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PROBLEMS PRESENTED BY WOOD ASH.

The wood ash that remains from the burning of pressure treated wood is a very real and toxic problem. This ash contains 80% of the toxins that were contained in the wood. This ash is highly " leachable" and can contaminate ground water if buried. There have been several incidents reported where this ash has caused, sickness, death and contamination. One is an incident that happened to a herd of cows on a dairy farm. Here is the story as reported in This Old House Magazine. "Dairy farmers Peggy and Jim Janson of Saulk Rapids, Minnesota, had to replace 18 Holstein heifers after a thunderstorm spooked them over a fence and into a neighbor's farm. Jim retrieved them, but they all died within four days. State investigators determined that the cows died of internal bleeding and liver failure caused by arsenic poisoning. They traced the arsenic to ash dumped on the neighbor's land after someone burned scraps of pressure-treated wood to heat a house. Preservatives made the ash taste salty, which attracted the cows. Mike Murphy, a University of Minnesota veterinary toxicologist, found that 5 tablespoons of the ash has enough arsenic to kill a 1,100 pound cow; a single tablespoon can kill a 150-pound human. "I don't think people really understand how dangerous pressure treated wood can be when it's burned," Murphy says."

Another incident reported in this same article concerns a sugar cane farm. It states that "rather than destroying the arsenic, chromium and copper, fire concentrates them in the ash. Burning even a small amount of the wood with other debris is enough to turn all the ash into hazardous waste, as owners of the Okeelanta and Osceola sugar mills in Palm Beach County, Florida, discovered after they began running a co-generation power plant to produce electricity as well as steam for refining sugar. Half the year the plant burned primarily sugar cane waste as fuel; the rest of the year, it burned construction and demolition debris. The owners say pressure-treated wood accounted for less than 1 percent of what was burned. But when the ash was tested in 1995 and 1996, arsenic measured as high as 507.7 ppm. "It was just way off the scope," says Hinkley, the state environmental officer. "Nobody thought that little an amount of pressure- treated wood would cause a problem that big." The sugar company-stuck with 30,000 tons of contaminated ash that cannot be spread on crops-faces a $1 million dollar landfill bill."

Also in this article Bill Hinkley is quoted as saying about the ash, "We call it a threefer, it can leave you dead as a doornail at high doses. It can kill you at moderate amounts over a longer period. And it's a carcinogen at low levels."1

The following chart shows metal concentrations in the wood and wood ash and the acceptable limits of these metals in the state of Florida and the federal limits for the United States.

Table 7 Metal Concentrations in CCA-Treated Wood and Wood Ash⁴      

a Computed values assuming that retention rating equals amount of chemical in wood
b Measured values
c Federal Register 40 CFR Part 503. 13, Standards for the Use or Disposal of Sewage, Subpart B, Land Application
d Florida Department of Environmental Protection, Proposed Chapter 62-777, F.A.C. Contaminant Target Clean-up Levels
Table: Chromium, Copper, and Arsenic Concentrations in Treated Wood and Treated Ash Samples Used in This Study. Regulatory Levels Provided for Comparison.

In this article we are also told, "that the official warning label on pallets of pressure treated wood says it should not be burned in stoves, fireplaces or residential boilers. Waste wood at construction sites "may be burned in commercial or industrial incinerators or boilers in accordance with state and federal regulations," the label says. But the Environmental Protection Agency issued that statement in 1988, and incinerating pressure-treated wood is no longer legal in any state because the dangers are too great.

Because of such hazards, researchers are scrambling to find ways to extract the chemicals from scrap wood so it can be recycled safely. Using citric or other acid is too expensive, and no one wants pressure-treated fibers in particleboard. In the meantime the volume of the scrap is growing. In 2020, the years total is expected to be 467 million cubic feet-enough to build a boardwalk 3 feet wide and 1 ½ inches thick all the way to the moon. "And every piece of it is headed for the landfill," says Jeff Fehrs, an engineer with C.T. Donovan Associates of Burlington, Vermont, which finds markets for scrap wood."1

In an article from News and Analysis titled, New Technique to dispose of treated wood developed by University of Florida researchers, we learn of the continuing struggle to solve the scrap problem.

