Статті в журналах: "CCA wood"

1

Kim, J. J., S. M. Kang, Y. S. Choi, and G. H. Kim. "Microfungi potentially disfiguring CCA-treated wood." International Biodeterioration & Biodegradation 60, no. 3 (January 2007): 197–201. http://dx.doi.org/10.1016/j.ibiod.2007.05.002.

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2

Yildiz, Sibel, Sabriye Canakci, Umit C. Yildiz, Ozlem Ozgenc, and Eylem D. Tomak. "Improving of the impregnability of refractory spruce wood by Bacillus licheniformis pretreatment." BioResources 7, no. 1 (December 2, 2011): 565–77. http://dx.doi.org/10.15376/biores.7.1.565-577.

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In this study it was aimed to improve impregnability of spruce (Picea orientalis L.) wood with bacteria (Bacillus licheniformis A1) pretreatment, using copper/chromium/arsenic Type C (CCA-C) andcopper azole Type A (CBA-A). The effects of Bacillus licheniformis A1 on weight loss, copper uptake, and compression strength of samples were determined. Weight loss was slightly changed by bacterial degradation in all test groups. The best copper uptake cases were 1466 ppm for CCA-C and 2730 ppm for CBA-A. Improvement on copper uptake with bacteria pretreatment was in a range of 18 to 103% compared to control samples. Compression strength was decreased by bacterial degradation. However strength losses might be acceptable for several construction applications. Bacillus licheniformis A1seems to havea good potential for increasing the permeability of spruce wood.

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3

Xing, Dan, Ahmed Koubaa, Yubo Tao, Sara Magdouli, Peng Li, Hassine Bouafif, and Jingfa Zhang. "Copper-Doped Carbon Nanodots with Superior Photocatalysis, Directly Obtained from Chromium-Copper-Arsenic-Treated Wood Waste." Polymers 15, no. 1 (December 28, 2022): 136. http://dx.doi.org/10.3390/polym15010136.

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An ecofriendly approach was developed for preparing copper-doped carbon dots (CDs) with superior photocatalysis using chromium-copper-arsenic (CCA)-treated wood waste as a precursor. Original wood (W-CDs), CCA-treated wood (C-CDs), and bioremediation CCA wood (Y-CDs) were used as the precursors. The chemical composition and structural, morphological, and optical properties, as well as the photocatalytic ability of the synthesized CDs varied with wood type. The C-CDs and W-CDs had similar characteristics: quasispherical in shape and with a diameter of 2 to 4.5 nm. However, the Y-CDs particles were irregular and stacked together, with a size of 1.5–3 nm. The presence of nitrogen prevented the formation of an aromatic structure for those CDs fabricated from bioremediation CCA wood. The three synthesized CDs showed a broad absorption peak at 260 nm and a weak absorption peak at 320 nm. Proof of the model study for the fabrication of luminescent CDs from CCA wood waste for bioimaging was provided. The degradation rate of CD photocatalytic MB was 97.8% for 30 min. Copper doping gives the CDs electron acceptor properties, improving their photocatalytic efficiency. This study provides novel ways to prepare nanomaterials from decommissioned wood as a nontoxic and low-cost alternative to fluorescent dots.

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4

ALTANER, CLEMENS. "PRESERVATIVE TREATED TIMBER PRODUCTS IN NEW ZEALAND." Cellulose Chemistry and Technology 56, no. 7-8 (September 28, 2022): 705–16. http://dx.doi.org/10.35812/cellulosechemtechnol.2022.56.62.

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Copper Chrome Arsenic (CCA) is a potent wood preservative. It is currently the dominant wood preservative used in Aotearoa (New Zealand). Internationally, CCA has been phased out in many jurisdictions over the last decades due to health and environmental concerns. This review summarises the current knowledge about the health and environmental risks of CCA treated timber, revisits the risk assessment of New Zealand authorities of CCA treated timber and discusses the challenges New Zealand is facing from the continued use of this product. Overall, the attitude towards CCA treated timber is changing, with local government bodies and agricultural industries facing increasing challenges around the disposal of CCA treated timber and site remediation from CCA leaching.

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5

Donovan, Geoffrey, and Hayley Hesseln. "Consumer Willingness to Pay for a Naturally Decay-Resistant Wood Product." Western Journal of Applied Forestry 19, no. 3 (July 1, 2004): 160–64. http://dx.doi.org/10.1093/wjaf/19.3.160.

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Abstract Chromated copper arsenate (CCA) is the most widely used chemical wood preservative in the United States. Concerns about the safety of CCA led to an agreement between the Environmental Protection Agency and the wood treatment industry to withdraw CCA for nonindustrial uses by the end of 2003. In light of the publicity surrounding the withdrawal of CCA, this article evaluates consumers' willingness to pay a premium for products manufactured from naturally decay-resistant wood as opposed to chemically treated wood. We use a national contingent valuation survey to quantify consumer willingness to pay for a children's play structure made from Alaska yellow-cedar, as opposed to an identical play structure made from southern pine treated with ammonial copper quaternary, the likely replacement for CCA. Respondents' estimated mean willingness to pay for the Alaska yellow-cedar play structure is $2,013, compared to $1,000 for the treated southern pine structure. This study shows that manufacturers of products made from naturally decay-resistant wood may be able to capture a substantial premium for their products. West. J. Appl. For. 19(3):160–164.

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6

CHIBA, KEIKO, SHINPEI UCHIDA, YOSHINORI HONMA, KOICHIRO SERA, and KATSUMI SAITOH. "EXTANT CONTENTS OF CHROMIUM, COPPER AND ARSENIC IN WASTE CCA-TREATED TIMBER." International Journal of PIXE 19, no. 01n02 (January 2009): 103–9. http://dx.doi.org/10.1142/s0129083509001795.

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The segregation and disposal of chromated copper arsenate ( CCA )-treated wood waste when recycling building waste materials is a serious issue. We examined the contents of CCA preserved cedar timber by PIXE analysis. CCA preserved timber contained large amounts of these metals both on the surface and core of the wood. The ratio of chromium, copper and arsenic contained on the surface was 1:2:1, and in contrast, the ratio in the core was 1:1:2. In other words, the arsenic content was highest in the core. Moreover, the chemical form of arsenic in both parts of the wood was only inorganic arsenic; the same form of arsenic in preservative components known as carcinogenic substances. These findings mean that the complete separation of waste CCA preserved timber from construction and demolition wood is needed.

