now, we need to begin to dig out some details, to determine facts, and assimilate scientific-based information. Health impacts have been implicated. Options have been listed. Costs have even been introduced. Yet, we'll need to do more to pull out the details and make educated comparisons. Dr. Suiter will give us a different perspective on Monday, and he will likely be able to answer a few questions that you may have.

  15. Creosote, pentachlorophenol,and inorganic arsenical pressure treated wood {Chromated copper arsenate(CCA)} are the three primary methods for current wood treatment. I found a list of guidelines given when using these harmful chemicle treated woods.


    Do not use treated wood under circumstances where the preservative may come in contact with food or animal feed, like food containers.

    Do not use treated wood for cutting-boards or countertops.

    Only treated wood that is visibly clean and free of surface residue should be used for patios, decks and walkways.

    Do not use treated wood for construction of those portions of beehives which may come into contact with the honey.

    Treated wood should not be used where it may come into direct or indirect contact with public drinking water, except for uses involving incidental contact such as docks and bridges.

    Dispose of treated wood by ordinary trash collection or burial. Treated wood should not be burned in open fires or in stoves, fireplaces or residential boilers because toxic chemicals may be produced as part of the smoke or ashes. Treated wood from commercial or industrial use (e.g., construction sites) may be burned only in commercial or industrial incinerators or boilers in accordance with state and federal regulations.

    Avoid frequent or prolonged inhalation of sawdust from treated wood. When sawing and machining treated wood, wear a dust mask. Whenever possible, these operations should be performed outdoors to avoid indoor accumulations or airborne sawdust from treated wood.

    When power-sawing and machining, wear goggles to protect eyes from flying particles.

    Wash exposed areas thoroughly after working with the wood and before eating, drinking and use of tobacco products.

    If preservatives or sawdust accumulate on clothes, launder before reuse. Wash work clothes separately from other household clothing.

    Specific Guidelines for INORGANIC ARSENICAL

    Wood pressure-treated with waterborne arsenical preservatives may be used inside residences as long as all sawdust and construction debris are cleaned up and disposed of after construction.


    Logs treated with pentachlorophenol should not be used for log homes.

    Wood treated with pentachlorophenol should not be used where it will be in frequent or prolonged contact with bare skin (for example, chairs and other outdoor furniture), unless an effective sealer has been applied.

    Pentachlorophenol-treated wood should not be used in residential, industrial or commercial interiors except for laminated beams or for building components which are in ground contact and are subject to decay or insect infestation, and where two coats of an appropriate sealer are applied. Sealers may be applied at the installation site.

    Wood treated with pentachlorophenol may be used in the interiors of farm buildings which are in ground contact and are subject to decay or insect infestation and where two coats of an appropriate sealer are applied except where there may be direct contact with domestic animals or livestock which may crib (bite) or lick the wood. Sealers may be applied at the installation site.

    Do not use pentachlorophenol-treated wood for farrowing or brooding facilities.

    Do not use pentachlorophenol-treated wood where it may come into direct or indirect contact with drinking water for domestic animals or livestock, except for uses involving incidental contact such as docks and bridges.

    Urethane, shellac, latex, epoxy, enamel and varnish are acceptable sealers for pentachlorophenol-treated wood.


    Wood treated with creosote should not be used where it will be in frequent or prolonged contact with bare skin (for example, chairs and other outdoor furniture), unless an effective sealer has been applied.

    Creosote-treated wood should not be used in residential interiors. Creosote-treated wood may be used in interiors of industrial building components which are in ground contact and are subject to decay or insect infestation. For such uses, two coats of an appropriate sealer must be applied. Sealers may be applied at the installation site.

    Creosote-treated wood may be used in interiors of farm buildings for building components which are in ground contact and are subject to decay or insect infestation, and if two coats of an effective sealer are applied except where there may be direct contact with domestic animals or livestock which may crib (bite) or lick the wood. Sealers may be applied at the installation site.

