The composition of CCA products is usually described in terms of the mass percentages of chromium trioxide or "chromic acid" CrO3, arsenic pentoxide As2O5, and copper (II) oxide CuO. The preservative is applied as a water-based mixture containing 0.6–6.0% (by weight) of chromic acid, copper oxide, and arsenic acid (USDA, 1980), with pH 1.6–2.5.
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What is the CCA process for treated wood?
Feb 04, 2022 · Chromated arsenicals, which include chromated copper arsenate (CCA), are a group of pesticides containing chromium, copper, and/or arsenic that protect wood against termites, fungi and other pests that can degrade or threaten the integrity of wood products. Chromated arsenicals-treated wood is used to produce commercial wood poles, posts ...
What is CCA and how is it used?
The CCA process was pioneered in 1933 and is used worldwide. Copper and arsenic in the preservative protect the wood from insect and fungal attack. Chromium (chrome) ‘locks’ the copper and arsenic into the timber and reduces the risk of the chemicals leaching out. The CCA process gives the treated wood a green tint. Arsenic
Are CCA chemicals mobile in soil?
Chromated copper arsenate (CCA) is a chemical wood preservative containing chromium, copper and arsenic. CCA is used in pressure treated wood to protect wood from rotting due to insects and microbial agents. USEPA/OPPTS; Pesticides: Regulating Pesticides. Chromated Copper Arsenate (CCA) Case 0132.
Are there any alternatives to CCA treatments?
Oct 14, 2014 · Chromated Copper Arsenate (CCA) Wood Preservatives. Chromated copper arsenate (CCA) wood preservatives contain chromium, copper and arsenic. Pressure-treated wood containing CCA is no longer used in most residential settings. The chemicals in CCA-treated wood have been shown to leach into the surrounding environment and can transfer to the skin …
What is CCA made of?
What is CCA process?
What is CCA preservative?
What is CCA treatment?
What is a smaller proposer?
How long do the VOA have to respond to a challenge?
Is CCA still used?
What is the problem with CCA?
What is CCA plywood?
How long does CCA treatment last?
What is CCA H3 treated pine?
What does CCA smell like?
What is a CCA?
Chromated Arsenicals (CCA) Chromated arsenicals, which include chromated copper arsenate (CCA), are a group of pesticides containing chromium, copper, and/or arsenic that protect wood against termites, fungi and other pests that can degrade or threaten the integrity of wood products. Chromated arsenicals-treated wood is used to produce commercial ...
What is chromated copper arsenate?
Chromated arsenicals, which include chromated copper arsenate (CCA), are a group of pesticides containing chromium, copper, and/or arsenic that protect wood against termites, fungi and other pests that can degrade or threaten the integrity of wood products.
What is wood treated with?
Wood treated with other preservatives approved by EPA; Wood-alternative and composite materials (including steel, fiberglass-reinforced concrete, laminated wood); and. Species of wood that are resistant to pests.
What is the CCA process?
The CCA process was pioneered in 1933 and is used worldwide. Copper and arsenic in the preservative protect the wood from insect and fungal attack. Chromium (chrome) ‘locks’ the copper and arsenic into the timber and reduces the risk of the chemicals leaching out. The CCA process gives the treated wood a green tint.
What is CCA treated wood?
Copper chrome arsenate (CCA) treated timber is wood that has been treated with a preservative containing copper, chromium and arsenic. CCA treatment prolongs the life of the wood. This is why, in the past, CCA treated timber was commonly used in decking, playground equipment, fences, retaining walls, jetties and vineyards.
Can CCA treated wood be ingested?
The main concern with CCA-treated timber is that it contains arsenic, which can be ingested (swallowed) or inhaled (when CCA-treated timber is burnt). Over time, small amounts of chemicals may leach from CCA-treated timber, but research has found that the amount of leached arsenic is less than that found in common foods.
What is CCA treated timber used for?
CCA-treated timber can be used for poles, fencing, landscaping timbers, piling and other structure foundations, residential construction, industrial and commercial construction, rural and farm use, fresh and salt water structures, signage and boat construction.
Do you have to remove CCA treated timber?
Existing structures made from CCA-treated timbers do not need to be removed and replaced until they reach the end of their functional life. These recommendations have been made as a precaution since there is no evidence to suggest that CCA-treated timber is harmful when handled or used properly.
Can children eat arsenic?