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7

Fu, Qirong, Dimitris S. Argyropoulos, David C. Tilotta, and Lucian A. Lucia. "Understanding the pyrolysis of CCA-treated wood." Journal of Analytical and Applied Pyrolysis 81, no. 1 (January 2008): 60–64. http://dx.doi.org/10.1016/j.jaap.2007.08.003.

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8

Fu, Qirong, Dimitris S. Argyropoulos, David C. Tilotta, and Lucian A. Lucia. "Understanding the pyrolysis of CCA-treated wood." Journal of Analytical and Applied Pyrolysis 82, no. 1 (May 2008): 140–44. http://dx.doi.org/10.1016/j.jaap.2008.02.007.

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9

Nakai, Satoshi, Koujiro Kawakami, Tetsuji Okuda, Wataru Nishijima, Mitsumasa Okada, Toshiyuki Ohta, and Naoki Kumamoto. "Recycling of CCA-Treated Wood as Pulp." KAGAKU KOGAKU RONBUNSHU 36, no. 4 (2010): 304–9. http://dx.doi.org/10.1252/kakoronbunshu.36.304.

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10

Townsend, Timothy, Brajesh Dubey, Thabet Tolaymat, and Helena Solo-Gabriele. "Preservative leaching from weathered CCA-treated wood." Journal of Environmental Management 75, no. 2 (April 2005): 105–13. http://dx.doi.org/10.1016/j.jenvman.2004.11.009.

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11

Waldron, Levi, Paul A. Cooper, and Tony Y. Ung. "Prediction of long-term leaching potential of preservative-treated wood by diffusion modeling." Holzforschung 59, no. 5 (September 1, 2005): 581–88. http://dx.doi.org/10.1515/hf.2005.095.

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Abstract An approach to modeling leaching and leaching impacts of preservative components from treated wood is presented based on three simple laboratory determinations: the amount of preservative component available for leaching (Le), equilibrium dissociation of preservative into free water in wood (Di) and diffusion coefficients for component leaching in different wood directions (D). In this study, the following inorganic wood preservative systems were investigated: chromated copper arsenate (CCA), the copper component of copper azole (CA) and alkaline copper quaternary (ACQ), and boron in disodium octaborate tetrahydrate (DOT). Aggressive leaching of finely ground wood showed that amounts of preservative compounds available for leaching were highest for borates, followed by copper in copper amine systems and arsenic in CCA, copper in CCA and chromium in CCA. The equilibrium dissociation or solubility of components in free water in the wood was much higher for borates and copper amine, followed by copper and arsenic in CCA and chromium in CCA. Use of the applicable diffusion coefficient (D) and Di or Le values in a diffusion model allows the prediction of total amount leached and emission or flux rate at different times of exposure for products with different dimensions and geometries. The approach was tested and generally validated through application of the model to results of laboratory water spray leaching of full-size lumber samples. The approach explains the rapid leaching of boron compounds (large diffusion coefficient and high initial dissociated concentration) compared to other preservative components and predicts that ACQ will have higher initial leaching rates compared to CCA and CA, but the latter preservatives will continue to leach copper at a measurable rate for a much longer time. The practical implications and limitations of the approach are discussed.

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12

Morais, Simone, Henrique M. A. C. Fonseca, Sónia M. R. Oliveira, Helena Oliveira, Vivek Kumar Gupta, Bechan Sharma, and Maria de Lourdes Pereira. "Environmental and Health Hazards of Chromated Copper Arsenate-Treated Wood: A Review." International Journal of Environmental Research and Public Health 18, no. 11 (May 21, 2021): 5518. http://dx.doi.org/10.3390/ijerph18115518.

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Copper chrome arsenate (CCA) water-borne solution used to be widely used to make timber highly resistant to pests and fungi, in particular, wood products designed for outdoor use. Nowadays, CCA is a restricted chemical product in most countries, since potential environmental and health risks were reported due to dermal contact with CCA residues from treated structures and the surrounding soil, as well as the contamination of soils. However, large quantities of CCA-treated timber are still in use in framings, outdoor playground equipment, landscaping, building poles, jetty piles, and fencing structures around the world, thus CCA remains a source of pollutants to the environment and of increasing toxic metal/metalloid exposure (mainly in children). International efforts have been dedicated to the treatment of materials impregnated with CCA, however not only does some reuse of CCA-treated timber still occur, but also existing structures are leaking the toxic compounds into the environment, with impacts on the environment and animal and human health. This study highlights CCA mechanisms and the documented consequences in vivo of its exposure, as well as the adverse environmental and health impacts.

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13

Scouse, Adam A., Steven S. Kelley, Richard A. Venditti, and T. Eric McConnell. "Evaluating sustainable product alternatives by combining life cycle assessment with full-cost accounting: A highway guardrail case study." BioResources 15, no. 4 (October 16, 2020): 9103–27. http://dx.doi.org/10.15376/biores.15.4.9103-9127.

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Full-cost accounting techniques incorporate the environmental and societal burdens a product generates through its manufacture, use, and disposal into that product’s price. This research generates full-cost prices for functionally equivalent chromated copper arsenate (CCA) treated wood and galvanized steel guardrail posts by combining previously conducted life cycle inventory analyses results with secondary emission valuation data. Based on the analysis, both CCA-treated posts and galvanized steel posts have environmental damage costs associated with emissions generated through the product’s manufacturing, use, and disposal stages. After developing full-cost prices for product alternatives, CCA-treated wood guardrail posts were found to be a more economical and environmentally responsible alternative to galvanized steel. In addition to generating full-cost prices, this research uses Monte Carlo simulation to provide estimates of variability around CCA-treated wood and galvanized steel damage costs.

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14

Singh, Adya P. "The ultrastructure of the attack of Pinus radiata mild compression wood by erosion and tunnelling bacteria." Canadian Journal of Botany 75, no. 7 (July 1, 1997): 1095–102. http://dx.doi.org/10.1139/b97-120.

