Copper chromium arsenic preservative

A copper chromium arsenic preservative is used in industrial pretreatment of timber. This process creates the potential for operator exposure (Garrod etal. 1999) as well as the need to remediate soil contaminated with the preservative (Balasoiu etal. 2001). Potentially, further remediation is needed when the wood might be recycled for wood chips (Velizarova et al. 2002). 

Yeates, G.W., V.A. Orchard, T.W. Speir, J.L. Hunt, andM.C.C. Hermans. 1994. Impact of pasture contamination by copper, chromium, arsenic timber preservative on soil biological activity. Biol. Fertil. Soils 18 200-208. 

McCarthy and coworkers (74) at the Australian Forest Products Laboratory reported that a pressure treatment for pine posts with zinc-copper-chromium-arsenic-phosphorus preservative produced a leach-resistant treatment having both fire retardancy and preservation against decay. This treatment system is reported to have commercial application in Australia. 

Metals are major pollutants only at wood preserving plants that treat with water-borne salts of copper, chromium, arsenic, and zinc. 

British Standard 5666, Methods of Analysis of Wood Preservatives and Treated Timber, Part 3, Quantitative Analysis of Preservatives and Treated Timber Containing Copper, Chromium, Arsenic Formulations, British Standards Institution, 2 Park Street, London W1A 2BS, 1979. 

Many of the biocides presently used in wood preservation preparations, e.g. pentachlorophenol (PCP), linane (y-HCH), creosote, and copper chromium arsenic-salts... 

McCarthy et al. (97) tested a zinc, copper, chromium, arsenic, phosphorus preservative on fence posts. The addition of the zinc and phosphorus eliminated the afterglow problem caused by this treatment. However, incorporation of the phosphorus reduced the effectiveness of the decay resistance. 

Copper chromium arsenate as a wood preservative Calcium and sodium arsenate herbicides Lead arsenate formerly used on fruit crops Formerly in cotton defoliants Sodium arsenite in cattle and sheep dips Alloys with copper and lead for bearings With aluminum, gallium, and indium in semiconductors... 

Early insecticides were often inorganic arsenic, copper, lead, and sulfur compounds.6 An example is Bordeaux mixture, which contains copper sulfate and calcium hydroxide. Copper chromium arsenate is used today as a wood preservative. Organic natural products, such as pyrethrin and rotenone (11.1) have also been used. Rotenone is used today for killing undesirable fish, such as carp, before restocking ponds with game fish. Many synthetic pyrethrins are used today because of their relative safety to humans. However, both rotenone and pyrethrin7... 

It is possible that this or a similar compound could be used to replace the copper-chromium arsenate treatment now used on wood. Carvacrol is fairly volatile, bp 237°C. It would be interesting to see how fast it would be released from wood treated with it under pressure. If it is released too fast for purposes of preservation, the wood could be im-... 

Inorganic compounds of the copper, chromium, arsenic (CCA) type C for preservation of wood used in industrial installations using vacuum or pressure to impregnate wood (condition wood so treated may not be placed on the market before fixation of the preservative is completed). 

Wood poles typically require treatment with preservatives [e.g., creosote, copper chromium arsenate (CCA), penta-chloro-phenol (Penta)] to resist rot, decay, etc., in order to yield a service life of about 30-35 years. Due to preservation treatments of wood poles [22] which are hazardous to humans, the US-EPA regulations have led to evaluating the viability of alternatives to treated wood poles, i.e., steel, concrete, and FRP composite. Recently, through a strong push from the American Composites Manufacturers Association (ACMA), FRP composite poles have been receiving greater attention from electrical utility and telecommunication companies due to their inherent advantages over poles made of conventional materials. 

Durability of wood and wood-based products. Performance of preventive wood preservatives as determined by biological tests. Part 1. Specification according to hazard class Methods of analysis of wood preservatives and treated timber. Part 3. Quantitative analysis of preservatives and treated timber containing copper/chromium/arsenic formulations Specification for wood preservation by means of copper/chrome/arsenic compositions Standards for waterborne preservatives... 