Playground equipment. It has been proposed that children risk eating tiny amounts of arsenic from their hands after playing on CCA -treated timber play equipment or swallowing the soil surrounding the equipment. However, there is insufficient evidence to demonstrate that CCA-treated timber poses a health risk.
How to prevent splinters in wood?
Wear eye goggles, gloves and appropriate clothing to prevent splinters. Keep food and drinks away from sawdust or CCA-treated wood surfaces. Wash your hands and face after working with the wood, and before eating, drinking or any other activity that involves hand-to-mouth contact, such as smoking.
What is CCA treatment?
CCA treatment solutions are typically classified by the American Wood-Preservers' Association (AWPA) as either type A, B, or C, with CCA type C ( CCA-C) being the formulation most commonly used for pressure treating dimensional lumber for residential applications .
What is CCA in wood?
Chromium copper arsenate (CCA) was used for the protection of wood building materials until the restriction by EPA in 2002. During a short period of time 14-24hr, a comparative nephrotoxicity study was performed regarding the effects of CCA and its compounds per se. Histopathological and histochemical features were correlated with the concentration of the total arsenic and chromium in mice kidney. Animals were subcutaneously injected with CCA (7.2 mg/kg arsenic and 10.2mg/kg chromium per body weight), CrO3 (10.2 mg/kg), As2O5 (7.2 mg/kg) and NaCl (0.9%) per se. The histopathological examination of the renal sections evidenced acute tubular necrosis in the groups of animals exposed to CCA (in both periods of time). Although the same contents of pentavalent arsenic and hexavalent chromium were injected in treated animals with CCA and with the prepared solutions of As2O5 and CrO3, the arsenic concentration on kidneys of CCA-exposed animals was much higher than those in animals exposed to As2O5 (32- and 28-fold higher at 14 and 24 hr, respectively). However, the elimination of chromium seems to occur similarly in the kidneys of animals treated with CCA and CrO (3) per se. Interactions among the components of CCA result in a marked decrease of the ability of kidney to eliminate simultaneously both analytes. The nephrotoxicity of CCA was higher than its components per se, evidencing a possible synergetic effect.
What is chromated copper arsenate?
IDENTIFICATION AND USE: Chromated copper arsenate (CCA) is a chemical wood preservative containing chromium, copper and arsenic. CCA is used in pressure treated wood to protect wood from rotting due to insects and microbial agents. Effective December 31, 2003, no wood treater or manufacturer may treat wood with CCA for residential uses, with certain exceptions. HUMAN EXPOSURE: Itching, burning rashes, neurological symptoms, and breathing problems have been associated with handling unmarked chromated arsenical wood preservatives, including contact with the sap draining from wood treated with chromated arsenical wood preservatives. Two workers were exposed while working with CCA-treated wood. Symptoms reported included headache, nausea, shakiness, and thirst. In another case, pressure treated wood caused a chronic rash that persisted for three years. A 33-year-old man attempted suicide by ingesting an unknown liquid, later identified as a CCA wood preservative, 75 min before his arrival in the emergency department. He was in severe respiratory distress, drooling, tachycardic, and hypotensive. There was an orange color on the palms of both hands. He developed multiple premature atrial contractions and supraventricular tachycardia, and later in the intensive care unit, refractory ventricular tachycardia and ventricular fibrillation. The patient was declared dead 2.5 hr after his arrival. ANIMAL STUDIES: Exposure to chromium and arsenic induced significant modifications in the redox state of the kidney tissue in mice, evidenced by significant alterations in glutathione-s-transferases (GSTs) and glutathione peroxidase (GPx) activities. No alterations were found concerning the activity of catalase. Administration of CCA to mice produced acute tubular necrosis. The findings in mice suggest that CCA has sensitizing activity. In cows CCA poisoning produced diarrhea, weakness, stumbling, and sometimes death. ECOTOXICITY STUDIES: Field studies demonstrated that green algae growing on CCA Type C treated wood docks would accumulate copper, chromium and arsenic above levels in algae growing on rocks. CCA treatment resulted in an increased arsenic content of bees from those hives. CCA treatments of beehives were associated with winter losses of colonies.
Can you use bleach on CCA treated wood?
The use of bleaches, deck cleaners or brighteners that contain sodium hypochlorite, sodium hydroxide, sodium percarbonate, oxalic acid, or citric acid is not recommended as they may release toxic chemicals from CCA-treated wood.
How much CCA was used in 2002?
