Chemical speciation and bioaccessibility of arsenic and chromium in chromated copper arsenate-treated wood and soils

This research compares the As and Cr chemistry of dislodgeable residues from chromated copper arsenate (CCA)-treated wood collected by two different techniques (directly from the board surface either by rubbing with a soft bristle brush or by rinsing from human hands after contact with CCA-treated wood) and demonstrates that these materials are equivalent in terms of both the chemical form and bonding of As and Cr and in terms of the As leaching behavior. This finding links the extensive chemical characterization and bioavailability testing that has been done previously on the brush-removed residue to a material that is derived from human skin contact with CCA-treated wood. Additionally, this research characterizes the arsenic present in biological fluids (sweat and simulated gastric fluid) following contact with these residues. The data demonstrate that in biological fluids the arsenic is present primarily as free arsenate ions. Arsenic-containing soils were also extracted into human sweat to evaluate the potential for arsenic dissolution from soils at the skin surface. For soils from field sites, only a small fraction of the total arsenic is soluble in sweat. Based on comparisons to reference materials that have been used for in vivo dermal absorption studies, these findings suggest that the actual relative bioavailability via dermal absorption of As from CCA residues and soil may be well below the current default value of 3% used by U.S. EPA.     

Release of arsenic to the environment from CCA-treated wood. 1. Leaching and speciation during service

Insufficient information exists about the speciation of arsenic leaching from in-service chromated copper arsenate (CCA)-treated products and the overall impact to soils and groundwater. To address this issue, two decks were constructed, one from CCA-treated wood and the other from untreated wood. Both decks were placed in the open environment where they were impacted by rainfall. Over a one-year period, rainwater runoff from the decks and rainwater infiltrating through 0.7 m of sand below the decks was collected and analyzed for arsenic species by HPLC-ICP-MS. The average arsenic concentration in the runoff of the untreated deck was 2-3 microg/L, whereas from the CCA-treated deck it was 600 microg/L. Both inorganic As(III) and As(V) were detected in the runoff from both decks, with inorganic As(V) predominating. No detectable levels of organoarsenic species were observed. The total arsenic concentration in the infiltrated water of the treated deck had risen from a background concentration of 3 microg/L to a concentration of 18 microg/L at the end of the study. Data from the deck study were combined with annual CCA-treated wood production statistics to develop a mass balance model to estimate the extent of arsenic leaching from in-service CCA-treated wood structures to Florida soils. Results showed that during the year 2000, of the 28 000 t of arsenic imported into the state and utilized for in-service CCA-treated wood products, approximately 4600 t had already leached. Future projections suggest that an additional 11,000 t of arsenic will leach during in-service use within the next 40 years.     

Arsenic speciation of solvent-extracted leachate from new and weathered CCA-treated wood

For the past 60 yr, chromate-copper-arsenate (CCA) has been used to pressure-treat millions of cubic meters of wood in the United States for the construction of many outdoor structures. Leaching of arsenic from these structures is a possible health concern as there exists the potential for soil and groundwater contamination. While previous studies have focused on total arsenic concentrations leaching from CCA-treated wood, information pertaining to the speciation of arsenic leached is limited. Since arsenic toxicity is dependent upon speciation, the objective of this study was to identify and quantify arsenic species leaching from new and weathered CCA-treated wood and CCA-treated wood ash. Solvent-extraction experiments were carried out by subjecting the treated wood and the ash to solvents of varying pH values, solvents defined in the EPA's Synthetic Precipitation Leaching Procedure (SPLP) and Toxicity Characteristic Leaching Procedure (TCLP), rainwater, deionized water, and seawater. The generated leachates were analyzed for inorganic As(III) and As(V) and the organoarsenic species, monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA), using high-performance liquid chromatography followed by hydride generation and atomic fluorescence spectrometry (HPLC-HG-AFS). Only the inorganic species were detected in any of the wood leachates; no organoarsenic species were found. Inorganic As(V) was the major detectable species leaching from both new and weathered wood. The weathered wood leached relatively more overall arsenic and was attributed to increased inorganic As(III) leaching. The greater presence of As(III) in the weathered wood samples as compared to the new wood samples may be due to natural chemical and biological transformations during the weathering process. CCA-treated wood ash leached more arsenic than unburned wood using the SPLP and TCLP, and ash samples leached more inorganic As(III) than the unburned counterparts. Increased leaching was due to higher concentrations of arsenic within the ash and to the conversion of some As(V) to As(III) during combustion.     