    Do not use creosote-treated wood for farrowing or brooding facilities.

    Do not use creosote-treated wood where it may come into direct or indirect contact with drinking water for domestic animals or livestock, except for uses involving incidental contact such as docks and bridges.

    Avoid frequent or prolonged skin contact with creosote-treated wood; when handling the treated wood, wear long-sleeved shirts and long pants and use gloves impervious to the chemicals (for example, gloves that are vinyl-coated).

    Coal tar pitch and coal tar pitch emulsion are effective sealers for creosote-treated wood block flooring. Urethane, epoxy, and shellac are acceptable sealers for all creosote-treated wood.

  16. A little more bout Borates and CCA in particuar
    (And a few naturally resistant wood types)

    When Borates are used, they have a problem with leeching out of the wood due to their high water solubility. They do, however penetrate heartwood where as CCA does not.They are also non-toxic for handling/cutting and does not need to be site treated on cut ends where as CCA does. Borate pressure treated wood can not be used in ground contact or water contact (leeching)but can be used otherwise in framing houses. It would eliminate the need for termite treatments. If all the wood was treated in the house, it would add around $2500 to the cost. Might this pay for itself being that there would be minimal neeed for termite treatments?

    Can be used in homes as long as all sawdust and debris are disposed of. It is superior in resisting leeching but does not fix properly to wood in cold weather. The chemicles should fix to the wood within 3-4 days of being exposed to warm weather (Around 70 degrees).

    Here is a list of some wood types that are naturally resistant to decay:

    Cedar,redwood,bald cypress (old growth), catalpa, black cherry, chestnut, Arizona cypress, junipers, black locust, mesquite, red mulberry, burr oak, chestnut oak, gambrel oak, Oregon white oak, post oak, white oak, osage orange, sassafras, black walnut, Pacific yew.

    B. Tarakanadha1*, Jeffrey J. Morrell2, and K. Satyanarayana Rao1

    The results of the study indicate that the impact of CCA preservative on epi-biotic
    community in the sea is negligible. The total number of individuals, biomass and growth were
    actually higher on CCA, CCB and CDDC treated panels compared to control ones. This suggests
    that leached components of the preservative had no adverse effect on fouling organisms. This is in
    agreement with earlier studies conducted in temperate regions

  18. The general guidelines that Steven posted on the usage and handling of woods treated with preservatives indirectly underscores the impacts that these chemicals may have in terms of human and other animal health issues. There also is some reference to environmental impact. Thanks Steven for these points.

    Jessie also added results of a study conducted on the impacts of several preservatives on aquatic organisms.

    Then, today, Dr. Suiter introduced an entirely different direction for our consideration on this issue. His information on the Formosan termite and its spread via infested railway ties helped to focus the issue on real-world and in our own "neighborhoods" and communities. This also brought in impacts on business and local economies. We talk of alternatives, but what are the costs of these alternatives, and can they be afforded?

    This week's posts should focus on details. Please add your thoughts as we move toward a final discussion on this topic during next week's class period.

  19. amtrak started trying concrete railroad ties back in the late seventies. the stress of 75,000lbs made the ties get hairline cracks. the ties are made with steel rebar. to reduce the cracking, amtrak tested tie pads that go between the rail and the tie to reduce heavy stress loads. most of these ties are being installed out west and in the north.
    in sleaving the power poles and fence post, if someone could come up with how to get the water out of the wood before the sleave is put on rot will not take place. the entire pole could be wrapped with plactic srink wrap for a tight fit.