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An inspection of 12-year-old, copper–chrome–arsenate (CCA) treated Pinus radiata wood from an industrial cooling tower showed extensive surface decay of wood. Electron microscopic examination of decaying mild compression wood indicated that compression wood cells were attacked exclusively by bacteria, which were of erosion and tunnelling types. The highly lignified outer S2 wall and the middle lamellae in the compression wood tracheids were resistant to erosion bacteria, and were only occasionally attacked by tunnelling bacteria. These observations are discussed in relation to the information available on the structure and chemical composition of compression wood. Key words: compression wood, bacterial attacks, CCA-treated wood, Pinus radiata wood, erosion bacteria, tunnelling bacteria.

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15

FERRARINI, Suzana Frighetto, Luciana Gampert MIRANDA, Sandra Maria MAIA, and Marçal PIRES. "CHROMATED COPPER ARSENATE (CCA) TREATED WOOD: DESTINATION OPTIONS FOR WASTES GENERATED AND PERSPECTIVES IN THE DEVELOPMENT OF METHODOLOGIES FOR TOXIC ELEMENTS REMOVAL." Periódico Tchê Química 12, no. 23 (January 20, 2015): 7–21. http://dx.doi.org/10.52571/ptq.v12.n23.2015.7_p_23_pgs_7_21.pdf.

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The wood has been used for various functions, one of them is the manufacture of poles for electrification and telephony. However, this material has a big propensity to deteriorate. To increase its durability, some alternatives are employed, one of them is the incorporation of toxic substances (preservatives) to protect the wood from agents such as fungi, bacteria and xylophagous insects that cause its decay. Currently, the preservative chromated copper arsenate (CCA) is the most widely used for this purpose. However, when the CCA treated wood poles reach the end of their useful life, they become hazardous waste due to the presence of chromium and arsenic. In this work are presented the main methodologies for treatment, destination options and adequate disposal of these wastes, as well as different methods for toxic elements removal from the CCA-treated wood.

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16

Moskal, T. M., and D. W. Hahn. "On-Line Sorting of Wood Treated with Chromated Copper Arsenate Using Laser-Induced Breakdown Spectroscopy." Applied Spectroscopy 56, no. 10 (October 2002): 1337–44. http://dx.doi.org/10.1366/000370202760355316.

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This paper details the design, implementation, and field evaluation of an online detector system using laser-induced breakdown spectroscopy (LIBS) for the analysis of copper chromated arsenate (CCA) treated wood products. The LIBS-based instrument functioned by creating the laser-induced plasma directly on the sample surface while wood was translated under the detector system, and was successful in discriminating between CCA treated wood and untreated wood products based on the atomic emission signal of chromium. The system was optimized for plasma emission collection both in and out of the laser focal plane and temporally optimized for chromium analysis using a compact, non-intensified charge-coupled device (CCD)/spectrometer unit. Using either single laser pulse spectra or 5-shot and 10-shot spectral averages, the accuracy of LIBS-based analysis ranged from 92 to 100% for identifying both CCA treated and untreated wood samples from the waste stream at a construction and demolition debris recycling center. Additional implementation issues are discussed in the context of LIBS-based on-line sorting of construction and demolition wood debris.

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17

Singh, A. P., M. E. Hedley, D. R. Page, C. S. Han, and K. Atisongkroh. "Microbial Degradation of Cca-Treated Cooling Tower Timbers." IAWA Journal 13, no. 2 (1992): 215–31. http://dx.doi.org/10.1163/22941932-90001271.

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Transmission electron microscopy of decaying CCA-treated Pinus radiata timbers from an industrial water cooling tower showed the presence of a thick biofilm covering some areas of the wood. The biofilm contained various morphologically distinct forms of microorganisms embedded in a slime. The study provided evidence of the activity of soft rot fungi and tunnelling and erosion bacteria in wood cells covered by the biofilm. The extent of microbial damage to wood cells varied, with combined fungal and bacterial attack having the most damaging impact.

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18

Piao, Cheng, Charles J. Monlezun, Chung Y. Hse, and W. Allen Nipper. "Glue-Line Bonding Performance of Decommissioned CCA-Treated Wood. Part II: Retreated with CCA." Forest Products Journal 59, no. 10 (October 2009): 31–39. http://dx.doi.org/10.13073/0015-7473-59.10.31.

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19

SONOBE, Hozumi, Hideo ISHIDA, and Mitsuru AMANO. "Fixation Method of CCA-Treated Wood by Steaming." Wood Preservation 17, no. 5 (1991): 215–23. http://dx.doi.org/10.5990/jwpa.17.215.

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20

Hay, Emile, Hashmonai Derazon, Yosef Eisenberg, and Bukish Natalia. "Suicide by ingestion of a CCA wood preservative." Journal of Emergency Medicine 19, no. 2 (August 2000): 159–63. http://dx.doi.org/10.1016/s0736-4679(00)00202-x.

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21

Jacobi, Gary, Helena Solo-Gabriele, Timothy Townsend, and Brajesh Dubey. "Evaluation of methods for sorting CCA-treated wood." Waste Management 27, no. 11 (January 2007): 1617–25. http://dx.doi.org/10.1016/j.wasman.2006.09.014.

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22

Quintilhan, Manolo Trindade, Weslley Candido de Oliveira, Aylson Costa Oliveira, Bárbara Luísa Corradi Pereira, and Romulo Môra. "PHYSICAL PROPERTIES AND PRESERVATIVE TREATMENT OF EUCALYPTUS AND CORYMBIA WOOD." FLORESTA 51, no. 2 (March 16, 2021): 410. http://dx.doi.org/10.5380/rf.v51i2.69280.

