What is Arsenic?Inorganic arsenic has been recognized as a human poison since ancient times. Arsenic is a highly toxic, naturally occurring grayish-white metal-like material. Inorganic arsenic is created when elemental arsenic combines with oxygen, chlorine or sulfur. Inorganic Arsenic has been used as a poison in pesticides and herbicides, and is still used in making CCA pressure Treated wood. An extremely toxic poison, it is colorless and odorless:Arsenic gives no warning: it does not have a specific taste or odor to warn you of its presence. How is arsenic released from CCA wood?CCA pressure-treated wood contains arsenic which can be released from the wood when the wood is burned, through mechanical abrasion (like sanding or sawing), direct contact and when acid contacts the treated lumber. See the 'CCA Wood' tab to the left for more information. Incineration of CCA pressure treated wood does not destroy arsenic. It is illegal to burn CCA wood in all 50 states. Some countries in Europe have banned CCA wood and its use is being reviewed by the whole European Union. It is incredible, but a single 12 foot 2 x 6 contains about 27 grams of Arsenic - enough arsenic to kill more than 200 adults. A tablespoon (about 20 grams) of CCA wood ash has enough arsenic to kill an adult human.To add to that, CCA wood ash tastes salty, and is a natural attractant to animals and livestock. 5 Tablespoons of this are enough to kill an 1100 pound cow, and this has already happened. Jim and Peggy Janson of Sauk Rapids, Minnesota had their dairy herd of 18 Holstein cows die after breaking down a neighbors' fence and eating salty CCA ash. State investigators determined that the cows found a pile of CCA wood ash which had been illegally dumped and they died from arsenic poisoning four days after ingestion of the ash: This Old House Magazine, Issue 17, March/April 1998, Page 118-125. This same effect could be expected on household pets and wildlife, such as deer. How does arsenic affect me?Arsenic can be inhaled or ingested, or, to a lesser degree, absorbed through the skin. One-tenth of a gram accumulated over a two month period can produce death, and arsenic is carcinogenic at much lower levels. The EPA limit in water is currently 50 ppb, and proposals to lower it to 2 ppb are in place.
Medical Effects of Arsenic from CCA ash: The Journal of the American Medical Association reported (Peters HA, et al: Seasonal exposure to arsenic from burning CCA treated wood. JAMA 251:(18)2393-96, 1984) on a Wisconsin family who burned CCA scraps in their home furnace for winter heating. Their hair fell out, all suffered severe, recurring nosebleeds, extreme fatigue and debilitating headaches. The parents complained about 'blacking out' for periods of several hours, followed by long periods of extreme disorientation. Both children suffered frequent seizures described as 'grand mal'. The symptoms were finally traced to breathing minute amounts of arsenic laden dust leaking from the furnace as fly ash. The family's houseplants and fish died, too, victims of copper poisoning from the same dust.
Toxic limits of ArsenicMedline references on ArsenicNational Institute of Health A series of references on Arsenic and public health: Medline Arsenic ReferencesEPA LimitsWater: EPA has set a limit of 0.001 ppm (10 ppb) of arsenic in drinking water: EPA LinksSoil: It has been reported that EPA has set a limits of 10 ppm (10 mg per kg) of arsenic in soil. Arsenic levels over this limit empower EPA to order an owner-funded cleanup of a commercial site. However; I have been unable to locate a hard citation to this figure. If anyone out there can find a reference from EPA on this, please let me know. Air: The Occupational Safety and Health Administration, OSHA, established a maximum permissible exposure limit for workplace airborne inorganic arsenic of 10 micrograms per cubic meter averaged over an eight-hour day.  Detection - Dosage MechanismWarning Signs: Both inorganic and organic Arsenic give no warning of its presence. arsenic compounds are white or colorless powders that have no specific taste or odor. Given the minute amount required to produce a lethal effect, the lack of a warning sign makes these very deadly substances.Presence: Inorganic arsenic is found in many kinds of rock, especially in ores that contain copper or lead. When these ores are smelted to extract the copper or lead, most of the arsenic is collected for pesticide. Like radiation, everyone is exposed to low levels of arsenic (especially inorganic arsenic) because very low levels of it are always present in soil, water, food and air. The average person ingests about 8 micrograms (about 8/1000 of a gram) in food every day. Arsenic is also present in cigarette smoke where it originates from insecticides on tobacco. Uptake Mechanisms: Arsenic can be taken in by ingestion, aspiration by breathing dust, and, to a much lesser degree, by absorption through the skin. Accidental poisoning has been reported to occur from wearing inadequate clothing when applying arsenic-based products. A lethal dose of Arsenic can also be achieved by a cumulative process over two months. Multiple sub-lethal doses received over a period of several weeks can accumulate in the body to achieve a lethal dose. And at very small doses, arsenic is carcinogenic.
