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Morris H. Roberts - One of the best experts on this subject based on the ideXlab platform.
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Toxicity of water‐soluble fractions derived from whole Creosote and Creosote‐contaminated sediments
Environmental Toxicology and Chemistry, 1998Co-Authors: T.v. Padma, Robert C. Hale, Morris H. RobertsAbstract:Creosote, a complex mixture of aromatic compounds (ACs), contaminates numerous sites in the USA and elsewhere. In addition to pollution of the water column directly after a Creosote spill, contaminated sediments can continue to act as source of pollution for many years, because natural and anthropogenic perturbations may redissolve or resuspend sediment-associated contaminants. A 48-h static renewal assay compared survival of the bay mysid, Mysidopsis bahia, exposed to water-soluble fractions (WSFs) generated from two different sources: whole Creosote and Creosote-contaminated sediment. Sediment was obtained from a Super Fund site located on the Southern Branch of the Elizabeth River in Virginia, USA. Whole Creosote, contaminated sediment, and WSFs derived from these source materials were characterized. Median lethal concentrations of WSFs generated from whole Creosote and sediment (expressed as total identified ACs) were 180 {micro}g/L and 700 {micro}g/L, respectively. The Creosote-derived WSF consisted of more than 70% low molecular weight nitrogen heterocyclics. These heterocyclics were below detectable limits in the sediment-generated WSF, suggesting that losses of these compounds had occurred via weathering. Nitrogen heterocyclics likely contributed to the acute toxicity of the whole Creosote WSF.
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Toxicity and composition of water-soluble fractions derived from neat Creosote and Creosote contaminated sediments
1995Co-Authors: T.v. Padma, Robert C. Hale, Romuald N. Lipcius, Morris H. RobertsAbstract:Creosote, a complex mixture of aromatic compounds (ACs), contaminates numerous sites in the US and elsewhere. A 48 h static renewal assay compared survival of the bay mysid, Mysidopsis bahia, exposed to water soluble fractions (WSFs) generated from two different sources: neat Creosote and Creosote contaminated sediments from a Virginia Super Fund site, where a facility producing Creosote treated lumber was located. Both WSFs and parent materials from which the WSFs were generated (neat Creosote and contaminated sediment) were analyzed using gas chromatography and mass spectrometry. LC50s (expressed in total identified AC) for the WSFs generated from neat Creosote and sediment were: 180 ug/l and 700 ug/l, respectively. The Creosote WSF contained > 70% low molecular weight nitrogen heterocyclics, which were below detectable limits in the sediment generated WSF. Nitrogen heterocyclics were also undetected in sediments, indicating that environmental losses of these compounds had occurred. This qualitative difference likely contributed to the neat Creosote WSF`s four-fold greater toxicity.
Keith R Solomon - One of the best experts on this subject based on the ideXlab platform.
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Creosote toxicity to photosynthesis and plant growth in aquatic microcosms
Environmental toxicology and chemistry, 2003Co-Authors: Christopher A. Marwood, Keith R Solomon, K. T. Jim Bestari, Robert W. Gensemer, Bruce M. GreenbergAbstract:To assess photosynthesis as a bioindicator of toxicity from polycyclic aromatic hydrocarbons (PAHs), the response of chlorophyll-a fluorescence to Creosote exposure was compared with effects on population-level plant growth. Large, outdoor, freshwater microcosms containing Eurasian watermilfoil (Myriophyllum spicatum) received either a single application or multiple applications of liquid Creosote at nominal concentrations from 0.109 to 32.7 mg L(-1). For several weeks following treatment, photosynthetic electron transport was measured using pulse amplitude-modulated chlorophyll-a fluorescence. The maximum efficiency of photosystem II electron transport (Fv/Fm) and the quantum yield of photochemistry (deltaF/F'm) were diminished in plants shortly after the addition of Creosote. In microcosms that received a single treatment of Creosote only, the 50% effective concentrations (EC50s), expressed as the aqueous concentration of 15 of the most abundant PAHs, were 0.28 mg L(-1) for Fv/Fm and 0.30 mg L(-1) for deltaF/F'm. Chlorophyll-a fluorescence was diminished to a greater extent in microcosms that received multiple treatments of Creosote, with EC50s of 0.13 mg L(-1) for Fv/Fm and 0.10 mg L(-1) for deltaF/F'm. Plant biomass accumulation was inhibited in a concentration-dependent manner in all microcosms treated with Creosote, but this inhibition occurred to a greater degree in microcosms treated with multiple Creosote applications. The response of chlorophyll-a fluorescence, measured only 8 d after Creosote treatment, was similar to plant growth over the entire growing season, indicating that this technique can be used to estimate potential effects of contaminants before detrimental impacts on populations.