Based on EPA proprietary data and public literature, the Agency estimates that approximately 110 million pounds of CCA were used in 2002, although this number is likely less today based on the voluntary use changes implemented in 2003.
What are the symptoms of chromated arsenical wood?
/SIGNS AND SYMPTOMS/ Itching, burning rashes, neurological symptoms, and breathing problems have been associated with handling unmarked chromated arsenical wood preservatives, including contact with the sap draining from wood treated with chromated arsenical wood preservatives. Treated wood has been reported as a potential source of dermal and inhalation exposure leading to dermatitis and development of film on the teeth. "Ruined" nerves in feet and legs believed to be from saw dust and fumes from cutting and routing chromated arsenical wood preservatives treated lumber have also been reported. /Chromated arsenical wood preservatives/
What metals can be leached from treated wood?
TERRESTRIAL FATE: Field and laboratory studies have demonstrated that under certain circumstances copper, arsenic, and/or chromium can leach from treated wood into the surrounding soil or water (1). In general, most leaching takes place in the first few days and the extent and rate of leaching being highest for copper and lowest for chromium (1). Available field and laboratory studies suggest that leaching of metals is highly variable and is dependent on environmental conditions (1). In most cases, after migration of the metals a few meters down into soil, these metals attain the background level concentration of soil (1). Using a field study in Dartmoor, Victoria, Australia, it was shown that both the quantity of chromated copper arsenate added to a fine sandy loam soil (organic matter of about 1-2%) and the pH of irrigation water will influence chromated copper arsenate transport (2). This suggests the acidic rainfall or large accidental spillage will increase the risk of groundwater pollution (2). Adsorption of arsenic and copper is much greater than chromium (2). Chromium is released into water and soil as trivalent chromium, but the concentration of trivalent chromium is the lowest of the three metals, partly attributed to the fixation process in the wood structure (1). Arsenic is leached into soil and water as pentavalent arsenic (1). Because metals tend to attain background level concentrations in soil and water and because the metals tend to change forms (speciate), it is often difficult to identify the source (s) of the contamination in water and soil (1).
What are the chemicals in CCA wood?
Chromated copper arsenate (CCA) wood preservatives contain chromium, copper and arsenic. Pressure-treated wood containing CCA is no longer used in most residential settings. The chemicals in CCA-treated wood have been shown to leach into the surrounding environment and can transfer to the skin when people touch the wood. CCA residues on the skin typically result in minimal exposure. However, eating, smoking or children's hand-to-mouth activity can lead to ingestion of the chemicals. Long-term exposure to arsenic can increase the risk of cancer over a lifetime.
What is CCA wood?
Pressure-treated wood containing CCA is no longer used in most residential settings. The chemicals in CCA-treated wood have been shown to leach into the surrounding environment and can transfer to the skin when people touch the wood.
When did CCA stop being used?
Effective December 31, 2003, chromated arsenical manufacturers voluntarily canceled virtually all residential uses of CCA, and wood products treated with CCA are no longer used in most residential settings, including decks and children’s playsets.
What is ACQ wood?
ACQ (alkaline copper quaternary) is a water-based wood preservative that prevents decay from fungi and insects (i.e., it is a fungicide and insecticide). It also has relatively low risks, based on its components of copper oxide and quaternary ammonium compounds.
What is wood preservative?
Wood preservative products are those that control wood degradation problems due to fungal rot or decay, sapstain, molds, or wood-destroying insects. Both the treatment process and the use of treatedproducts can result in risks to human health and the environment. Treated wood is most commonly used outdoors.
Is triadimefon a wood preservative?
Triadimefon is a triazole fungicide that was first registered as a wood preservative in 2009. Triadimefon was approved by EPA for preserving wood-based composite products and wood products intended for above ground and in ground contact such as wood decking, patio furniture, millwork, guardrails, utility poles, foundation pilings, and fences.
What is the most common preservative used in wood?
Three chemicals in a class called isothiazolinones can be used as wood preservatives. The most common of these is DCOIT (3 (2H)-isothiazolone, 4,5-dichloro-2-octyl), which was first registered in 1996 as a wood preservative for use via pressure treatment, for sapstain protection, and in millwork applications.
What is creosote used for?
Creosote is obtained from high temperature distillation of coal tar. Pesticide products containing creosote as the active ingredient are used to protect wood against termites, fungi, mites and other pests that can degrade or threaten the integrity of wood products.
How is creosote obtained?