  20. The major wood preservatives, including pentachlorophenol (penta or PCP), creosote, and arsenicals, are ranked among the most potent cancer agents, promoters of birth defects and reproductive problems, and nervous system toxicants. They contain chemicals that in other contexts are labeled hazardous waste because of the dioxin, furans and hexachlorobenzene contaminants that are found in them. Penta is used to treat 45 percent of wood poles in the U.S. Treatment of utility poles represents 93 percent of the remaining uses of pentachlorophenol. After crossties, poles are the largest wood product still treated with creosote. Forty-two percent of wood poles are treated with inorganic arsenicals and 13 percent are treated with creosote.4

    The sole purpose of these chemicals is to preserve by killing living organisms. Because they easily move in air, water and soil, they threaten human life. In addition to causing both short- and long- term health effects -- from extreme irritation to nerve damage to spontaneous abortions to death, penta and creosote are linked to disruption of the endocrine system. This means that they can disrupt the basic messages of life, affecting sexual traits, fertility, reproduction and the functioning of the nervous and immune systems. These estrogen mimics have been linked to breast cancer and prostate cancer. Regarding environmental impacts, these chemicals contaminate the soil, leach into groundwater and move through the air. Because of these effects, in many contexts the use of these chemicals is severely restricted or banned in the U.S. Twenty-six countries around the world have prohibited the use of penta.

  21. Chronic health effects–Effects of long term exposures to small quantities
    Wood preservatives are known to cause a variety of chronic health effects, though copper naphthenate is mostly untested. Some of the known health effects are:
    Impair the immune system: creosote, penta, arsenicals.
    Interfere with reproduction: creosote, arsenicals, penta.
    Cause birth defects: penta, arsenicals.
    Cause cancer (EPA’s cancer classification): creosote (B1 – probable human carcinogen), penta (B2 – probable human carcinogen), arsenicals (A–known human carcinogen).
    Cause genetic mutations: arsenicals, penta, creosote, copper naphthenate.
    Interfere with hormone function: penta, creosote.
    Some chemicals can increase the chance of cancer in humans by causing changes in cells that may lead to cancer, by facilitating the growth of cancer cells, or by inhibiting immune responses that arrest the growth of precanc erous cells. Because of the way cancer starts and progresses, any quantity of a cancer-causing substance increases the chance that the exposed person will get cancer. EPA assigns ratings to substances that cause cancer ranging from A (human carcinogen) to E (evidence of non-carcinogenicity). Creosote, penta, and the arsenicals all cause cancer. EPA’s cancer classifications are as follows: creosote–B1 (probable human carcinogen), penta–B2 (probable human carcinogen), arsenicals–A (human carcinogen) .

    An increased risk for cancer has been demonstrated in animals exposed to coal-tar creosote. The International Agency for Research on Cancer has determined that creosote is probably carcinogenic to humans (Group 2A).13 EPA has determined that cresols are p ossible human carcinogens.14 Animal studies show that cresols, a component of creosote, may increase the ability of some carcinogenic chemicals to cause tumors.15 Dermal exposure to creosote can increase the risk of cancer from other agents.16

    The studies indicating that human exposure to pentachlorophenol products causes cancer go back to 1978.16 They include studies of occupational exposure in the lumber and sawmill industry linking penta with acute leukemias, Hodgkin’s and non-Hodgkin? 146;s lymphomas and multiple myelomas.18

    EPA classifies pentachlorophenol as a probable human carcinogen (B2). It finds the sole human study examined by the agency to be inadequate. EPA bases the B2 classification on animal studies that find that two different preparations of pentachlorophenol c ause statistically significant increases in incidences of biologically significant tumor types in both male and female mice: hepatocellular adenomas and carcinomas, adrenal medulla pheochromocytomas and malignant pheochromocytomas, hemangiosarcomas, and hemangiomas. Other animal tests and reviews by other agencies support the conclusion of carcinogenicity.19

    The hexachlorobenzene and hexachlorodibenzo-p-dioxin contaminants in penta are also carcinogens. Agriculture Canada has concluded that the combined evidence from epidemiological studies on humans with mixed exposures to chlorophenols, dioxins, or pesticid es contaminated with these chemicals suggest that occupational exposure to chlorophenols or phenoxy herbicides increases the risk of three kinds of cancer: soft tissue sarcoma, Hodgkin’s lymphoma, and non-Hodgkin’s lymphoma.20 National Toxicolog y Program studies show the penta metabolite pentachloroanisole to be carcinogenic in rats and mice.21 EPA classifies arsenic as a class A, or known human carcinogen. Arsenic ingestion or inhalation has been reported to increase the risk of cancer, especially in the liver, bladder, kidney, and lung.22 Chromium (VI), found in some arsenicals (such as CCA) i s also classified as a known human carcinogen.23

    Effects on the Immune & Nervous System When a chemical interferes with the body’s immune system, it makes a person more susceptible to disease. Creosote, penta, and the arsenicals all interfere with the body’s defenses against disease.