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The properties of wood influence its use as a final product, so it is essential to know their relation and influence on the quality of preservation. In this sense, for the present study we aim at the determination of the physical properties of Corymbia citriodora [Eucalyptus citriodora Hook]; Eucalyptus camaldulensis Dehnh. and Eucalyptus camaldulensis Dehn. x Eucalyptus grandis, and the quality of the preservative treatment with CCA-C in an autoclave. We determined diameter, heartwood and sapwood percentages, and their relationship, as well as the basic density for the three genetic materials. The quality of the preservation was evaluated through the area treated and not treated by CCA, besides its penetration and retention. The highest proportion of sapwood, treated area, and highest density value was found in C. citriodora, whereas the hybrid E. camaldulensis x E. grandis presented the highest level of CCA retention. The diameter and density showed the highest correlation with CCA retention in wood, the length and moisture of the small logs also shown to be influential. All clones presented satisfactory chemical treatment quality for use as fence posts.

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23

Wang, Ju Wei. "Study on Extraction of Xylan and in Wood Preservation." Applied Mechanics and Materials 703 (December 2014): 102–5. http://dx.doi.org/10.4028/www.scientific.net/amm.703.102.

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Xylan preservative is harmless to humans and animals, contaminate the environment of new wood preservatives.This paper from bagasse, rice husk, corncob, xylan extracted from birch, testing the corrosion resistance of these four preservatives and CCA compared with the results show that: white rot fungus specimen weight loss rates were: Bagasse xylan: 2.41%, rice husk xylan: 2.65%, corn cob xylan: 2.53%, birch xylan: 2.33%, CCA rate of 4.08% weight loss.

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24

Tomeleri, João Otávio Poletto, Luciano Donizeti Varanda, Leonardo Machado Pitombo, Fabio Minoru Yamaji, and Franciane Andrade de Pádua. "Influence of Non-Lignocellulosic Elements on the Combustion of Treated Wood and Wooden Panel." Sustainability 13, no. 9 (May 5, 2021): 5161. http://dx.doi.org/10.3390/su13095161.

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Brazil stands out internationally in the production and commercialization of wood products. Although the external and internal demand for these products is met by the Brazilian forestry sector, challenges related to the internal management of lignocellulosic waste are evident, as the country has structural difficulties in the sector of solid waste management. Therefore, the objective was to comparatively analyze the performance of the most abundant lignocellulosic materials in the Brazilian market, regarding energy recovery at the end of their life cycles. Pine wood treated with chromed copper arsenate (CCA), untreated pine wood, eucalypt wood treated with CCA, untreated eucalypt wood, uncoated medium density fiberboard panel (MDF), and MDF panel with melamine coating were sampled. The characterization included thermogravimetric analysis (TGA), scanning electron microscopy (SEM) with energy-dispersive x-ray spectroscopy (EDXA), and elementary analysis (EA). The presence of the CCA salts and the melamine coating reduced the energy potential of the biomass, altering the burning behavior and significantly increasing the amount of generated ashes. They also caused an increase in the concentrations of copper (Cu), chromium (Cr), arsenic (As), and cadmium (Cd) in the wood ashes as well as lead (Pb) and chromium in the panel ashes.

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25

Stevanovic-Janezic, Tatjana, and Paul A. Cooper. "Characteristics of Sludges Produced by Destabilization of CCA Preservative Solutions." Holzforschung 55, no. 5 (September 19, 2001): 471–77. http://dx.doi.org/10.1515/hf.2001.078.

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Summary Chromated copper arsenate (CCA) working solution is partially destabilized over time as a result of hexavalent chromium (CrVI) reduction by wood extractives and reactive additives such as water repellents and polyethylene glycol (PEG) wood softening agents. Hot water extracts of several softwood and hardwood species were used to prepare 2% CCA type C solutions. The softwoods included sapwood and heartwood of red pine (Pinus resinosa Ait.), jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana Mill.), balsam fir (Abies balsamea (L.) Mill.) and sapwood of southern yellow pine (Pinus spp.). Hard wood samples were mixed sapwood and heartwood of red maple (Acer rubrum L.), basswood (Tilia americana L.), yellow poplar (Liriodendron tulipifera L.) and red oak (Quercus rubra L.). In a similar way, 2% CCA solutions were prepared containing 4% PEG and 1% paraffin wax formulated water repellent. The pH and hexavalent chromium content of the CCA solutions were monitored over time until sludge formation was observed. The obtained sludges were separated and analyzed by Fourier Transform Infrared Spectroscopy (FT-IR) in the mid-infrared range and by atomic absorption spectroscopy (AAS) for chromium, copper and arsenic contents. The results of FT-IR and AAS analyses of the sludges indicate that the products of sludging are of comparable chemical nature regardless of the agent responsible for the destabilization of CCA solutions. Arsenic and chromium are the major and copper the minor constituent of the sludges produced by destabilization of CCA solutions examined here.

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26

Fell, David R., Jon Thomas, and Eric Hansen. "Evolving consumer preferences for residential decking materials." Forestry Chronicle 82, no. 2 (March 1, 2006): 253–58. http://dx.doi.org/10.5558/tfc82253-2.

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Major changes are taking place in the residential decking market driven by concerns over wood preservatives and the resulting phase-out of chromated copper arsenic (CCA)-treated wood and recent entry into the marketplace by wood-plastic composites. Using conjoint analysis, this study explores consumer perceptions regarding residential decking materials over two time periods, 2000 and 2003. Type of material and lifetime were the most important decking attributes. Of lesser importance were annual maintenance and price. Major changes took place over the three-year study period with respect to opinions towards treated wood and wood-plastic composites. Consumers became much more negative towards treated wood and wood-plastic composites received nearly equivalent gains. The CCA controversy clearly had an impact in the marketplace and we demonstrate the usefulness of conjoint analysis in capturing this change. Key words: decking, consumer, conjoint analysis, plastic lumber, treated wood, cedar, substitution

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27

Li, Gan, Darrel D. Nicholas, and Tor P. Schultz. "Development of an accelerated soil-contact decay test." Holzforschung 61, no. 2 (March 1, 2007): 214–18. http://dx.doi.org/10.1515/hf.2007.037.