Florida's concerns are particularly high as they burn 70% of their waste treated wood in their electricity - generating wood incinerators, says C.Y.Wu, assistant professor of Environmental Engineering at the University of Florida.25

"Wu's research shows that much of the arsenic escapes into the air when treated wood is burned. That is because the pollution control devises in the incinerators smokestacks capture only relatively large particles. In the heat of the incinerator, however, the arsenic vaporizes and forms extremely tiny particles-less than 1 micron in diameter or more than 100 times smaller than the diameter of a human hair. These tiny particles can not be perfectly captured in traditional pollution devices."25

The University of Florida, in a new technique, introduced limestone into the burning process which reacts with the arsenic to form larger particles, in the range of 50 microns. Instead of escaping through the smokestack, those particles wind up in the waste ash.25

That may appear to merely transfer the problem from place to another, but Wu said tests reveal that the arsenic -limestone particles are also much less likely to leach into the groundwater than the tiny arsenic particles when placed in the landfill.25

"So far, the incinerator technique has only been tested in laboratories. But Wu noted that power plants already use a similar technique involving injecting limestone into air pollution devices to reduce sulfur dioxide emissions, which suggests adopting the process for wood incinerators is a distinct possibility.

John Schert, director of the Florida center for Solid and Hazardous Waste Management at the University of Florida's College of Engineering, said "If somebody can figure out how to burn CCA treated wood and not let the arsenic escape into the atmosphere, that's the Holy Grail for disposing of CCA wood."25

The other research team members are Timothy Townsend, an assistant professor of environmental engineering, and Kenjiro Iida, John Pierman and Thabet Tolaymat, all students in the department of environmental engineering.25

I personally believe while their work should be applauded, that the ash remaining although less "leachable", still contains 80% of the toxins and poses a serious environmental danger. Even a small amount of leaching, when you take into consideration the enormous amount of waste wood that would be burned, would cause serious problems. I believe instead of trying to fix this problem so more of this wood can be made, we should be outlawing its use and using alternatives which will be later discussed. Then perhaps their research could be put into use to dispose of what we have already unwittingly put into our environment.

Others share my opinion as can be seen in the U.S.NEWS online in an article called, Kids at Risk by Sheila Kaplan and Jim Morris. "The chemical industry prefers to police itself, when given a choice. But this approach seldom works, as evidenced by the Environmental Protection Agency's (EPA) failed attempt to restrict a pesticide known as chromated copper arsenic, or CCA. The compound is applied to pressure-treated wood and commonly found on decks and playground equipment. Since the late 1970's, EPA researchers have reported that CCA poses a special threat to pregnant women and children because it combines three neurotoxic compounds. People can be exposed to CCA by breathing fumes from unfinished wood during home repair and construction. As a structure ages, the compounds may leach out into the dirt. In lower doses, according to numerous studies, CCA can impair intelligence and memory.

The EPA tried to restrict CCA in 1984, but homebuilders' and wood preservers' groups lobbied Congress so hard that the EPA retreated, asking only that retailers distribute advisories that the compound could endanger children. A decade later, the effort had gone nowhere. "We checked retailers," said John McCauley of the Kentucky Department of Agriculture, "and they had no clue what a consumer information sheet was."18

On a fact sheet printed by a manufacturer of pressure treated wood, Exterior wood, the dangers of this wood seem to be downplayed according to my research. Even still, this is what they have to say about burning the wood. " Question - are there any special precautions that apply to treated wood and do not apply to untreated wood?" Answer "Treated wood should not be burned. If you burn the wood, you release the preservative constituents that are locked in the wood cellulose. Burning destroys the wood cellulose and the metals end up in the wood ash. If that ash is not properly handled, it could cause health or environmental concerns."20

Mark Harris brings up another point in his article titled Earth-Friendly Living: Pressure- Treated Wood Get Low Marks From the Environmentalists. I quote him, "don't burn your scraps. Burning will send arsenic laden smoke wafting throughout your house. Arsenic will collect in your ashes, tainting them, so don't spread them in the garden."19