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effects of Creosote exposure on rainbow trout pronephros phagocyte activity and the percentage of lymphoid b cells
Journal of Toxicology and Environmental Health, 2001Co-Authors: Niel A. Karrow, Keith R Solomon, D.g. Dixon, Jeffrey J. Whyte, Niels C. Bols, Herman J. BoermansAbstract:An outdoor microcosm study was conducted in order to evaluate the kinetics of immunomodulation in rainbow trout (Oncorhynchus mykiss) exposed to liquid Creosote. Fish were sampled on d 7, 14, 21, and 28 from microcosms dosed initially with 0, 3, and 10 µl/L of Creosote. Pronephros leukocytes were monitored for phagocytic activity, oxidative burst, and surface immunoglobulin-positive (SIg+) B-cell counts. Oxidative burst was inhibited by Creosote exposure; however, by sampling d 28, the burst response returned to near control levels. Phagocytic activity, on the other hand, was stimulated, peaking on sampling d 7, then returning to near control levels by d 28. Although control SIg+ B-cell counts were quite variable across sampling days, SIg+ B-cell counts were also elevated in Creosote-exposed fish after seven days of exposure. SIg+ B-cell numbers decreased significantly to near control levels during the remainder of the study. The overall results from this study confirm that Creosote has the potential to a...
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the effect of Creosote on the growth of an axenic culture of myriophyllum spicatum l
Aquatic Toxicology, 2000Co-Authors: Janet H Mccann, Bruce M. Greenberg, Keith R SolomonAbstract:Abstract Due to the importance of submersed, rooted macrophytes to the aquatic ecosystem and the use of Creosote impregnated structures adjacent to or within water bodies, a study was conducted using an axenic culture of Myriophyllum spicatum to determine the effect of Creosote on this aquatic macrophyte. Four plants were cloned and exposed to nominal Creosote concentrations ranging from 0.16 to 200 mg/l for 14 days. A variety of response parameters were assessed, including shoot and root length, number of roots and nodes, and dry weight biomass, as well as visual observations on plant colouring and morphology. Regression and ANOVA analyses were conducted to determine EC50s and significant differences. Biphasic responses were observed for shoot length, node production and biomass, with shoot length showing statistically significant stimulation (hormesis) at Creosote concentrations below 13.3 mg/l. EC50 values of 55.1 (CI 40–60) mg/l, 33.4 (CI 26–48) mg/l and 86 (CI 70–120) mg/l were determined for shoot length, dry weight and node production, respectively. Root number was significantly higher at 3.6 mg/l and root length was significantly reduced at 4.5 mg/l Creosote, within the concentration range that stimulated shoot growth. Visual changes, including an increase in pink colouration and changes in the location of root initiation, were also observed in the same Creosote concentration range that affected root length and numbers. Therefore, it appears that changes in root growth and location of root initiation may be the most sensitive endpoints for Creosote effects on Myriophyllum.
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The effect of Creosote on membrane ion leakage in Myriophyllum spicatum L.