Zinc in contact with wood Zinc is not generally affected by contact with seasoned wood, but oak and, more particularly, western red cedar can prove corrosive, and waters from these timbers should not drain onto zinc surfaces. Exudations from knots in unseasoned soft woods can also affect zinc while the timber is drying out. Care should be exercised when using zinc or galvanised steel in contact with preservative or fire-retardant-treated timber. Solvent-based preservatives are normally not corrosive to zinc but water-based preservatives, such as salt formulated copper-chrome-arsenic (CCA), can accelerate the rate of corrosion of zinc under moist conditions. Such preservatives are formulated from copper sulphate and sodium dichromate and when the copper chromium and arsenic are absorbed into the timber sodium sulphate remains free and under moist conditions provides an electrolyte for corrosion of the zinc. Flame retardants are frequently based on halogens which are hygroscopic and can be aggressive to zinc (see also Section 18.10). 

Kazi, E.K.M. and Cooper, P.A. (2002). Rapid extraction oxidation process to recover and reuse copper chromium and arsenic from industrial wood preservative sludge. Waste Management, 22(3), 293-301. 

At older production facilities or places where wastes have been disposed off-site, the creosote materials are often mixed with other chemicals. For instance, pentachlorophenol (PCP) is commonly encountered at NPL sites involved with wood-preserving operations along with such metals as copper, chromium, and arsenic (Davis et al. 1993 Kuehl et al. 1990 Mueller et al. 1989, 1991). At many of these sites, PAHs from combustion sources other than coal tar may have been introduced. The wastes from old town-gas sites may contain benzene, toluene, ethylenebenzene, or xylenes, and sometimes cyanides (Arvin and Flyvbjerg 1992 EPA 1987b Flyvbjcrg etal. 1993). 

Copper, chromium, and arsenic may be leached from wooden structures such as wharves preserved by chromated copper arsenate (CCA). CCA is toxic to aquatic biota in laboratory tests. In the field the effects are limited to a few meters in the vicinity of the preserved structures [91]. 

A mixture of chromium, copper, and arsenic (known as CCA) has been used for many decades as a wood preservative you can usually tell if wood has been treated by CCA as it will have a light-greenish tint. The use of CCA as a preservative is slowly being phased-out, however, due to concerns that acidic environments (such as acid rain, for example) could cause the arsenic to leach out of the wood and into the environment. 

Lambert M (1969) The determination of copper, chromium and arsenic in preservative treated timber by the method of atomic absorption spectrophotometry. Journal of the Institute of Wood Science 4 27-36. 

Wood Preservation. The use of chromium compounds ia wood preservation is largely because of the excellent results achieved by chromated copper arsenate (CCA), available ia three modifications under a variety of trade names. The treated wood (qv) is free from bleeding, has an attractive ohve-green color, and is paintable. CCA is widely used, especially ia treating utility poles, bull ding lumber, and wood foundations. About 62% of all the chromic acid produced ia the United States is consumed by the wood preservation industry (77,167) (see Building materials, survey). 

Imagine that a friend has asked you to review the title and abstract of a paper that is being written with other researchers on chromated copper arsenate (CCA), a compound used to preserve wood. The research team examined the chemical structure of arsenic (As) and chromium (Cr) in CCA to determine if the oxidation state of As and Cr changed over time due to weathering. 

At the Coast Wood Preserving, Inc., Superfund site (Ukiah, California), the technology was used to remove metal contamination to comply with both state and federal cleanup standards [50 parts per billion (ppb) arsenic, 50 ppb chromium, and 1 ppm copper]. The estimated total cost for the source control component of the remedy was 1,000,000, and the estimated total operational and maintenance costs was estimated to be 19,500 for a 20-year period (D16888B, p. 3, Report Documentation p. 2). 

Chromium copper arsenate is a commonly used preservative for softwood. To a lesser extent, ammoniacal copper arsenate is also used. 

Wood preserved with Chromated Copper Arsenate (CCA), a chemical mixture consisting of three pesticidal compounds (arsenic, chromium and copper)... 

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