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Our previous 4-week repeated dose toxicity study showed that wood preservative chromated copper arsenate (CCA) induced hepatocellular hypertrophy accompanied by biochemical hepatic dysfunction and an increase in oxidative stress marker, 8-hydroxydeoxyguanosine, in female rats. To further explore the molecular mechanisms of CCA hepatotoxicity, we analyzed 10%-buffered formalin-fixed liver samples from female rats for cell proliferation, apoptosis, and protein glutathionylation and conducted microarray analysis on frozen liver samples from female rats treated with 0 or 80 mg/kg/day of CCA. Chemical analysis revealed that dimethylated arsenical was the major metabolite in liver tissues of male and female rats. CCA increase labeling indices of proliferating cell nuclear antigen and decrease terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling accompanied with increased expression of protein glutathionylation, indicating a decrease in glutathione (GSH) in hepatocytes of female rats. Microarray analysis revealed that CCA altered gene expression of antioxidants, glutathione-S-transferase (GST), heat shock proteins and ubiquitin-proteasome pathway, cell proliferation, apoptosis, DNA methylation, cytochrome P450, and glucose and lipid metabolism in female rats. Increased expression of GSTs, including Gsta2, Gsta3, Mgstl, and Cdknlb (p27), and decreased expression of the antioxidant Mtl, and DNA methylation Dnmtl, Dnmt3a, and Ctcf were confirmed in the liver of female rats in a dose-dependent manner. Methylation status of the promoter region of the Mtl was not evidently changed between control and treatment groups. The results suggested that CCA decreased GSH and altered the expression of several genes, including antioxidants, GST, and DNA methylation, followed by impaired cell proliferation in the liver of female rats. [ABSTRACT FROM AUTHOR]

Plywood is a structural composite mainly applied in construction. For this purpose, some sort of preservative treatment is recommended to increase its durability. One option of the available treatments is heat treatment, which promotes the modification of the wood properties. This treatment is carried out on the final product (plywood), because it can reduce strength if applied to the veneers. However, no study has proven such a reduction. Therefore, the aim of this work was to evaluate three different temperatures (160 °C, 180 °C and 200 °C) of the heat treatment on the veneer surface and on the physical properties (specific gravity, moisture content and swelling in thickness) and mechanical properties (MOE and MOR in static bending) of Pinus taeda plywood. A reduction was observed in the roughness of the veneer's surfaces and the total extractives content changed, with a minimum value reached in the 160 °C treatment. The plywood specific gravity initially increased with the heat treatment and did not change at higher temperatures, moisture content reduced, and thickness swelling was not affected. There was no change in the mechanical properties of the plywood, evidencing that the veneer heat treatment does not prejudice mechanically the final product. [ABSTRACT FROM AUTHOR]

Preservative treatments increase the durability of wood, and one of the alternative treatments involves the use of chromated copper arsenate (CCA). Due to the toxicity of CCA, the disposal of CCA-treated wood residues is problematic, and burning is considered to provide a solution. The ecotoxicological potential of ash can be high when these components are toxic and mutagenic. The aim of this study was to evaluate the toxicity and genotoxicity of bottom ash leachates originating from CCA-treated wood burning. Physical-chemical analysis of the leachates revealed that in treated wood ashes leachate (CCA-TWBAL), the contents of arsenic and chromium were 59.45 mg.L−1 and 54.28 mg.L−1, respectively. In untreated wood ashes leachate (UWBAL), these contents were 0.70 mg.L−1 and 0.30 mg.L−1, respectively. CCA-TWBAL caused significant toxicity in Lactuca sativa, Allium cepa, and microcrustacean Artemia spp. (LC50 = 12.12 mg.mL−1). Comet assay analyses using NIH3T3 cells revealed that concentrations ranging from 1.0 and 2.5 mg.mL−1 increase the damage frequency (DF) and damage index (DI). According to MTT assay results, CCA-TWBAL at concentrations as low as 1 mg.mL−1 caused a significant decrease in cellular viability. Hemolysis assay analyses suggest that the arsenic and chromium leachate contents are important for the ecotoxic, cytotoxic, and genotoxic effects of CCA-TWBAL. [ABSTRACT FROM AUTHOR]