Arsenic Toxicity:First, here is a terrific link about arsenic, toxicity and water treatment from Dartmouth University .The acute lethal dose of inorganic arsenic to humans has been estimated to be about 0.6 mg/kg/day: This means that for a 70 kg (150 pound) adult, a toxic dose is 42 mg or 0.042 grams. For a 20 pound child, this works out to 6 mg or 0.006 grams. For comparison, a 12 foot long 2x6 contains about 27 grams (or 27,000 mg) of arsenic, enough to kill more than 200 adults. Exposure to high levels of inorganic arsenic - greater than 100 ppm parts of arsenic in food or water - can also be fatal. Arsenic and arsenic compounds are known cancer-causing agents and have been implicated in lung and skin cancer and associated with birth defects. While organic arsenic (arsenic combined with carbon compounds) is less toxic it causes similar effects. More detailed toxicity information for the medical community can be found at: Risk Assessment Information Arsine Gas: Arsine gas (AsH3), is produced when elemental or inorganic arsenic reacts with zinc compounds or certain fungi. Arsine gas has been used as a nerve gas weapon, and is made by reacting zinc and arsenic in the presence of an acid. Building a deck using galvanized nails in an area of acid rain could theoretically cause this reaction, although the volume of Arsine gas would be expected to be low. Storing CCA wood ash in a galvanized bucket may be asking for trouble, however. Even at concentrations as low as 3-10 ppm, Arsine gas can cause toxic effects in a few hours RAIS data . Where Arsine gas is encountered at very low levels the onset of illness is slow and insidious. After a period of months, cumulative hemolytic effects present as resting dyspnea (breathlessness), severe exercise intolerance and a tachycardia (rapid pulse rate). These signs may be coupled with vague neurological symptoms with a strange feeling in the legs. Hypoxia resulting from exposure to low levels of Arsine gas can lead to blackouts of varying duration. At this stage removing the source of contact with Arsine gas may not help, because of the 'latency period' of one to six months in the development of neurological symptoms. Recovery from the hemolytic effects leads to a compensatory condition 'polycythemia' an excess of red blood cells, in patients with normal RBC metabolism. Lengthy low-level exposure to arsine gas leads to a third stage of the illness which has similarities to the onset of acute arsine gas poisoning, including brown urine, dizziness, headache and delirium. This is followed by progressive paralysis of the legs and arms leading to 'foot drop', 'wrist drop', 'ataxia' and generalized symptoms including problems with 'proprioception' or position sense. Recovery from sub-lethal arsine exposure is slow: six months of variable paralysis followed by a recovery time of two to four years. Depending on exposure, there is a possibility of permanent nerve damage affecting the extremities, particularly the hands and fingers. The effects of arsine gas on infants and the fetus are not well documented, but there is some anecdotal evidence. In the late 1950s the New Zealand military, treated bedding and sheep skins used for crib pads with an arsenic compound as a fungicide (Arsenic is still used as the fungicide in CCA wood). However, a fungus called 'Scopulariopsis breviculis' can metabolize arsenic and emits arsine gas as a by product. Arsine gas may have been responsible for a high rate of infant mortality from sudden infant death syndrome (SIDS) at that time in New Zealand. Cot death or SIDS was abnormally high in military families where arsenic was used as a fungicide in 'Official Issue' bedding. A prestigious institution of clock makers has circulated a warning to its members that in the renovation of old clocks there is a danger of Arsine gas poisoning due to the pigment 'Scheeles Green' used in fret screens. The same fungus 'Scopulariopsis breviculis' mentioned above was responsible for the 'Wallpaper and paste' poisonings of the 19th century in Europe. Arsenic used as a fungicide in wallpaper was metabolized by the fungus and Arsine gas released. The question for us is, will this fungus attack CCA Pressure-Treated Wood?. Information on Arsine Gas courtesy of Brian Shadd, Diagnostic engineers, UK