A paper written by Henry A. Peters, MD and his research team called Seasonal Arsenic Exposure From Burning Chromium-Copper-Arsenate-Treated Wood was written on the experiences of a rural Wisconsin family of eight who had been burning scrap pressure treated wood in their home wood stove as fuel and was published in the JAMA in May 11 1984.26

This study describes in detail the health problems of this family and the tests that were done to determine the cause of their illnesses. The family did not know why they were sick nor did the investigators at the beginning. Foul play was even suspected at one time. But finally the cause was poisoning from both the wood ash and the smoke from the stove. The family's problems went on for almost four years but would improve in the summer when the wood stove was not in use.

Here is an excerpt from that paper, "An eight member family from northern Wisconsin experienced health problems involving the eyes, respiratory system, CNS, gastrointestinal (GI) tract, blood, reproductive system, skin, and hair. The exposure to arsenic, copper, and chromium occurred through ingestion, inhalation, and direct contact. This resulted in chronic exposure (1) to the skin and eyes where it caused pruritic dermatitis; (2) to the respiratory system where it caused severe irritation and some pneumonic problems (almost fatal to the fourth child); (3) to the gastrointestinal tract where it caused severe diarrhea: (4) to the CNS where it caused loss of sensation, seizures, blackouts, and headaches; and the most puzzling lesions of all, (5) the seasonal hair loss among all the family members."26

Charts showing their symptoms and hair and fingernail analysis follow. The family's many symptoms show it would be difficult for a doctors to diagnose this problem if they were not looking for it.

Table 8 Summary of Family Health Conditions During the Last Three Years²⁶

*ITP indicates idiopathic thrombocytopenic purpura

*Normal values for hair, less than 0.65 ppm; fingernails 0.9 to 1.8 ppm
a Unwashed hair
b Removed from hairbrush.
In a second paper titled Hematological, Dermal and Neuropsychological Disease from Burning and Power Sawing Chromium - Copper- Arsenic (CCA)-Treated Wood11 Peters and his team again recount the story of the Wisconsin family and the hazard of improper disposal of CCA treated lumber. They stress the need to publicize the issue. They go on to describe two case studies of workers who became ill while using pressure treated wood. These cases are discussed in the section titled Incidents Reported While Working With Pressure Treated Wood.

In an article in Weather-Bos we are told that, "the Wisconsin's environmental agency fined John Menard, owner of the 200 store Menard's home improvement chain, $1.7 million for burning CCA scraps to heat the company's lumber production facility. Menard was caught carrying the ash from that facility to his home, where he disposed of it with the family trash."2

In a report by the European Commission Health and Consumer Protection" "Assessment of the risks to health and the environment of arsenic in wood preservatives and of the effects of further restrictions on its marketing and use" expressed at the 5th CSTEE plenary meeting, Brussels, 15 September 1998 we find the following statement.

Uncontrolled burning of CCA-treated wood in homes or in open grounds is discussed in the Report and it is concluded that air emissions from such practices can give rise to increased estimated risks of lung cancer. The CSTEE notes that indeed there is direct literature documentation of acute health effects in families burning such wood in their home, the significance of this possible source of human exposure lying in the difficulty of recognizing CCA- treated old wood. Ash left over from uncontrolled burning of wood in open grounds is considered in the Report to generate unacceptably high soil contamination and, if the same site is used repeatedly, it may present a risk of ground water contamination."7

In their conclusions the Report states, " marginally increased lung cancer risks from controlled incineration of CCA-treated wood-significantly increased lung cancer risks from uncontrolled use of CCA-treated wood for home heating-significant effects on the environment from uncontrolled burning and disposal of CCA-treated wood-potential risks from the unpredictable long-term leaching behavior of arsenic in special waste landfills." The Report further recommends, "it would be advisable to exercise caution by limiting the use of arsenic- based wood preservation to those situations where it is absolutely necessary."7

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