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Abstract An accelerated method to evaluate wood preservatives for soil contact was explored using thin (4 mm) pine sticks in small decay cups containing non-sterile soil and wood compost-amended soil. The extent of wood decay was measured by monitoring changes in the bending elasticity (MOE) of the test samples, which was found to be a sensitive measure of the decay extent for both chromated copper arsenate (CCA)- and copper naphthenate (CuNap)-treated wood, and untreated wood. The decay rate was rapid, with significant decay detected in untreated wood after only 2 months of exposure. Decay in both treated and untreated wood samples was observed sooner when the soil was amended with wood compost. The compost-amended soil also gave significantly higher copper depletion for CCA- but not CuNap-treated wood. Although the results from this test should not be extrapolated to predict field test performance, it does appear to be applicable for rapid comparison of the performance of new and established preservative systems.

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28

DIAS, K. B., and R. M. BARREIROS. "PRESERVATIVES FOR RAPID GROWTH TIMBER - A REVIEW." Periódico Tchê Química 15, no. 30 (August 20, 2018): 241–51. http://dx.doi.org/10.52571/ptq.v15.n30.2018.244_periodico30_pgs_241_251.pdf.

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The shortage of species that are resistant to biological deterioration has forced man to use less durable, mainly fast-growing, reforestations, such as some species of Eucalyptus and Pinus. These species have moderate or no resistance to the attack of biological agents and require condoms. The decomposition of wood and other cellulosic materials by fungi causes significant economic loss. Until recently, the most widely used wood preservative was chromium copper arsenate (CCA). However, the use of CCA in the treatment of wood has been banned for more than a decade because of issues raised regarding the environmental impact and safety of arsenic and chromium. As CCA replacements, arsenic-free and chrome-free wood preservatives are sought. Thus, the aim of research has been to develop environmentally correct and effective products against the attack of biodeteriorating agents. This article reviews the alternatives you have searched for. The search for alternatives to current condoms has been efficient, but not effective, that is, a viable alternative to existing products has not yet been found. Based on several studies, the demand for a preservative for wood can be divided into extractives of plants and by-products of processes.

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29

Yazdani, Nur, Joy O. Kadnar, James A. Kainz, and Mike Ritter. "Parametric Study on Behavior of Stress-Laminated Southern Pine Bridge Decks." Transportation Research Record: Journal of the Transportation Research Board 1740, no. 1 (January 2000): 85–95. http://dx.doi.org/10.3141/1740-11.

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Stress-laminated timber bridge decks have gained popularity in the United States in recent years. As with all wood exposed to the environment, wood for these decks must be treated with preservatives. There has been reluctance to build chromated copper arsenate (CCA)-treated wood bridges because of concerns about dimensional stability. Because no research has been undertaken to investigate the use of CCA-treated southern pine stress-laminated bridge decks, a good resource for economical rural bridges has remained untapped. The objective of the present study was to evaluate the performance of various wood preservatives on stress-laminated southern pine bridge decks. A total of nine decks with seven different preservatives were built and exposed to the environment for more than 2 years. Force levels in prestressing rods and wood moisture contents from each deck were continuously monitored. It was found that the short-term variations in the rod stress levels are less for decks with oil-type preservatives than for decks with CCA preservatives. The long-term performances of decks with both preservative types were found to be similar. The anchorage effect on deck performance was found to be negligible.

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30

Tupper, C., A. J. Pitman, and S. M. Cragg. "Copper Accumulation in the Digestive Caecae of Limnoria quadripunctata Holthius (Isopoda: Crustacea) Tunnelling CCA-Treated Wood in Laboratory Cultures." Holzforschung 54, no. 6 (October 25, 2000): 570–76. http://dx.doi.org/10.1515/hf.2000.097.

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Summary To investigate the mechanisms by which the isopod Limnoria tolerates copper, chromium and arsenic when tunnelling CCA-treated wood in the marine environment, digestive caecae of specimens of L. quadripunctata from CCA-treated and untreated Pinus sylvestris sapwood were examined using transmission electron microscopy (TEM) and energy dispersive X-ray detection (EDX). Copper-containing granules were found to be present in the small cells of the digestive caecae (midgut) of Limnoria from both treated and untreated wood. However, individuals tunnelling treated timber contained a greater number of granules, with six types of morphology being distinguished of which only two were present in Limnoria from untreated wood. The presence of copper-containing granules in Limnoria from untreated timber may be explained by the ability of this isopod to acquire and store copper from seawater for use in enzymes and blood pigments. The increased number of copper granules in individuals tunnelling treated wood was believed to result from elevated levels of this element in the food substrate. This ability to store copper allows these organisms to tolerate this metal in the wood substrate and may explain how this organism is able to attack CCA-treated wood in service. No chromium, or arsenic, was detected in the digestive caecal cells.

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31

Takahashi, Naofumi, Toshinori Yoshida, Sayuri Kojima, Satoru Yamaguchi, Ryoichi Ohtsuka, Makio Takeda, Tadashi Kosaka, and Takanori Harada. "Pathological and Clinical Pathological Changes Induced by Four-week, Repeated-dose, Oral Administration of the Wood Preservative Chromated Copper Arsenate in Wistar Rats." Toxicologic Pathology 46, no. 3 (March 27, 2018): 312–23. http://dx.doi.org/10.1177/0192623318765392.

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Chromated copper arsenate (CCA) is used as a wood preservative worldwide. Exposure to it may adversely affect human health. Some events have increased human exposure to CCA, including the Great East Japan Earthquake, which generated a large amount of lumber debris from CCA-treated woods. We elucidated the toxicity due to daily exposure to CCA over a 4-week period at doses of 0, 8, 40, and 80 mg/kg/day in Wistar Hannover rats. Chromium (Cr) and arsenic (As), but not copper, were detected in the plasma samples of rats treated with various doses of CCA. Males and females showed sedation, and males had poor body weight gain. The clinical pathologies observed in both sexes included hypochromic and microcytic anemia, hepatic and renal dysfunction, and changes in lipid and glucose levels. Histopathologically, males and females showed forestomach hyperkeratosis, mucosal epithelial hyperplasia in the small intestine, rectal goblet cell hypertrophy, and lipofuscin deposition in the proximal renal tubule. Females showed diffuse hepatocellular hypertrophy with increased 8-hydroxydeoxyguanosine levels. These results indicated that oral administration of CCA mainly affected hematopoietic, gastrointestinal, hepatic, and renal systems owing to the toxic effects of As and/or Cr. Major toxic effects were observed in both sexes receiving 40 and 80 mg/kg/day.