Aquatic toxicology (Amsterdam Netherlands), 2000Co-Authors: Janet H Mccann, Keith R SolomonAbstract:Creosote is a complex chemical mixture used as a wood preservative that has the potential to contaminate aquatic systems via spills or leaching from treated wood structures. Aquatic macrophytes are important components of aquatic systems, which may be adversely affected by Creosote contamination. Several chemicals that are constituents of Creosote are known to affect cell membranes in various organisms. Therefore, the effect of Creosote on the membrane permeability of the aquatic macrophyte Myriophyllum spicatum was investigated. Apical meristems from axenic Myriophyllum plants were exposed for 4 days to 8 Creosote treatments (ranging from 0.1 to 92 mg Creosote/l) plus controls. Following the exposure, the ion leakage from the cellular membranes was determined via conductivity measurements. The concentration of 15 polycyclic aromatic hydrocarbons (PAHs) in the growth medium and in the plant tissue was also determined. A significant increase in ion leakage was observed at all Creosote concentrations, even those in which no biological effects were observed on plant growth. However, saturation of the growth medium with PAHs was observed, thus indicating that nominal Creosote concentrations may over-estimate the actual exposure.
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Characterizing the immunotoxicity of Creosote to rainbow trout (Oncorhynchus mykiss): a microcosm study
Aquatic Toxicology, 1999Co-Authors: Niel A. Karrow, Keith R Solomon, Herman J. Boermans, D.g. Dixon, A Hontella, Jeffrey J. Whyte, Niels C. BolsAbstract:Abstract Several immune parameters were evaluated in rainbow trout (Oncorhynchus mykiss) after they had been exposed for 28 days in microcosms dosed initially with liquid Creosote concentrations of 0, 5, 9, 17, 31, 56 and 100 μl/l. The most noticeable changes were concentration-dependent reductions in pronephros leukocyte oxidative burst and the number of sIg+ peripheral blood leukocytes. Plasma lysozyme levels were reduced, while pronephros leukocyte phagocytic activity was enhanced marginally across Creosote concentrations. Blastogenesis in response to lipopolysaccharide (LPS) was slightly impaired in head kidney leukocyte cultures prepared from Creosote-exposed fish, whereas blastogenesis in response to phytohaemagglutinin (PHA) and concanavalin-A (ConA) was unaffected. Overall the results suggest that Creosote has the potential to alter some innate immune functions in rainbow trout. Polycyclic aromatic hydrocarbons (PAHs), a major constituent of liquid Creosote, are the suspected immune altering agents. The LOEC of the immune responses measured in this study was 17 μl/l using nominal Creosote concentrations, representing a total PAH concentration of 611.63 ng/l in the water.
T.v. Padma - One of the best experts on this subject based on the ideXlab platform.
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Toxicity of water‐soluble fractions derived from whole Creosote and Creosote‐contaminated sediments
Environmental Toxicology and Chemistry, 1998Co-Authors: T.v. Padma, Robert C. Hale, Morris H. RobertsAbstract:Creosote, a complex mixture of aromatic compounds (ACs), contaminates numerous sites in the USA and elsewhere. In addition to pollution of the water column directly after a Creosote spill, contaminated sediments can continue to act as source of pollution for many years, because natural and anthropogenic perturbations may redissolve or resuspend sediment-associated contaminants. A 48-h static renewal assay compared survival of the bay mysid, Mysidopsis bahia, exposed to water-soluble fractions (WSFs) generated from two different sources: whole Creosote and Creosote-contaminated sediment. Sediment was obtained from a Super Fund site located on the Southern Branch of the Elizabeth River in Virginia, USA. Whole Creosote, contaminated sediment, and WSFs derived from these source materials were characterized. Median lethal concentrations of WSFs generated from whole Creosote and sediment (expressed as total identified ACs) were 180 {micro}g/L and 700 {micro}g/L, respectively. The Creosote-derived WSF consisted of more than 70% low molecular weight nitrogen heterocyclics. These heterocyclics were below detectable limits in the sediment-generated WSF, suggesting that losses of these compounds had occurred via weathering. Nitrogen heterocyclics likely contributed to the acute toxicity of the whole Creosote WSF.