Wood is extensively used in Brazil and other countries to produce paper, building materials, and furniture, and a large amount of wood waste is produced. Chromated copper arsenate (CCA) is a preservative used in wood treatment because it can inhibit the action on biodeteriorating agents, therefore increasing the durability of the wood. As a result, environmental problems will arise due to the large amount of wood waste treated with CCA. The wasted CCA-treated wood is used as a fuel, resulting in the emission of toxic chemical compounds. Therefore, the aim of this work was to determine the toxicological effects of fly ash from the combustion of wood treated with CCA compared to the fly ash from untreated wood. Commercial samples of treated and untreated wood were subjected to controlled combustion. The particulate material, fly ash, was precipitated in water and in an acidic medium. The effluent from the HNO3 medium was submitted to analysis of metals (As, Cr, Cu) and polycyclic aromatic hydrocarbons (PAHs), and that collected in water was used for analysis of toxicity. The analysis of metals showed the presence of As and Cr in the effluent, main components of the chromated copper arsenate (CCA) salt. The toxicity analysis showed, in most cases, a significant increase in toxicity of the effluent from the combustion of the treated wood. However, there was some toxic effect on the effluent from the fly ashes of the untreated wood due to the presence of PAHs in them.

The remediation of wood preservative–contaminated sites is an important issue due to the carcinogenic nature of some contaminants derived from wood preservatives (e.g., Cr+6, arsenate, and pentachlorophenol). This study evaluated the effects of fertilizer application on remediation potential of co-plantings of Salix interior Rowlee. (Salix) and Festuca arundinacea Schreb. (Festuca) in a wood preservative–spiked technosol while considering the potential contaminant and nutrient leaching. Two levels of nitrogen (N) and phosphorus (P) fertilizers, NaNO3 and NaH2PO4 (25 and 75 mg L−1), were applied to achieve three N:P ratios, i.e., 3:1 (75:25), 1:3 (25:75), and 1:1 (25:25), that were compared with a control treatment (0:0 N:P) in a mesocosm experiment. Roots of the plant supplied with 1:1 and 1:3 N:P had more than double arsenic (As) and copper (Cu) amounts (i.e., biomass × concentration) compared to the control ones. Highest As and Cu amounts in shoots were found for Salix stems and Festuca leaves in the 1:3 and 1:1 N:P treatments, respectively. Arsenic and P leaching was high in mesocosms supplied with 1:3 N:P. Contamination and nutrient leaching in the 1:1 N:P treatment did not differ from the control, except for Cu. In conclusion, 1:1 N:P treatment yielded the best results in terms of metal(loid) uptake and contaminant and nutrient leaching. In 1:1 N:P treatment, the maximum values of percent As, Cr, and Cu in Salix and Festuca aboveground were 0.18%, 0.024%, and 1.20% and 0.89%, 0.08%, and 1.78%, respectively. [ABSTRACT FROM AUTHOR]

Technosols are a major component of urban areas with little to no value, but many benefits can be gained by the use of native plants for their ecological reclamation. The aim of this study is to examine the capacity of North American native woody species to establish in and remediate a wood preservative‐contaminated technosol. Nine species are planted in mesocosms containing highly contaminated or non‐contaminated synthetic technosols. Remediation potential and plant physiology parameters (survival, photosynthesis and root growth) are monitored during one growing season. Results show an inverse relation between species performance ranking in the non‐contaminated technosol compared to ranking in contaminated soil. Overall, Salix bebbiana and Sambucus canadensis show good potential for phytomanagement of heterogenous contaminated technosols, offering the best compromise between performance in non‐contaminated and contaminated soils. Most species are able to phytoextract copper (Cu), with Rhus typhina, Alnus crispa, and S. bebbiana showing the highest Cu concentrations in stems. The use of multiple native species for technosol reclamation can be beneficial due to the heterogeneous nature of soil contaminants. [ABSTRACT FROM AUTHOR]