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32

Choi, Yong-Seok, Jae-Jin Kim, Tsuyoshi Yoshimura, and Gyu-Hyeok Kim. "Oxalic acid production and metal removal during fungal degradation of CCA-treated wood in nutrient culture." Holzforschung 68, no. 6 (August 1, 2014): 685–91. http://dx.doi.org/10.1515/hf-2013-0169.

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Abstract The objective of this study was to evaluate characteristics of oxalic acid (OA) production and metal removal during degradation of CCA-treated wood in nutrient culture by brown-rot fungi. Two brown-rot fungi, Crustoderma sp. and Fomitopsis palustris extensively degraded the CCA-treated wood, causing mass losses (MLs) up to 49.0% and 43.5%, respectively, while these fungi produced OA during degradation up to 21.3 mg g-1 and 43.8 mg g-1, respectively. Antrodia vaillantii and Polyporales sp. produced OA up to 28.9 mg g-1 and 29.8 mg g-1, respectively, with <3% ML. Fomitopsis palustris with the highest OA production removed effectively 87.5% As and 86.0% Cr during degradation of the treated wood. Antrodia vaillantii and an unknown Polyporales sp. showed notable As removal rates of 90.3% and 88.9%, respectively, and 81.0–83.9% Cr removal. However, only moderate amounts of Cu (40.8%) were extracted by the fungi investigated. The conclusion is that OA production by brown-rot fungi can be partially associated with removal of Cr and As during fungal degradation of CCA-treated wood.

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33

Chou, Selene, Joan Colman, Carolyn Tylenda, and Christopher De Rosa. "Chemical-specific health consultation for chromated copper arsenate chemical mixture: port of Djibouti." Toxicology and Industrial Health 23, no. 4 (May 2007): 183–208. http://dx.doi.org/10.1177/0748233707076810.

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The Agency for Toxic Substances and Disease Registry (ATSDR) prepared this health consultation to provide support for assessing the public health implications of hazardous chemical exposure, primarily through drinking water, related to releases of chromated copper arsenate (CCA) in the port of Djibouti. CCA from a shipment, apparently intended for treating electric poles, is leaking into the soil in the port area. CCA is a pesticide used to protect wood against decay-causing organisms. This mixture commonly contains chromium(VI) (hexavalent chromium) as chromic acid, arsenic(V) (pentavalent arsenic) as arsenic pentoxide and copper (II) (divalent copper) as cupric oxide, often in an aqueous solution or concentrate. Experimental studies of the fate of CCA in soil and monitoring studies of wood-preserving sites where CCA was spilled on the soil indicate that the chromium(VI), arsenic and copper components of CCA can leach from soil into groundwater and surface water. In addition, at CCA wood-preserving sites, substantial concentrations of chromium(VI), arsenic and copper remained in the soil and were leachable into water four years after the use of CCA was discontinued, suggesting prolonged persistence in soil, with continued potential for leaching. The degree of leaching depended on soil composition and the extent of soil contamination with CCA. In general, leaching was highest for chromium(VI), intermediate for arsenic and lowest for copper. Thus, the potential for contamination of sources of drinking water exists. Although arsenic that is leached from CCA-contaminated soil into surface water may accumulate in the tissues of fish and shellfish, most of the arsenic in these animals will be in a form (often called fish arsenic) that is less harmful. Copper, which leaches less readily than the other components, can accumulate in tissues of mussels and oysters. Chromium is not likely to accumulate in the tissues of fish and shellfish. Limited studies of air concentrations during cleanup of CCA-contaminated soil at wood- preserving sites showed that air levels of chromium(VI), arsenic and copper were below the occupational standards. Workers directly involved in the repackaging, containment or cleanup of leaking containers of CCA or of soil saturated with CCA, however, may be exposed to high levels of CCA through direct dermal contact, inhalation of aerosols or particulates and inadvertent ingestion. Few studies have been conducted on the health effects of CCA. CCA as a concentrated solution is corrosive to the skin eyes and digestive tract. Studies of workers exposed to CCA in wood-preserving plants have not found adverse health effects in these workers, but the studies involved small numbers of workers and therefore are not definitive. People exposed to very high levels of CCA, from sawing wood that still had liquid CCA in it or from living in a home contaminated with ash containing high levels of chromium(VI), arsenic and copper, experienced serious health effects including nosebleeds, digestive system pain and bleeding, itching skin, darkened urine, nervous system effects such as tingling or numbness of the hands and feet and confusion, and rashes or thickening and peeling of the skin. These health effects of the mixture are at least qualitatively reflective of the health effects of the individual components of CCA (arsenic, chromium(VI) and copper). For a given mixture, the critical effects of the individual components are of particular concern, as are any effects in common that may become significant due to additivity or interactions among the components. Effects of concern for CCA, based on the known effects of the individual components, include cancer (arsenic by the oral route, arsenic and chromium(VI) by the inhalation route), irritant or corrosive effects (all three mixture components), the unique dermal effects of arsenic, neurologic effects (arsenic and chromium(VI), and hematologic, hepatic and renal effects (all three components). Because arsenic, chromium(VI), and copper components affect some of the same target organs, they may have additive toxicity toward those organs. Few studies have investigated the potential toxic interactions among the components (arsenic, chromium(VI) and copper) of CCA. The available interaction studies and also possible mechanisms of interaction were evaluated using a weight-of-evidence approach. The conclusion is that there is no strong evidence that interactions among the components of CCA will result in a marked increase in toxicity. This conclusion reflects a lack of well designed interaction studies as well as uncertainties regarding potential mechanisms of interaction. Confidence in the conclusion is low. Workers exposed to high levels of CCA during cleanup of leaking containers of CCA or soil heavily contaminated with CCA should wear protective clothing and respirators if air concentrations of arsenic are above 10 μg/m3. In addition, they should not eat, drink or use tobacco products during exposure to CCA, and should thoroughly wash after skin contact with CCA and before eating, drinking, using tobacco products or using restrooms. When protective clothing becomes contaminated with CCA, it should be changed, and the contaminated clothing should be disposed off in a manner approved for pesticide disposal. Workers should leave all protective clothing, including work shoes and boots, at the workplace, so that CCA will not be carried into their cars and homes, which would endanger other people. People not involved in the cleanup of the CCA and who are not wearing protective clothing should be prevented from entering contaminated areas. Leaking containers of CCA must be repackaged and contained to prevent direct exposure of on-site personnel; and contaminated soil needs to be removed to prevent the CCA from leaching into surface water and groundwater, thereby contaminating sources of drinking water.