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Toxicity and composition of water-soluble fractions derived from neat Creosote and Creosote contaminated sediments
1995Co-Authors: T.v. Padma, Robert C. Hale, Romuald N. Lipcius, Morris H. RobertsAbstract:Creosote, a complex mixture of aromatic compounds (ACs), contaminates numerous sites in the US and elsewhere. A 48 h static renewal assay compared survival of the bay mysid, Mysidopsis bahia, exposed to water soluble fractions (WSFs) generated from two different sources: neat Creosote and Creosote contaminated sediments from a Virginia Super Fund site, where a facility producing Creosote treated lumber was located. Both WSFs and parent materials from which the WSFs were generated (neat Creosote and contaminated sediment) were analyzed using gas chromatography and mass spectrometry. LC50s (expressed in total identified AC) for the WSFs generated from neat Creosote and sediment were: 180 ug/l and 700 ug/l, respectively. The Creosote WSF contained > 70% low molecular weight nitrogen heterocyclics, which were below detectable limits in the sediment generated WSF. Nitrogen heterocyclics were also undetected in sediments, indicating that environmental losses of these compounds had occurred. This qualitative difference likely contributed to the neat Creosote WSF`s four-fold greater toxicity.
Paes, Juarez Benigno - One of the best experts on this subject based on the ideXlab platform.
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Corrosividade causada por soluções produzidas com creosoto vegetal
Revista Árvore, 2002Co-Authors: Paes, Juarez Benigno, Vital, Benedito Rocha, Lucia, Ricardo Marius DellaAbstract:Esta pesquisa teve como objetivo avaliar a corrosividade de soluções preservativas preparadas com creosoto vegetal. Por destilação do alcatrão vegetal, obteve-se o creosoto vegetal bruto, recuperado à temperatura de 110–255 ºC. Uma fração deste destilado foi lavada com solução a 9% de bicarbonato de sódio, obtendo-se o creosoto vegetal purificado. Ambas as frações foram enriquecidas com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% de naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tributil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Foram preparadas 16 soluções preservativas, sendo 14 enriquecidas, além do creosoto vegetal bruto e do creosoto vegetal purificado. Placas de aço SAE 1006 foram expostas por 6 horas às temperaturas de 25, 45 e 100 ºC, à ação corrosiva dessas soluções. A corrosividade das soluções de creosoto vegetal foi comparada à corrosividade causada pelo creosoto mineral. As soluções preparadas com creosoto vegetal purificado foram menos corrosivas que suas similares preparadas com creosoto vegetal bruto, sem, no entanto, atingir a baixa corrosividade do creosoto mineral.The objective of this research was to evaluate the corrosiveness of preservative solutions prepared with wood tar Creosote. By distilling of wood tar, crude wood tar Creosote was recovered at a temperature of 100–255 ºC. A fraction of this product was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar Creosote. Both fractions were enriched with 3% copper naphtenate, 3% zinc naphtenate, 3% cobalt naphtenate, 2% TBTO, 2% tributhyl-tin tribromophenate, 2% pentachlorophenol, or with 0.4% arsenic trioxide. A total of 16 preservative solutions were prepared of which 14 were enriched, besides the crude wood tar Creosote and the purified wood tar Creosote. SAE 1006 steel plates were exposed for 6 hours at temperatures of 25, 45 and 100 ºC, to the corrosive action of those solutions. The corrosiveness of wood tar Creosote solutions was compared with that caused by coal tar Creosote. The solutions with purified wood tar Creosote were less corrosive than similar solutions prepared with crude wood tar Creosote, although being more corrosive than the coal tar Creosote
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Corrosion caused by solutions produced with wood tar Creosote