    Laboratory studies find that technical grade penta causes immune suppression in animals, which has been linked to dioxins contained in penta.24

    Evidence in both animals and humans suggests that arsenic suppresses the immune system.25 Neurotoxic chemicals affect the nervous system in various ways.

    Both arsenic exposure and penta exposure are associated with disturbances and degeneration of nerves in the peripheral nervous system–causing, for example, numbness and a sensation of “pins and needles.”26

    Reproductive Toxicity and Teratogenicity Chemicals may interfere with reproduction in different ways–by causing infertility, death of the fetus (fetotoxicity), low birth weights, or birth defects. Creosote, penta, and the arsenicals all interfere with reproduction, and/or cause birth defects.

    Mice fed benzo(a)pyrene, one of the components of coal tar creosote, during pregnancy had difficulty reproducing, and so did their offspring.27

    Experiments in rats and mice have shown creosote to be teratogenic.28 Birth defects have been seen in livestock exposed to wood treated with coal-tar creosote.29

    Animal experiments indicate that chronic exposure to pure pentachlorophenol affects reproduction and induces birth defects.30 EPA has concluded that penta and possibly its hexachlorodibenzo-p-dioxin (HxCDD) contaminants cause birth defects and fetotoxic e ffects in test animals.31 Reported adverse effects in fetuses from penta exposure include distorted sex ratios, increased incidences of resorbed embryos, skeletal anomalies, subcutaneous edema (excessive fluid), reduced survival, and reduced growth. Sever al studies of rats and mice have shown birth defects due to the penta contaminant HCB, including changes in rib development and cleft palate formation in rats. Kidney malformations and decreased body weight were also noted.32

  22. All of the information that I have posted can be found at

  23. According to the Leukemia & Lymphoma Society, Non-Hodgkin Lymphoma (NHL) is the fifth most common cancer in the US. The age-adjusted incidence of NHL rose by 79% from 1975 to 2005, an average annual percentage increase of 2.6%. Out of the anticipated new cases in 2008 in the US of 74,340, 66,120 will be NHL. NHL's 5-year survival rates are much less than those of Lymphoma. The chances of acquiring NHL rise greatly the longer one lives, from 2.9/100,000 at ages 20-24 for males, and 1.9/100,000 for females. By ages 60-64, they are 53.9/100,000 for males, and 39.2/100,000 for females. This could be due to a general weakening of the immune system as one ages, as well as a buildup of toxins in one's body over time. As stated im my comment above, one of the concerns about penta and related toxins is that they travel far beyond their initial point of release and gain in toxicity as they accumulate. Most cases of lymphoma have no known cause. However, it has been determined that a rural lifestyle and the occupation of farming (fenceposts?) have been associated with an increased risk of lymphoma. Exposure to certain chemicals contained in herbicides and pesticides in such settings are suspected of playing a role, but these specific relationships are still under study. Perhaps they should add penta, etc., to their study.

  24. More about concrete ties (Cost benefit analysis)

    Creosote treated ties= $28.00 each or $7.50/Cu.ft.

    Concrete ties= $41.00 each

    Concrete ties often help in the
    curving segments of heavy haul railroads where its weight and rigidity help to keep the rails in
    Concrete ties, however, have very different mechanical properties, such as in flexibility,
    that mean they cannot safely be inserted into sections of rail with wood ties.Concrete railroad
    beds require more ballast rock and heavier rails than wood railroad beds but slightly fewer ties
    are required.