Release of arsenic to the environment from CCA-treated wood. 2. Leaching and speciation during disposal

Wood treated with chromated copper arsenate (CCA) is primarily disposed within construction and demolition (C&D) debris landfills, with wood monofills and municipal solid waste (MSW) landfills as alternative disposal options. This study evaluated the extent and speciation of arsenic leaching from landfills containing CCA-treated wood. In control lysimeters where untreated wood was used, dimethylarsinic acid (DMAA) represented the major arsenic species. The dominant arsenic species differed in the lysimeters containing CCA-treated wood, with As(V) greatest in the monofill and C&D lysimeters and As(III) greatest in the MSW lysimeters. In CCA-containing lysimeters, the organoarsenic species monomethylarsonic acid (MMAA) and DMAAwere virtually absent in the monofill lysimeter and observed in the C&D and MSW lysimeters. Overall arsenic leaching rate varied for the wood monofill (0.69% per meter of water added), C&D (0.36% per m), and MSW (0.84% per m) lysimeters. Utilizing these rates with annual disposal data, a mathematical model was developed to quantify arsenic leaching from CCA-treated wood disposed to Florida landfills. Model findings showed between 20 and 50 t of arsenic (depending on lysimeter type) had leached prior to 2000 with an expected increase between 350 and 830 t by 2040. Groundwater analysis from 21 Florida C&D landfills suspected of accepting CCA-treated wood showed that groundwater at 3 landfills was characterized by elevated arsenic concentrations with only 1 showing impacts from the C&D waste. The slow release of arsenic from disposed treated wood may account for the lack of significant impact to groundwater near most C&D facilities at this time. However, greater impacts are anticipated in the future given that the maximum releases of arsenic are expected by the year 2100.     

Emissions of chromium, copper, arsenic, and PCDDs/Fs from open burning of CCA-treated wood

Aged and weathered chromated copper arsenate (CCA) treated wood was burned in an open burn research facility to characterize the air emissions and residual ash. The objectives were to simulate, to the extent possible, the combustion of such waste wood as might occur in an open field or someone's backyard; to characterize the composition and particle size distribution (PSD) of the emitted fly ash; to determine the partitioning of arsenic, chromium, and copper between the fly ash and residual ash; and to examine the speciation of the CCA elements. This work reports preliminary air emission concentrations and estimated emission factors for total particulate matter, arsenic (As), chromium (Cr), copper (Cu), and polychlorinated dibenzodioxins/dibenzofurans (PCDD/F) totals and toxic equivalents (TEQs). The partitioning of As, Cr, and Cu between the emitted fly ash and residual ash is examined and thermochemical predictions from the literature are used to explain the observed behavior. Results indicate a unimodal fly ash PSD between 0.1 and 1.0 microm diameter. In addition to a large carbonaceous component, between 11 and 14% of the As present in the burned CCA treated wood was emitted with the air emissions, with the remainder present in the residual ash. In contrast, less than 1% of both the Cr and Cu present in the wood was emitted with the air emissions. PCDD/F levels were unremarkable, averaging 1.7 ng TEQ/kg of treated wood burned, a value typical for wood combustion. Scanning electron microscopy (SEM) was unable to resolve inorganic particles consisting of Cu, Cr, or As in the wood samples, but X-ray absorption fine structure (XAFS) spectroscopy confirmed that the oxidation states of the CCA elements in the wood were Cu2+, Cr3+, and As5+. SEM examination of the fly ash samples revealed some inorganic microcrystals within the mostly carbonaceous fly ash, while XAFS spectroscopy of the same samples showed that the oxidation states after combustion were mixed Cu+ and Cu2+, Cr3+, and mixed As3+ and As5+. Estimates of the ratios of the mixed oxidation states based on the XAFS spectra were As3+/(total As) = 0.8-0.9 and Cu+/(total Cu) = 0.65-0.7. The Cu and Cr present in the fly ash were determined to coexist predominantly in the two oxide phases CuCrO2 and CuCr2O4. These results indicate that the open burning of CCA-treated wood can lead to significant air emissions of the more toxic trivalent form of As in particle sizes that are most respirable.     