Sociedade de Investigações Florestais, 2002Co-Authors: Paes, Juarez Benigno, Vital, Benedito Rocha, Della Lucia, Ricardo Marius, Della Lucia, Terezinha Maria CastroAbstract:Esta pesquisa teve como objetivo avaliar a corrosividade de soluções preservativas preparadas com creosoto vegetal. Por destilação do alcatrão vegetal, obteve-se o creosoto vegetal bruto, recuperado à temperatura de 110-255 ºC. Uma fração deste destilado foi lavada com solução a 9% de bicarbonato de sódio, obtendo-se o creosoto vegetal purificado. Ambas as frações foram enriquecidas com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% de naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tributil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Foram preparadas 16 soluções preservativas, sendo 14 enriquecidas, além do creosoto vegetal bruto e do creosoto vegetal purificado. Placas de aço SAE 1006 foram expostas por 6 horas às temperaturas de 25, 45 e 100 ºC, à ação corrosiva dessas soluções. A corrosividade das soluções de creosoto vegetal foi comparada à corrosividade causada pelo creosoto mineral. As soluções preparadas com creosoto vegetal purificado foram menos corrosivas que suas similares preparadas com creosoto vegetal bruto, sem, no entanto, atingir a baixa corrosividade do creosoto mineral.The objective of this research was to evaluate the corrosiveness of preservative solutions prepared with wood tar Creosote. By distilling of wood tar, crude wood tar Creosote was recovered at a temperature of 100-255 ºC. A fraction of this product was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar Creosote. Both fractions were enriched with 3% copper naphtenate, 3% zinc naphtenate, 3% cobalt naphtenate, 2% TBTO, 2% tributhyl-tin tribromophenate, 2% pentachlorophenol, or with 0.4% arsenic trioxide. A total of 16 preservative solutions were prepared of which 14 were enriched, besides the crude wood tar Creosote and the purified wood tar Creosote. SAE 1006 steel plates were exposed for 6 hours at temperatures of 25, 45 and 100 ºC, to the corrosive action of those solutions. The corrosiveness of wood tar Creosote solutions was compared with that caused by coal tar Creosote. The solutions with purified wood tar Creosote were less corrosive than similar solutions prepared with crude wood tar Creosote, although being more corrosive than the coal tar Creosote
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Effects of the purification and enrichment of wood tar Creosote on preservation of Eucalyptus grandis wood, after 48 months of field testing
Sociedade de Investigações Florestais, 2002Co-Authors: Paes, Juarez Benigno, Vital, Benedito Rocha, Della Lucia, Ricardo Marius, Della Lucia, Terezinha Maria CastroAbstract:O objetivo deste trabalho foi avaliar a eficiência da purificação e do enriquecimento do creosoto vegetal contra xilófagos, após 48 meses de instalação do ensaio de campo. Por destilação do alcatrão vegetal, obteve-se o creosoto vegetal bruto (creosoto 1), recuperado à temperatura de 110-255 °C. Uma fração dos destilados foi lavada com solução a 9% de bicarbonato de sódio, para obter o creosoto vegetal purificado (creosoto 2). Os creosotos 1 e 2 foram enriquecidos com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% de naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tributil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Estacas obtidas do alburno de Eucalyptus grandis foram tratadas pelo processo de célula cheia. A eficiência das soluções de creosoto vegetal foi comparada com a do creosoto mineral. O ensaio foi instalado em três localidades (Viçosa, Ponte Nova e Leopoldina). Os resultados indicam que o creosoto 2 + pentaclorofenol foi superior aos creosotos 1 e 2 + TBTO, aos creosotos 1 e 2 + naftenato de zinco e ao creosoto 1 puro, sendo semelhante ao creosoto mineral. O creosoto 2 foi superior ao creosoto 1 apenas para a localidade de Leopoldina. De modo geral, a