    A mile of new track using creosote-treated wood crossties costs approximately
    $236,000. A mile of new track using concrete crossties costs about $308,000, approximately
    30% more than with wood ties.

  25. Judging by the little bit of info we have on concrete ties, I dont think this is a good route to take at this day in age. I can surely see it developing into a more cost efficient,thriving industry (that is concrete railroad ties) but for now it seems it is not a very efficient alternative to wooden ties.

  26. In yesterday's session, Trent captured well the views on this topic. It is far more complicated in terms of the various issues involved in this topic and its eventual "resolution" than our previous topic. Toxic preservatives, alternatives, economic impact, environmental impact, human health, societal benefit, restricted uses, etc., are all involved. It's not an right/wrong scenario for most, but let's see where we can take this as we conclude this issue. I will place separate posts on some details that we discussed in class yesterday. Katie, Kassie and Kelley will be developing the final report paper on this topic.

  27. All in the class agree that wood is an integral part of our homes and other structures, utility and communication infrastructures, and railway travel and commerce. Preservatives are necessary to slow the natural degradation of woods in the environment, especially those in contact with soil. Here are some comparisons to consider.

    The USDA Forest Service conducts continual tests of preservatives on wood in soil at several locations like the Canal Zone in Panama, along the US Gulf Coast, and in Wisconsin. They report that southern pinewood that is not treated with any preservatives has an average "life" of 1.4 to 2.1 years in southern Mississippi, 1.2 years in Panama, and 4 to 6 years in Wisconsin.

    The life of pinewood in Mississippi following pressure treatment with copper arsenicals or pentachlorophenol is ~17 years, with coal tar creosote is 48.5 to 49.5 years, and with borates is 4 years. When the wood is treated with a superficial application (not pressure treated) of creosote, pentachlorophenol or copper arsenicals, the wood life is only 1 to 4 years longer than the untreated woods.

    This information is reported in Crawford et al. 2003. Comparison of wood preservatives in stake tests: 2000 progress report. USDA Forest Service Research Note FPL-RN-02. 124 p.

    The message here? The copper arsenicals, pentachorophenol and creosotes are beneficial in terms of substantially extending the life to wood.

  28. Health issues? Several posts and class discussions outlined a number of health problems associated with the heavy duty preservatives, like the inorganic arsenicals, pentachlorophenol, and creosote.

    The chromated copper arsenicals (CCA) are known to be oncogenic (tumor causing), mutagenic (genetic mutations), and fetotoxic (fetal deaths). Pentachlorophenol (PCP) and its derivatives (dioxans, furans, hexachlorobenzene) are oncogenetic, fetatoxic, and teratogenic (causes birth defects). And, creosote is mutagenic and oncogenic.

    Based largely upon these health risks, the EPA restricted the use of these preservatives to commercial only - not residential. Far less toxic chemicals, like ammonical copper, amine copper, copper azole, and borate oxide, are used to preserve woods for residential uses.

    CCA, PCP, and creosote are largely restricted for use as utility poles and railroad ties. Is the general population then not exposed to these chemicals? A study conducted in the 1980s in which 28,000 people were tested for pentachlorophenol yielded 79% of those tested had PCP in their urine! A Canadian study detected no PCP in pristine surface waters, but water along railway or utility line right-of-ways contained high levels of PCP.

    Yet, in its recent Special Review, the EPA determined that CCAs, PCP and creosote contribute benefits to society and are eligible for re-registration and continued use in nonresidential settings. That report further noted that health risks are largely occupational exposure (treatment plant workers) to all 3 chemicals and ecological exposure to PCP and creosote. (US EPA. 2008. Creosote and its use as a wood preservative. US EPA Fact Sheet.)

  29. Are there viable alternatives to the use of wood in railroad ties and utility poles? Sweden and some other countries have replaced wooden utility poles with steel. Concrete and other materials are being tested and compared for use as railroad ties and utility poles. What factors should be key in assessing the viability of an alternative?