Signs of Arsenic PoisoningEffects of mild poisoning from inhalation include loss of appetite, nausea, and diarrhea. Effects of more severe exposure to arsenic include (1) 'pins and needles' tingling in the palms, or cramps in calf muscles (2) Heat and irritation in throat and stomach, a garlic odor on breath, or a metallic taste in the mouth (3) vomiting, purging with very loose stools (4) neurological effects including restlessness, chronic headaches, apathy, fainting, dizziness, delirium, somnolence, convulsions or coma.Signs of long-term exposure include (1) development of white crescent-moon marks on the fingernails (2) a darkening of the skin, skin lesions, a skin rash and the appearance of small warts on the palms, soles and torso, mottled spotting of the skin pigmentation, looking like 'raindrops on a dusty road'.
TreatmentArsenic is cleared from the body quickly, so the most important remedy for arsenic poisoning is eliminating exposure. The most serious effects of arsenic, such as cancer and diabetes, are believed to require long, continuous exposures perhaps lasting 20 years or more.Immediate Acute arsenic Poising: Subjects with suspected arsenic poisoning should always be directed to immediate medical care. There are no actual antidotes to immediate arsenic poising, and the best that can be done immediately after ingestion is to cause the subject to vomit immediately after ingestion. Lavage or emetics--apomorphine, zinc sulfate, mustard, ipecac, magnesia, even burnt toast, should be continued under a doctors' supervision at intervals for up to two days, then castor oil. IV fluids will likely be necessary to prevent the subject from dehydrating. Subjects with suspected arsenic poisoning should always be directed to immediate medical care. Once arsenic has been ingested, the best treatment may be to introduce agents to bind to the arsenic and help prevent its toxic effects. Because arsenic binds strongly to sulfur, sulfur based compounds and chelating agents have shown good success. Chelating agents such as "British anti-lewisite" (BAL) work by binding arsenic tightly in complexes, making it inactive. This can help deactivate arsenic and remove it from a person's body, averting severe toxicity and death. Chelating agents bind tightly to metals like arsenic and mercury, and can help in eliminating these from the system. See information on Chelation treatment from a clinic in Atlanta, and on specific chelation agents from S.E.R.B labs, a pharmaceutical company in France. For more information about the toxicity of arsenic, contact: Mike Kamrin Agency for Toxic Substances and Diseases Registry 1. This Old House Magazine, Issue 17, March/April 1998, Page 118-125
It is our intention to have this a completely factual forum for the discussion of the risks and benefits of CCA and other pressure treated woods. If you would like to contribute, correct errors, have an idea, gripe, link or comment, contact me, Richard Martin . I want to make this a balanced public forum, and as factual as possible. I would be happy to add your comments or counterpoint to our comment page.
Liability: This site is intended as a discussion site only to present only factual information about arsenic and its effects on the environment. This site is not intended to either promote or denigrate any product over any another. The Author assumes no liability beyond the liability to correct material facts in error.
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