vida média da madeira não-tratada ficou entre 12 e 24 meses, a da madeira tratada com o creosoto 1 + TBTO entre 24 e 37 meses e a da tratada com o creosoto 1 + naftenato de zinco entre 37 e 48 meses e a com o creosoto 1 + naftenato de cobalto, creosoto 2 puro e creosoto 2 + naftenato de zinco ou TBTO foi de 48 meses. No atual estágio da pesquisa, não é possível estimar a vida média da madeira tratada com as demais soluções preservativas testadas, pois ainda não atingiram os 60% das estacas quebradas.The objective of this work was to evaluate the efficiency of purifying and enriching wood tar Creosote against wood decay after 48 months in field testing. By distillation of wood tar, the crude wood tar (Creosote 1) was recovered at a temperature of 110-255 °C. A fraction of the distilled was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar Creosote (Creosote 2). Creosotes 1 and 2 were enriched with 3% copper naphtenate; 3% zinc naphtenate; 3% of cobalt naphtenate; 2% TBTO; 2% tributil-tin tribromophenate; 2% pentachlorophenol; or 0.4% arsenic trioxide. Stakes of Eucalyptus grandis sapwood were treated by following the full cell process. The efficiency of wood tar Creosote solutions was compared with that of coal tar Creosote. The essay was established in three locations (Viçosa, Ponte Nova and Leopoldina -Minas Gerais, Brazil). The results showed that Creosote 2 + pentaclorofenol was superior to Creosotes 1 and 2 + TBTO, to Creosotes 1 and 2 + zinc naftenato and to pure Creosote 1, being similar to coal tar Creosote. Creosote 2 was superior to Creosote 1, only in Leopoldina. In general, the average life of untreated wood was between 12 and 24 months. The average life of wood treated with Creosote 1 + TBTO was between 24 and 37 months, while that ofwood treated with Creosote 1 + zinc naftenato, between 37 and 48 months and that of wood treated with Creosote 1 + cobalt naftenato, pure Creosote 2, Creosote 2 + zinc naftenato or + TBTO was 48 months. At this stage of research it is not possible to estimate the treated wood average life, as compared with the other tested preservative solutions, it since 60% of the stakes did not break
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Corrosão de parafusos fixados à madeira tratada com soluções de creosoto vegetal
Revista Árvore, 2002Co-Authors: Paes, Juarez Benigno, Vital, Benedito Rocha, Lucia, Ricardo Marius DellaAbstract:O objetivo desta pesquisa foi avaliar a corrosão de parafusos auto-rosqueáveis fixados à madeira tratada com soluções preservativas preparadas com creosoto vegetal, em condições de campo. Obteve-se o creosoto vegetal bruto por meio da destilação à temperatura de 110 – 255ºC do alcatrão vegetal. Uma fração dos destilados foi lavada com solução a 9% de bicarbonato de sódio, obtendo-se o creosoto vegetal purificado. Ambas as frações foram enriquecidas com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tubutil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Foram preparadas 16 soluções, sendo 14 enriquecidas, além do creosoto vegetal bruto e do creosoto vegetal purificado. Estacas confeccionadas com madeira de alburno de Eucalyptus grandis foram tratadas pelo processo de célula- cheia (processo Bethell). Após o tratamento, parafusos auto-rosquéaveis de ferro zincado foram fixados às estacas. O ensaio foi instalado em três localidades da Zona da Mata de Minas Gerais (Viçosa, Ponte Nova e Leopoldina). A corrosividade das soluções de creosoto vegetal foi comparada à causada pelo creosoto mineral. As soluções preparadas com creosoto vegetal purificado foram menos corrosivas que suas similares preparadas com creosoto vegetal bruto, assemelhando-se ao creosoto mineral.The objective of this research was to evaluate the corrosion of screws fixed into wood treated with preservative solutions of wood tar Creosote. The crude wood tar Creosote was obtained through distillation of wood tar at 110 - 255ºC. A fraction of this product