    Economics? A 40-ft utility pole made of wood and pressure treated with a preservative is reportedly 33-40% cheaper to produce than a reinforced concrete pole, 45-70% cheaper than composite fiberglass, and 55-60% cheaper than steel. And, Steven cited stats that concrete railroad ties are 30% more expensive than creosote-treated ties and are more subject to breakage and cracks.

    Durability? Wooden utility poles weigh 1100 lbs each and need to be replaced every 25-30 years. Steel poles weigh 650 lbs and need to be replaced every 50-60 years. Concrete poles weigh 4000 lbs and need to be replaced every 45-50 years.

    Carbon Footprint? The energy required to produce and transport utility poles are 1100 megajoules for pressure-treated wood, 9710 megajoules for steel, and 13,300 megajoules for concrete.

  30. Add any additional comments and thoughts as Kelley, Kassie and Katie complete their report on this issue. Our timeline will be to discuss the rough draft of their report during our next class meeting - March 16. We'll get a survey or poll of your views and opinions on this issue to finalize that draft during the following week.

  31. Cost seems to be a big factor in the replacement of RR ties and utility poles, why not start by replacing those closest to watersheds ie:rivers, streams, lakes. A study should then be done to determine if a reduction in chemical levels occurs. I think this would be a feasable start to resolving the issue at a fraction of the cost of total replacement.

    Question** How many of these chemicals are used in the manufacture of ather products?

    ** Are we exposed to these chemicals from other sources?
    Creosote is used as a wood preservative and in some pesticides, Pentachlorophenol was once widely used as an herbacide until banned in 1987,and also some pesticides. Human exposure can occur through air born particles and drinking water. I don't think these points were brought up in the discussion.

  32. Okay, so I know we've mentioned using "composites" but I didn't really know what that meant. So I looked it up and just in case anyone else was in the dark with me, I'll post what I found.

    Composite materials (or composites for short) are engineered materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure.

    So I was thinking plastic kind of composites, but it's more general than that. Plywood is an example of a common composite.

    Then I looked up plastic composites and I found wood-plastic composite. It says that they are made from recycled plastic and from wood wastes. I think that sounds good so far because if we don't use that stuff somehow, it's just going to pile up anyway. So why not go ahead and put it to good use? The problem with the wood-plastic composite is that it's very hard to recycle for any other use. BUT, it can easily be recycled and reused for the same thing again.

    They are moisture-resistant and resistant to rot, although they are not as rigid as wood and may slightly deform in extremely hot weather.

    I'm not sure how they are as far as termites and pests and stuff, but if they're moisture and rot resistant, I would think that bag idea would work- the thing about keeping the soil from touching the electric poles.
    I would also think that the flexibility might be good for the railroad ties. Not sure how the termite thing would work though.

    Plastic and wood composite lumber needs no maintenance or sealing and does not rot, chip or warp. It is also impervious to insects Composite products have guarantees ranging from 10 to 50 years.

    Okay, so now I know that the wood/plastic composite is resistant to instects.

    I don't know much about this kind of stuff, but I really can't see a problem with using the wood/plastic composite. Maybe cost, but no matter the cost I think it would be worth it.

  33. Oh and as far as utility poles go, I'm definitely in favor of burying the lines. I think the cost of burying them would be made up fairly quickly- especially after a few storms and no damage. Also burying them would just look way better. I hate seeing some beautiful landscape or something and then there's a big power line running through it.

  34. Hello, people. Forgive my poking my nose in here. I happened on your blog while surfing for penta news. I live in the neighborhood cited in K. Cooper's post 2/18. It's heartening to read of your study and search for solutions. Keep up the good work!!
    Sincerely, Ruth

  35. Burying utilities is an option; however, the process always involves pretreatment of the ditches with a residual pesticide to help protect lines from various critters. Are we creating another problem with a solution for the other? Again, weighing risks!