Fast-growing species are gradually being used more in the Brazilian timber market. Such species are more susceptible to deterioration and require conservative treatment to prolong their service life. This work analyzed the influence of the chromated copper arsenate oxide (CCA-A) treatment on the physical-mechanical properties of the tropical woods Simarouba amara (C20), Cedrelinga catenaeformis (C30), and Erisma uncinatum (C40), which were chosen to cover the three lower strength classes, as prescribed by Brazilian Standard Norm. The CCA-A was applied to the wood with the vacuum-pressure process, which could increase the amount of surface defects and weaken the wood properties. To investigate the influence of this process, complete characterization of the species with and without CCA-A was performed, and a Tukey's multiple comparisons test (5% significance level) was applied. Also, scanning electron microscopy (SEM) images and energy dispersive spectra (EDS) were obtained to investigate the behavior of the preservative at the cellular level. Through the obtained results, it was concluded that the CCA did not affect the physical-mechanical properties of the studied species. [ABSTRACT FROM AUTHOR]

Abstract The physico-chemical factors affecting the distribution, behavior and speciation of chromium (Cr), copper (Cu) and arsenic (As) was investigated at a former wood impregnation site (Fredensborg, Denmark). Forty soil samples were collected and extracted using a sequential extraction technique known as the Chemometric Identification of Substrates and Element Distributions (CISED) and a multivariate statistical tool (redundancy analysis) was applied. CISED data was linked to water-extractable Cr, Cu and As and bioavailable Cu as determined by a whole-cell bacterial bioreporter assay. Results showed that soil pH significantly affected the solid phase distribution of all three elements on site. Additionally, elements competing for binding sites, Ca, Mg and Mn in the case of Cu, and P, in the case of As, played a major role in the distribution of these elements in soil. Element-specific distributions were observed amongst the six identified soil phases including residual pore salts, exchangeable, carbonates (tentative designation), Mn-Al oxide, amorphous Fe oxide, and crystalline Fe oxide. While Cr was strongly bound to non-extractable crystalline Fe oxide in the oxic top soil, Cu and notably, As were associated with readily extractable phases, suggesting that Cu and As, and not Cr, constitute the highest risk to environmental and human health. However, bioavailable Cu did not significantly correlate with CISED identified soil phases, suggesting that sequential extraction schemes such as CISED may not be ideally suited for inferring bioavailability to microorganisms in soil and supports the integration of receptor-specific bioavailability tests into risk assessments as a complement to chemical methods. Graphical abstract Unlabelled Image Highlights • CISED and redundancy analysis was used to assess factors affecting the solid phase distribution of Cr, Cu and As. • pH is the key parameter affecting all three elements. • P with As and Ca, Mg and Mn with Cu could compete for binding sites. • As and Cu were associated with readily extractable phases while Cr was not. • Cu bioavailability to microbes cannot be inferred solely using CISED. [ABSTRACT FROM AUTHOR]

This manuscript provides a brief review about chemical and biological agents used to bioremediate treated wood waste. Wood preservatives have been used to increase wood's useful life, because any species is subject to decay. Studies indicate that the disposal of treated wood after its service has drawn concern and scrutiny. Practices have included disposal in landfills or construction sites as well as destruction by burning, so it is apparent that more environmentally friendly options are needed. To mitigate these problems, acidic agents, fungi, and bacteria can be used as alternatives to remove heavy metals. At optimum temperature and concentration, acids play a major role in the removal process. The process is enhanced when a bioremediation technique is used after chemical extraction. In fact, bioremediation has been shown to be a remarkable technique for recovering copper, arsenic, creosote, and other compounds. The major drawback is the extensive duration of fungal activity for release of heavy metals. [ABSTRACT FROM AUTHOR]