was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar Creosote. Both fractions were enriched with 3% of copper naphtenate, 3% of zinc naphtenate, 3% of cobalt naphtenate, 2% of TBTO, 2% of tributhyl-tin tribromophenate, 2% of pentachlorophenol, or with 0.4% of arsenic trioxide. A total of 16 preservative solutions were prepared, of which 14 were enriched, besides the crude wood tar Creosote and the purified wood tar Creosote. Stakes made of Eucalyptus grandis sapwood were treated following the full-cell process (Bethell's process). After the stakes treatment, screws of iron covered with zinc were fixed into the wood stakes. The assay was carried out in three locations (Viçosa, Ponte Nova and Leopoldina - in Zona da Mata, Minas Gerais, Brazil). The corrosiveness of solutions of wood tar Creosote was compared with the one caused by coal tar Creosote. The solutions with purified wood tar Creosote were less corrosive than those prepared with crude wood tar Creosote, being similar to the coal tar Creosote
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Corrosion of screws fixed into wood treated with wood tar Creosote solutions
Sociedade de Investigações Florestais, 2002Co-Authors: Paes, Juarez Benigno, Della Lucia, Ricardo Marius, Benedito Rocha Vital, Della Lucia, Terezinha Maria CastroAbstract:O objetivo desta pesquisa foi avaliar a corrosão de parafusos auto-rosqueáveis fixados à madeira tratada com soluções preservativas preparadas com creosoto vegetal, em condições de campo. Obteve-se o creosoto vegetal bruto por meio da destilação à temperatura de 110 - 255ºC do alcatrão vegetal. Uma fração dos destilados foi lavada com solução a 9% de bicarbonato de sódio, obtendo-se o creosoto vegetal purificado. Ambas as frações foram enriquecidas com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tubutil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Foram preparadas 16 soluções, sendo 14 enriquecidas, além do creosoto vegetal bruto e do creosoto vegetal purificado. Estacas confeccionadas com madeira de alburno de Eucalyptus grandis foram tratadas pelo processo de célula- cheia (processo Bethell). Após o tratamento, parafusos auto-rosquéaveis de ferro zincado foram fixados às estacas. O ensaio foi instalado em três localidades da Zona da Mata de Minas Gerais (Viçosa, Ponte Nova e Leopoldina). A corrosividade das soluções de creosoto vegetal foi comparada à causada pelo creosoto mineral. As soluções preparadas com creosoto vegetal purificado foram menos corrosivas que suas similares preparadas com creosoto vegetal bruto, assemelhando-se ao creosoto mineral.The objective of this research was to evaluate the corrosion of screws fixed into wood treated with preservative solutions of wood tar Creosote. The crude wood tar Creosote was obtained through distillation of wood tar at 110 - 255ºC. A fraction of this product was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar Creosote. Both fractions were enriched with 3% of copper naphtenate, 3% of zinc naphtenate, 3% of cobalt naphtenate, 2% of TBTO, 2% of tributhyl-tin tribromophenate, 2% of pentachlorophenol, or with 0.4% of arsenic trioxide. A total of 16 preservative solutions were prepared, of which 14 were enriched, besides the crude wood tar Creosote and the purified wood tar Creosote. Stakes made of Eucalyptus grandis sapwood were treated following the full-cell process (Bethell's process). After the stakes treatment, screws of iron covered with zinc were fixed into the wood stakes. The assay was carried out in three locations (Viçosa, Ponte Nova and Leopoldina - in Zona da Mata, Minas Gerais, Brazil). The corrosiveness of solutions of wood tar Creosote was compared with the one caused by coal tar Creosote. The solutions with purified wood tar Creosote were less corrosive than those prepared with crude wood tar Creosote, being similar to the coal tar Creosote
Toshie Tsuchiya - One of the best experts on this subject based on the ideXlab platform.