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34

Lin, Lianzhen, and Chung-Yun Hse. "Liquefaction of CCA-treated wood and elimination of metals from the solvent by precipitation." Holzforschung 59, no. 3 (May 1, 2005): 285–88. http://dx.doi.org/10.1515/hf.2005.047.

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Abstract Spent chromated copper arsenate (CCA)-treated wood was liquefied in polyethylene glycol 400/glycerin (2:1w/w). Sulfuric acid (95–98%) and ferrous salts (FeSO4·7H2O or FeCl2·4H2O) were used as catalysts and additives, respectively. The resulting liquefied CCA-treated wood was diluted with aqueous solvents and was then mixed with complexion/precipitation agents, followed by precipitation or filtration to remove the toxic metal-bearing sediment. As a result, more than 90% of Cu, Cr or As was removed.

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35

Stevanovic-Janezic, T., P. A. Cooper, and Y. T. Ung. "Chromated Copper Arsenate Preservative Treatment of North American Hardwoods. Part 2. CCA Leaching Performance." Holzforschung 55, no. 1 (December 14, 2001): 7–12. http://dx.doi.org/10.1515/hf.2001.002.

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Summary Seven North American hardwood species were vacuum or vacuum/pressure treated with 2% CCA-C solution and fixed at temperatures of 21°C and 50°C under conditions of high relative humidity (95%). The rates of fixation results are presented in Part 1 of this study. Red maple (Acer rubrum L.), red oak (Quercus rubra L.), American beech (Fagus grandifolia Ehrh), white birch (Betula papyrifera Marsh.), trembling aspen (Populus tremuloides Michx.), basswood (Tilia americana L.) and yellow poplar (Liriodendron tulipifera L.) were evaluated. The softwood red pine (Pinus resinosa Ait.) was included for comparison. Adequately fixed wood blocks (99.9% chromium reduction) were exposed to leaching by the AWPA E11 procedure. All CCA components were leached in high quantities from oak wood, while from red maple and beech, high arsenic leaching occurred. Leaching losses from aspen, basswood and yellow poplar were low and comparable for both fixation temperatures. In most species, the amount of leaching was affected by the treating method, with lower leaching from pressure treated wood blocks than from vacuum treated blocks. Removal of extractives from maple and oak blocks before treatment affected the CCA leaching performance in these species. Extracted red oak had lower chromium and copper leaching, but higher arsenic leaching. In contrast, extracted red maple had reduced leaching of all CCA components compared to unextracted wood. The examined hardwoods can be classified into three groups according to their CCA fixing and leaching characteristics: fast fixing/high leaching group (beech, red oak and red maple), intermediate fixation rate and leaching group (white birch and red pine) and slow fixing and low leaching group (aspen, yellow poplar and basswood).

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36

Pizzi, A. "Chromium Interactions in CCA/CCB Wood Preservatives. Part I. Interactions with Wood Carbohydrates." Holzforschung 44, no. 5 (January 1990): 373–80. http://dx.doi.org/10.1515/hfsg.1990.44.5.373.

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37

Abd El-Fatah, Samir, Motonobu Goto, Akio Kodama, and Tsutomu Hirose. "Supercritical fluid extraction of hazardous metals from CCA wood." Journal of Supercritical Fluids 28, no. 1 (January 2004): 21–27. http://dx.doi.org/10.1016/s0896-8446(03)00005-6.

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38

Helsen, L., E. Van den Bulck, S. Mullens, and J. Mullens. "Low-temperature pyrolysis of CCA-treated wood: thermogravimetric analysis." Journal of Analytical and Applied Pyrolysis 52, no. 1 (September 1999): 65–86. http://dx.doi.org/10.1016/s0165-2370(99)00034-0.

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39

TOWNSEND, T., H. SOLOGABRIELE, T. TOLAYMAT, and K. STOOK. "Impact of chromated copper arsenate (CCA) in wood mulch." Science of The Total Environment 309, no. 1-3 (June 20, 2003): 173–85. http://dx.doi.org/10.1016/s0048-9697(03)00047-0.

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40

Kartal, S. N., and C. Kose. "Remediation of CCA-C treated wood using chelating agents." Holz als Roh- und Werkstoff 61, no. 5 (October 1, 2003): 382–87. http://dx.doi.org/10.1007/s00107-003-0412-7.

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41

Rahman, Farhana Alamgir, Deborah L. Allan, Carl J. Rosen, and Michael J. Sadowsky. "Arsenic Availability from Chromated Copper Arsenate (CCA)–Treated Wood." Journal of Environment Quality 33, no. 1 (2004): 173. http://dx.doi.org/10.2134/jeq2004.0173.

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42

Rahman, Farhana Alamgir, Deborah L. Allan, Carl J. Rosen, and Michael J. Sadowsky. "Arsenic Availability from Chromated Copper Arsenate (CCA)-Treated Wood." Journal of Environmental Quality 33, no. 1 (January 2004): 173–80. http://dx.doi.org/10.2134/jeq2004.1730.

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43

Ruddick, John N. R., Koichi Yamamoto, Philip C. Wong, and Keith A. R. Mitchell. "X-Ray Photoelectron Spectroscopic Analysis of CCA-Treated Wood." Holzforschung 47, no. 6 (January 1993): 458–64. http://dx.doi.org/10.1515/hfsg.1993.47.6.458.

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44

TOWNSEND, T., T. TOLAYMAT, H. SOLOGABRIELE, B. DUBEY, K. STOOK, and L. WADANAMBI. "Leaching of CCA-treated wood: implications for waste disposal." Journal of Hazardous Materials 114, no. 1-3 (October 18, 2004): 75–91. http://dx.doi.org/10.1016/j.jhazmat.2004.06.025.