Creosote is obtained from high temperature distillation of coal tar. Pesticide products containing creosote as the active ingredient are used to protect wood against termites, fungi, mites and other pests that can degrade or threaten the integrity of wood products.
When was CCA introduced?
Still, Baeppler isn’t holding his breath. He points out that CCA was introduced in 1946 but wasn’t used to treat a majority of southern yellow pine poles until 2003. “We’re just on the cusp,” he says. “This is an industry that moves really, really slowly.”. Chemical & Engineering News. ISSN 0009-2347.
Is penta a carcinogen?
The US penta market, according to industry player Koppers, is worth about $40 million per year. But penta is also a possible carcinogen and is banned in most countries. This has prompted the sole North American producer to announce it will close its plant, in Mexico, by the end of 2021.
Do utility poles need preservatives?
They even serve as a superhighway for squirrels and a medium for posting yard sale signs. In order to last for decades after they are sunk into the ground, wood utility poles need preservatives that fend off termites, fungi, and the elements. Not many chemicals are up to the challenge.
What are the preservatives used in wood?
Preservatives are applied to wood under pressure in a treatment chamber. Easier-to-treat woods, like southern yellow pine, can be processed with waterborne preservatives such as chromated copper arsenate (CCA), which more than a decade ago was phased out of decking and other domestic lumber uses.
Where is Penta made?
The only North American producer of penta is Cabot Microelectronics Corporation (CMC), at a plant in Matamoros, Mexico. The penta operation tagged along as part of CMC’s 2018 purchase of KMG Chemicals, which was mainly a maker of materials for the electronics industry. It was hardly a core business for CMC.
Where is Gulbrandsen located?
Seeing a void it might fill, the privately owned chemical maker Gulbrandsen announced in January that it would build a penta plant at its facility in Orangeburg, South Carolina.
Is creosote a chemical?
Creosote, which is a mixture of many chemicals, does pose exposure risks. It is up to utility pole makers and their chemical suppliers to guess where the market will go. Koppers, number 2 in utility pole fabrication, behind Stella-Jones, produces wood preservatives such as creosote—used mostly on railroad ties—and copper-based chemicals.
Overview
Chromated copper arsenate (CCA) is a wood preservative containing compounds of chromium, copper, and arsenic, in various proportions. It is used to impregnate timber and other wood products, especially those intended for outdoor use, in order to protect them from attack by microbes and insects. Like other copper-based wood preservatives, it imparts a greenish tint to treated timber.
Composition and application
The composition of CCA products is usually described in terms of the mass percentages of chromium trioxide or "chromic acid" CrO3, arsenic pentoxide As2O5, and copper(II) oxide CuO.
The preservative is applied as a water-based mixture containing 0.6–6.0% (by weight) of chromic acid, copper oxide, and arsenic acid (USDA, 1980), with pH 1.6–2.5. The mixture is infused into wood at high pressure.
Mechanism of action
The chromium acts as a chemical fixing agent and has little or no preserving properties; it helps the other chemicals to fix in the timber, binding them through chemical complexes to the wood's cellulose and lignin. The copper acts primarily to protect the wood against decay, fungi, and bacteria, while the arsenic is the main insecticidal component, providing protection from wood-attacking insects including termites and marine borers. It also improves the weather resistance …
Alternatives
Alternative heavy-duty preservatives include creosote and pentachlorophenol. Similar water-borne preservatives include alkaline copper quaternary (ACQ) compounds, copper azole(CuAz), ammoniacal copper zinc arsenate (ACZA), copper citrate, and copper HDO (CuHDO). Usually more expensive options, but safer, are pressure and heat treated lumber which contains no chemicals. Usually they lack the long-term robust qualities and resistance of chemically treated lumber. So…
Safety
Concerns over the safety of CCA have focused on its chromium and arsenic contents.
Arsenic is found naturally in the soil, food and water, and is still used to treat some medical conditions However it has a long list of negative health effects, especially in inorganic form, by contact or by ingestion, and was designated a human carcinogen by the U.S. Environmental Protection Agency(EPA) in 1986 (even though its actual risk remains unclear). Arsenic in drinkin…
See also
• Timber treatment
• Paris Green
• Scheele's Green
• National Pesticide Information Center
External links
• National Pesticide Information Center - Chromated Copper Arsenate (CCA): Guide to selected resources
• Case Studies in Environmental Medicine - Arsenic Toxicity
• Case Studies in Environmental Medicine - Chromium Toxicity