Abstract There is increasing concern about the use of chromated copper arsenate (CCA) treated timber due to the possible leaching of toxic metals or metalloids. CCA-treated timber waste are currently stockpiled across Australia with limited information about their risks to the environment or human health. In this study, the treatment and utilisation of CCA-treated timber waste as garden mulch, garden retaining walls, and soil additive were investigated. Iron materials were used as immobilising agents. The bioavailability of Cr, Cu and As to Spinacia oleracea from CCA-treated timber, before and after treatment, was determined in the context of human health risk assessment. The results showed that the iron-based treatments resulted in significant decreases in the concentrations of Cu and As in spinach grown in CCA-treated timber in soil. Analyses of CCA derived Cu and As in spinach showed that they accumulated in the roots rather than in the leaves. The risks of toxicity to humans varied for different utilisation scenarios and the immobilisation amendments were shown to reduce carcinogenic and non-carcinogenic risks. The information obtained in this study can inform development of utilisation options for CCA-treated timber wastes. Graphical abstract Image 1 Highlights • Iron materials reduced leachability, bioavailability and risks for CCA metal(loid). • As, Cr mainly accumulated in root of spinach rather than leaves. • Most As and Cr present in leaves are As(V) (50–90%) and Cr (III) (50–100%). • Treated mulch showed acceptable low carcinogenic and non-carcinogenic risks. [ABSTRACT FROM AUTHOR]

Pentachlorophenol and chromated copper arsenate (CCA) have been used worldwide as wood preservatives, but these compounds can toxify ecosystems when they leach into the soil and water. This study aimed to evaluate the capacity of four treatment wetland macrophytes, Phalaris arundinacea, Typha angustifolia, and two subspecies of Phragmites australis, to tolerate and treat leachates containing wood preservatives. The experiment was conducted using 96 plant pots in 12 tanks filled with three leachate concentrations compared to uncontaminated water. Biomass production and bioaccumulation were measured after 35 and 70 days of exposure. There were no significant effects of leachate contamination concentration on plant biomass for any species. No contaminants were detected in aboveground parts of the macrophytes, precluding their use for phytoextraction within the tested contamination levels. However, all species accumulated As and chlorinated phenols in belowground parts, and this accumulation was more prevalent under a more concentrated leachate. Up to 0.5 mg pentachlorophenol/kg (from 81 µg/L in the leachate) and 50 mg As/kg (from 330 µg/L in the leachate) were accumulated in the belowground biomass. Given their high productivity and tolerance to the contaminants, the tested macrophytes showed phytostabilization potential and could enhance the degradation of phenols from leachates contaminated with wood preservatives in treatment wetlands.

Abstract A limitation to recycling wood from construction and demolition (C&D) waste is contamination of metals from the inadvertent inclusion of preservative treated wood, in particular wood treated with chromated copper arsenate (CCA) and newer copper-based formulations. To minimize contamination many regions have developed best management practices (BMPs) for separating treated from untreated wood. The objective of this study was to evaluate the fraction of preservative treated wood in recycled C&D wood after the implementation of BMPs, using Florida as a case study. Methods involved collecting recycled C&D wood samples from throughout the state, measuring metals concentrations (As, Cu, and Cr) in the samples to compute the fraction of recycled wood treated with waterborne wood preservatives, and comparing measurements with those taken prior to the formalization of BMPs. Metals concentrations were measured using two methods, one based on traditional laboratory digestion methods and another using a more rapid hand-held X-ray Fluorescence (XRF) device in the field. The proportion of waterborne preservative-treated wood in recycled wood products has reduced significantly in the intervening 20 years (from 6% to 2.9%), and the fraction of CCA-treated wood has been reduced even further, to 1.4%. The remaining fraction of waterborne preservative-treated wood is comprised of new formulations of copper-based preservatives. This suggests that restrictions from the wood preservation industry and best management practices implemented at recycling facilities have been effective in reducing heavy metal contamination from pressure treated lumber in recycled wood products. Graphical abstract Image 1 Highlights • In previous work, 6% of recycled wood was treated with chromated copper arsenate. • Since then, industry-led changes have influenced the recycled wood market. • Copper-based wood preservatives are replacing CCA in the market. • This study found that 1.4% of recycled wood was treated with CCA, 1.5% with copper. • In 20 years, waterborne preservatives in recycled wood has decreased by 50%, CCA by 75%. Best management practices and changes to the preservative wood industry have resulted in a reduction in arsenic-treated wood within recycled C&D wood by a factor of 4. [ABSTRACT FROM AUTHOR]