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45

Nelson, Jacob, Kim L. Pickering, and Mohammad D. H. Beg. "Assessment of the Potential of Waste Copper Chromium and Arsenic (CCA)-Treated Timber Fibre Reinforced Polypropylene Composites for Construction." Journal of Composites Science 7, no. 2 (January 25, 2023): 48. http://dx.doi.org/10.3390/jcs7020048.

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This paper investigates the potential of recycling waste copper chromium and arsenic (CCA)-treated timber for use as a reinforcement material in wood–plastic composites (WPCs) produced for use in construction, including an assessment of mechanical properties and the leaching of heavy metals. Wood flour was obtained through mechanical grinding, and fibres were obtained through alkaline digestion followed by bleaching. Composites produced with 40 wt.% bleached fibres showed increased tensile strength from 18.5 MPa for the polypropylene used as the matrix to 27.6 MPa. Likewise, the Young’s modulus was increased from 0.84 to 2.33 GPa. The treatment of fibres was found to reduce arsenic concentration by up to 99.9%. Furthermore, the arsenic in the leachate from composites was found to decrease from 41.29 to 0.07 ppb when comparing CCA-treated wood flour composites to bleached fibre composites. The composites’ material properties indicate that the use of end-of-life CCA-treated timber could be used to produce a composite material that could be used in New Zealand’s building sector to meet the requirements of semi-structural applications.

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46

Decker, Paul, Beverly Cohen, John H. Butala, and Terry Gordon. "Exposure to Wood Dust and Heavy Metals in Workers Using CCA Pressure-Treated Wood." AIHAJ 63, no. 2 (March 2002): 166–71. http://dx.doi.org/10.1202/0002-8894(2002)063<0166:etwdah>2.0.co;2.

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47

Decker, Paul, Beverly Cohen, John H. Butala, and Terry Gordon. "Exposure to Wood Dust and Heavy Metals in Workers Using CCA Pressure-Treated Wood." AIHA Journal 63, no. 2 (March 2002): 166–71. http://dx.doi.org/10.1080/15428110208984700.

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48

Choi, Yong-Seok, Byoung Jun Ahn, and Gyu-Hyeok Kim. "Extraction of chromium, copper, and arsenic from CCA-treated wood by using wood vinegar." Bioresource Technology 120 (September 2012): 328–31. http://dx.doi.org/10.1016/j.biortech.2012.06.045.

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49

Matsumoto, Takahiko, Hiroyuki Matsuura, and Fumitaka Tsukihashi. "Oxidation and Evaporation Behaviors of Cr, Cu and As During Incineration of Wood Treated by Chromated Copper Arsenate Preservative." High Temperature Materials and Processes 31, no. 4-5 (October 30, 2012): 559–68. http://dx.doi.org/10.1515/htmp-2012-0093.

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AbstractWoody materials treated by chromated copper arsenate (CCA) preservative containing copper, chromium and arsenic had been widely used, and thus it is anticipated that a lot of wood waste treated by CCA will be generated as the industrial waste in the future. The environmental pollution by the released heavy metals becomes a serious problem when the wood treated by CCA was incinerated inadequately. There needs the investigation for the behaviors of heavy metals during incineration of wood treated by CCA.The wood sample treated by CCA was incinerated at temperature range between 873 and 1673 K with the oxygen partial pressure between 0.21 and 0.40 atm completely. The proportion of evaporated arsenic increased with increasing temperature and most of arsenic evaporated at about 1600 K. It was suggested that arsenic evaporated as As2O3 or As4O6 during the incineration. On the other hand, most of copper and chromium remained in the bottom ash. The evaporation behaviors of arsenic largely depended on the incineration temperature, while the effects of the oxygen partial pressure of inlet gas and gas flow rate on those were small. Powder XRD analysis of bottom ash revealed that copper and chromium existed as CuCr2O4 and CuCrO2. CuCr2O4 was mainly contained in the bottom ash incinerated at temperature below 1273 K, whereas the ratio of CuCrO2 increased with increasing incineration temperature above 1273 K. Therefore, most of copper and chromium were bivalent and trivalent, respectively, in the bottom ash, and some copper was converted to a monovalent over 1273 K. Almost all arsenic was contained as pentavalent Cu3(AsO4)2, and arsenic was not identified in bottom ash incinerated at temperature above 1273 K.

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50

Tripathi, Sadhna, and J. Bagga. "Suitability of Eucalyptus hybrid, Melia azedarach and Mangifera indica treated with CCA, ACA and copper lignate in cooling tower." Indian Journal of Forestry 31, no. 2 (June 1, 2008): 209–16. http://dx.doi.org/10.54207/bsmps1000-2008-71t7s6.

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Eucalyptus hybrid, Mangifera indica and Melia azedarach were treated with different concentrations of CCA, ACA and Copper lignate. Pinus roxburghii (Pine) was also treated with the same preservatives and used as reference species. Two experiments for different periods i.e. 4 and 5 years were conducted in the same cooling tower. Observations in terms of weight loss were taken. It was found that Melia azedarach (Melia), Pinus roxburghii and Eucalyptus hybrid (Eucalyptus) performed excellently when treated with CCA at 16 kg/m3 retention throughout the period of investigation. While ACA (16 kg/m3) and CCA (i) (consisting As2O3.2H2O) treated samples were protected considerably but were not comparable with CCA treated samples. Copper lignate (1.0, 1.5 and 2.0 kg/m3) treated samples (10 x 2.5 x 0.6 cm3) of all species, could not perform satisfactorily. Visual observations of Mangifera indica (Mango) samples indicated heavy attack of soft rot fungus on the sample in the 3rd year of experiment itself, thus indicating none of the preservative treatment being able to protect Mango wood samples. Thus, Eucalyptus hybrid (heartwood) and Melia azedarach treated with CCA can be recommended for smaller size samples used in cooling towers whereas for bigger size of wood used in cooling towers, where strength is important criteria, bigger samples i.e. stake test (45 x 5 x 4 cm3) is required.

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