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Monitoring of polycyclic aromatic hydrocarbons and water-extractable phenols in Creosotes and Creosote-treated woods made and procurable in Japan.
Chemosphere, 2005Co-Authors: Yoshiaki Ikarashi, Masa-aki Kaniwa, Toshie TsuchiyaAbstract:Abstract The recycling of disused railway sleepers treated with wood preservatives such as Creosote as exterior wood for use in gardens has recently become popular in Japan. Creosote contains high quantities of polycyclic aromatic hydrocarbons (PAHs), and can lead to skin irritation and disease. In this work we have determined the amount of PAHs and water-extractable phenols in Creosote and Creosote-treated wood products such as railway sleepers and stakes for agricultural use that are either made or are procurable in Japan. PAHs were extracted with dichloromethane and analyzed by gas chromatography–mass spectrometry. Among carcinogenic PAHs, benz( a )anthracene was detected in the highest concentration, varying between 228 and 6328 μg/g in Creosotes. Benzo( b )fluoranthene, benzo( k )fluoranthene and benzo( a )pyrene (BaP) were found in the range of 67–3541 μg/g. Almost all Creosotes contained more than 50 μg/g of BaP, which is the upper limit level that is permitted in the European Union (EU). Creosote-impregnated wood products, such as brand-new or secondhand railway sleepers and foundations, contained large amounts of BaP (58–749 μg/g) and benz( a )anthracene (250–1282 μg/g). Concentrations of between 692 and 2489 μg/g of phenols were determined in the water extracts from Creosotes, but the level was considerably less than the EU control value (3% by mass), and there was no correlation between the amount of water-extractable phenols and the amount of PAHs detected in each sample. The situation that consumers are free to use the Creosotes containing a high concentration of carcinogens such as BaP may cause unacceptable damage to the health of persons handling these Creosote products.
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Determination of Benzo[a]pyrene, Benz[a]anthracene and Dibenz[a,h]anthracene in Creosotes and Creosote-Treated Woods
Journal of Health Science, 2005Co-Authors: Yoshiaki Ikarashi, Masa-aki Kaniwa, Toshie TsuchiyaAbstract:The amount of benzo[a]pyrene (BaP), benz[a]anthracene (BaA), and dibenz[a,h]anthracene (DBA) has been restricted to a concentration of 10 g/g each in Creosotes, and 3 g/g each in Creosote-treated woods, respectively, because of the possibility of the risk of skin cancer in consumers, and Creosotes can otherwise contain high concentrations of each chemical. We already reported the content of 16 polycyclic aromatic hydrocarbons (PAHs) and phenols in Creosotes and Creosote-treated wood as determined by gas chromatography-mass spectrometry (GC-MS) and absorptiometry [Chemosphere, 60, 1279–1287 (2005)]. However, the limit of determination of each PAH per sample was > 40 g/g according to that method, the sensitivity of which was insufficient for determining the allowable levels of these 3 compounds. Moreover, a substantial amount of time was needed for GC-MS analysis. In the present study, we improved upon our previous analytical method in order to increase the sensitivity of the test and to reduce the duration of GC-MS analysis. Creosote was extracted from treated wood samples by dichloromethane-soak incubation, and was placed on a Sep-Pak silica cartridge and eluted with dichloromethane. The eluates were evaporated and dissolved in dichloromethane. The sample solution spiked with the internal standard solution was injected into the GC-MS system. The limit of determination of each chemical in the test solution was approximately 0.2 g/ml, which corresponded to 1–2 g/g in each sample. The duration of GC-MS analysis was approximately 17 min. A collaborative study was also carried out in order to evaluate the reproducibility of the method for determining low levels of BaP and related compounds in Creosotes. The present method was applied for the analysis of certain commercially available Creosotes and Creosote-treated wood samples in Japan. It was confirmed that some Creosotes and railway sleepers contained these compounds in high concentrations, thus exceeding the allowed control value.