The genera Eucalyptus and Corymbia are widely used in Brazil. Although they present remarkable applicability, they manifest substantial endsplitting and surface checks, which allows wood decay organisms to penetrate the wood. Thereby, the resistance of Eucalyptus grandis x Eucalyptus urophylla (EU) and Corymbia citriodora (CT) treated with chromated copper arsenate type-C (CCA-C) against fungi decay was evaluated. Seventy-two fence posts were assessed; for each species, there were 18 posts treated with CCA-C and 18 non-treated posts. The posts were 2.20 m long and classified into three classes of diameter. The 2% active ingredient was used with a vacuum-pressure cycle. On each fence, disks measuring 2.0 cm thick were cut at the outcrop zone. Two sets of depths were analyzed: the edge at 0 cm to 1.5 cm as well as the inner part at 1.5 cm to 3.0 cm. The samples were subjected to Postia placenta, Gloeophyllum trabeum, and Trametes versicolor attack. The treatment was effective against all fungi, but for CT, the diameter range of 8 cm to 12 cm was optimal. The treated wood from EU samples reached the lowest weight loss for all fungi. Heartwood-sapwood ratio played a major role. By comparing the non-treated woods, EU yielded the highest mass loss. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: The present study investigates the possible use and effectiveness of starch-stabilized Fe/Cu nanoparticles for in situ immobilization of arsenic in contaminated soils.Materials and methods: For this purpose, 0.04 wt.% starch-stabilized Fe/Cu nanoparticles were synthesized and tested through batch and column tests for the immobilization of arsenic in a loamy soil contaminated by chromated copper arsenate (CCA).Results and discussion: When the CCA-contaminated loamy soil was treated with 0.4 g/L of starch-stabilized Fe/Cu nanoparticles (0.04 wt.%) at a soil-to-liquid ratio of 0.1, water-leachable arsenic was reduced by 92% and the toxicity characteristic leaching procedure (TCLP) leachability was reduced by 98%. Column elution experiments showed that through application of starch-stabilized Fe/Cu nanoparticles to CCA-contaminated soil, nearly all water-soluble arsenic was transferred to the nanoparticle phase. The TCLP leachability of arsenic remaining in the soil column was reduced by 70% due to the immobilization of arsenic by nanoparticles.Conclusions: In addition to an extremely high arsenic sorption capacity, starch-stabilized Fe/Cu nanoparticles exhibited excellent mobility in the soil environment. Both the high sorption capacity and the excellent mobility in the soil environment suggest potential for application of these nanoparticles to the contaminated soil for potential in situ arsenic immobilization. [ABSTRACT FROM AUTHOR]

Plywood can be used in the furniture industry and in civil construction due to its structural strength. However, for long useful life in construction, especially in tropical countries, it needs to undergo treatments against xylophagous organisms. The most common preservative treatment is the chemical chromated copper arsenate (CCA); there are alternatives, such as heat treatment, that do not use chemicals. The objective of this work was to evaluate the mechanical resistance of CCA and heat-treated plywood prepared at three different temperatures (160 °C, 180 °C, and 200 °C). Pinus taeda plywood with seven veneers and phenol-formaldehyde adhesive was produced and subjected to the preservative treatments. The results showed that the CCA treatment reduced the mechanical strength of the panels, while the heat treatment did not. Heat treatment also decreased panel hygroscopicity, indicating a better dimensional stability. [ABSTRACT FROM AUTHOR]