  36. my brother n law is a linemen for emc. i talked to him about the utility poles and the posibility of burying all the lines in the ground. he agreed how much better it looks without lines above ground...he said the over all cost for changing the lines would be very expensive. and repairs would be much harder. digging the trenches would take much longer and much more man power. i am infavor of replaceing the above ground lines to perserve wood and the asthetics but i just dont think that any company or the gov.t could afford to do anything at this time.
    the rr ties could be made from rubber reinforced with steel for strength. the ties could be made from old used tires and that would be another waste that we could get rid of..dont know how much the cost of manufacturing would be

  37. I am having a hard time developing a position on this topic. As far as my life and anyone that I know of (to our knowledge) has not been affected by the use of wood preservatives.

    If you did not use wood preservatives then the lifetime of your wood pole is less than 5 years. At this rate deforestation would increase dramatically so I would say that wood preservatives are a necessary evil.

    Carcinogenic and toxic substances are now well established in our environment. I would guess that on a list of cancer causing products and practices and their contribution to the overall amount found in our environment, Wood Preservatives would contribute a small percentage. Our environment does have an unknown threshold for the amount of toxins that it can sustain and filter, and once we reach this point our world will change. There must be something done to start to decrease the amount of unnatural chemicals getting into our soils and water. However, the worst offenders must be dealt with first and I do not think wood preservatives should be our first target.

    I do like the idea of composite woods made from waste products like plastic bags and wood chips etc. This is the kind of overall idea we should be adopting as a world concerned about our environment because our current situation is that of use and discard. We need to continually reuse and recycle our most used necessities to give the environment a chance to catch up and replenish itself.

    If there was ever a time to figure out a solution to the use of wood preservatives it is now. Our electric grids and rail roads need a complete overhaul to make them more efficient and inexpensive for future American generations. If we keep accepting the same old business then the problems now will grow exponentially for future generations.

  38. As with all problems the solutions come with a cost. Especially in development and implementation. There is a problem in the wood preservatives used and an industry of workers that have to be kept in mind. There is no way to make every party happy but to minimize displeasure as much as possibly in each party. I think a good approach to this would be to slowly phase out the use of the wood products with the recycled composite structures that have been recently developed. The areas with high decomposition rates, high termite infestations and high moisture areas could be a good area to start. The companies that produce these wood products could move to maintain their niche in these industries by making the transitions to the production of these alternative products. From the research that I have seen the initial cost is high for these products but the long term payoff is also high due to the high life expectancy. This approach would also help in the slowing of deforestation and reducing waste materials in landfills by recycling those items for the use in the new products.

  39. my position is very clear slowly take out all the poles and go underground.

  40. The environmental impacts of wood preservatives are much cut and dry the impacts are negative to our environment and our existence on earth as a human race. Wood preservatives are pesticides that protect wood against attack by fungi, bacteria, or insects. The active ingredients found in wood preservatives may include pentachlorophenol (penta or PCP), creosote, copper, zinc, chromium, arsenic, and other compounds. Preservatives may be injected into the wood before purchase (pressure-treated wood) or applied by the user. If wood-preservative chemicals are incorporated into a paint or stain, that product is considered a pesticide.
    Wood preservatives perform a useful function and may be required by building codes in some applications. In other cases, there is a choice of whether to treat or which chemicals to use. Wood preservatives are hazardous materials, and health and environmental hazards should be considered in making these decisions. If you must use a wood preservative, compare labels and look for the least-toxic products that will do the job. Some preservative ingredients that are less toxic include copper compounds, zinc compounds, and borates, but individual product hazards vary widely.

  41. whats lifetime wood treatment made of?I found out theres dried flowers,dried mushrooms,dried basil ect ect what kind of wood preservative is this?

  42. we agree with bob , we think lifetime wood treatment is a joke and whats with the ingreidents?we found a dried up mushroom.and what looked like a small bit of basil or some other spice in our package? andy rainsford colorado, is this really a wood preservative?