The disposal of eucalyptus poles used in the electricity network distribution is considered a potential contamination to the environment due to the chromated copper arsenate (CCA) used as a wood preservative. The thermochemical process can be an alternative to this toxic waste disposal. In this work, the slow pyrolysis of CCA-treated wood followed by the production and application of activated carbon was proposed. Metal retention (ICP-OES), concentration of non-condensable gases produced in the pyrolysis process (via GC), as well as the capacity of activated carbon on CO 2 adsorption (via TGA) were investigated. The highest formation rate of non-condensable gases was observed at 500 °C, while the maximum H 2 concentration was at 700 °C. The char obtained in the pyrolysis was chemically treated with H 3 PO 4 and activated in CO 2 flow. The pore size distribution of activated carbons showed pore sizes lower than 1 nm. The activated carbons showed a CO 2 adsorption capacity of 70–83 mg/g. The presence of chromium and copper may have influenced the CO 2 adsorption. The fast adsorption and desorption showed by the activated carbon produced from CCA-treated wood is interesting to systems that operate in short-time cycles, as pressure swing adsorption (PSA). The reuse of CCA-treated wood for activated carbon production and its application in the CO 2 adsorption could be a solution to minimize the environmental damage caused by this waste. [ABSTRACT FROM AUTHOR]

The importance of a circular economy is today widely accepted and advocated, but among the challenges in achieving this, we find difficulties in the implementation of legislation and policies designed to control various waste streams from society. The example used in this article is wood that has been treated with chromated copper arsenate (CCA), which, in Sweden, has been covered by the rules for hazardous waste since 2002. One year later, in 2003, a survey showed that only 42% to 50% of the expected amount of CCA waste could be traced to the public waste management system. An updated material flow analysis for 2010 revealed that the figure had increased to 73%, whereas the fraction of correctly treated CCA wood waste had increased from 11% to 35%. However, almost one third of the expected volume was still not tracable, and half of the amount that was correctly submitted was incinerated together with nontoxic waste fractions. This results in, for example, arsenic contamination of slag and fly ashes that prevents the further use of these residue products. So, despite legislative instruments, there is still an urgent need for an improved collection of hazardous wood waste, as well as better routines for identifying hazardous flows and separating them from nonhazardous ones. For a circular economy to be achievable, a key priority should be to reduce the gap between intended directions and legislation, on one hand, and activities in practice on the other. [ABSTRACT FROM AUTHOR]

Effects of natural weathering were studied relative to the adhesion strength, surface hardness, and color change of coated heat-treated and untreated Turkish fir and Scots pine wood. For this study, water-based coatings (varnish and paint) were applied on heat-treated samples. The coated heat-treated, and untreated samples were naturally weathered for one year. The difference between several properties such as adhesion strength, hardness, and color were measured before and after weathering. The test results showed that varnished heat-treated samples had good performance as compared to those of the untreated samples. [ABSTRACT FROM AUTHOR]

The paper discusses the potential of different waste biomaterials for biosorption. Waste biomaterials after citric acid fermentation and chitosan extraction using Aspergillus niger were evaluated for biosorption of toxic metals (Cu, Cr and As) from leachates of chromated copper arsenate woods. The different waste BMs, such as fungal biomass (living and dead), alkali insoluble material and acid and alkali insoluble material were used in this study. The effect of different parameters, such as biosorbent concentration, metal concentration and contact time were investigated. The fitness of biosorption data for Freundlich and Langmuir adsorption models was investigated through batch adsorption technique. Among the adsorption isotherm tested, Langmuir isotherm gave the best fit with correlation coefficients (R 2 ) value ranging from 0.89 to 0.97; 0.96–0.99 and 0.76–0.95 for As, Cr and Cu, respectively using solid state fermented biomass. Similarly, the significant removal of metals (>60% in leachate 2) from waste CCA wood leachate was achieved with the different BMs. Therefore, this study demonstrates the potential of CA fermentation derived waste BMs for biosorption of toxic metals from waste waters. [ABSTRACT FROM AUTHOR]