In vitro gastrointestinal bioavailability of arsenic in soils collected near CCA-treated utility poles

Because of the potentially high arsenic concentrations found in soils immediately adjacent to chromated copper arsenate (CCA)-treated wood structures and utility poles, CCA-contaminated soil ingestion may be a significant exposure route to arsenic for children. Therefore, a strong need exists to provide accurate data on oral relative bioavailability (RBA) of arsenic (in vivo or in vitro) in field-collected CCA-contaminated soils. The objectives of this study were (1) to assess arsenic bioaccessibility in contaminated soils collected near in-service CCA-treated utility poles, (2) to determine the influence of soil properties and arsenic fractionation on arsenic bioaccessibility, and (3) to estimate an average daily arsenic intake from incidental soil ingestion. Arsenic bioaccessibility (in vitro gastrointestinal (IVG) method) was determined on surface soil samples collected immediately adjacent to 12 CCA-treated utility poles after 18 months of service. Bioaccessible arsenic was also determined in 3 certified reference materials. Total arsenic concentrations in soils (<300 microm) varied from 37 +/- 2 to 251 +/- 12 mg/kg, irrespective of soil organic matter contentwith the major soil-bound arsenic species being As(V). Arsenic bioaccessibility ranged between 25.0 +/- 2.7 and 66.3 +/- 2.3% (mean value 40.7 +/- 14.9%). The mean value was in agreement with the in vivo arsenic RBA reported by Casteel et al. (2003) in soil near CCA-treated utility poles. Bioaccessible arsenic was positively correlated with total organic carbon content (r2 = 0.36, p < 0.05) and with water-soluble arsenic (2 = 0.51, p < 0.01), and was negatively correlated with clay content (r2 = 0.43, p < 0.05). Using conservative exposure parameters, the mean daily arsenic intake from incidental ingestion of contaminated soil near CCA-treated utility poles was 0.18 +/- 0.09 microg As kg(-1) d(-1). This arsenic intake appeared negligible compared to the daily intake of inorganic arsenic from water and food ingestion for children.     

Effect of simulated rainfall and weathering on release of preservative elements from CCA treated wood

The release of arsenic from wood pressure-treated with chromated copper arsenate (CCA) can be decreased by application of wood finishes, but little is known about the types of finishes that are best suited for this purpose. This study evaluated the effects of finish water repellent content and ultraviolet (UV) radiation on the release of arsenic, copper, and chromium from CCA-treated wood exposed to simulated rainfall. Deck boards treated with CCA were either left unfinished or dipped in a finish prepared with 1%, 3%, or 5% water repellent. All specimens were exposed to leaching from simulated rainfall, and a subset of specimens was also exposed to UV radiation. The rainfall was collected and analyzed for total elemental arsenic, copper, and chromium. The water repellent significantly decreased the amounts of these elements in the runoff, but for the short duration of this study there was no difference among the three water repellent concentrations. It is possible that water repellent content would have a greater effect over a longer exposure period. Exposure to UV radiation caused a significant increase in leaching from both finished and unfinished specimens. This effect may be a result of increased surface area during weathering as well as loss of fibers caused by UV-induced surface erosion.     

Arsenic and chromium partitioning in a podzolic soil contaminated by chromated copper arsenate

This research combined the use of selective extractions and X-ray spectroscopyto examine the fate of As and Cr in a podzolic soil contaminated by chromated copper arsenate (CCA). Iron was enriched in the upper 30 cm due to a previous one-time treatment of the soil with Fe(II). High oxalate-soluble Al concentrations in the Bs horizon of the soil and micro-XRD data indicated the presence of short-range ordered aluminosilicates (i.e., proto-imogolite allophane, PIA). In the surface layers, Cr, as Cr(III), was partitioned between a mixed Fe(III)/ Cr(III) solid phase that formed upon the Fe(II) application (25-50%) and a recalcitrant phase (50-75%) likely consisting of organic material such as residual CCA-treated wood. Deeper in the profile Cr appeared to be largely in the form of extractable (hydr)oxides. Throughout the soil, As was present as As(V). In the surface layers a considerable fraction of As was also associated with a recalcitrant phase, probably CCA-treated woody debris, and the remainder was associated with (hydr)oxide-like solid phases. In the Bs horizon, however, XAS and XRF findings strongly pointed to the presence of PIA acting as an effective adsorbent for As. This research shows for the first time the relevance of PIA for the adsorption of As in natural soils.     

Arsenic leaching from mulch made from recycled construction and demolition wood and impacts of iron-oxide colorants

Mulch made from recycled construction and demolition (C&D) wood has been reported to contain elevated levels of arsenic from inadvertent inclusion of chromated copper arsenate (CCA)-treated wood. Such mulch is also commonly colored with iron oxide, a compound known to bind arsenic. The objectives of this study were to quantify the releases of arsenic from mulch made from C&D wood, to evaluate the impacts of an iron-oxide colorant in potentially decreasing arsenic leaching rates, and to evaluate the relative significance of additional variables on leachate concentrations. Atotal of 3 sets of mulch samples (0%, 5%, or 100% CCA-treated wood) were prepared containing a sample either with or without colorant addition. Each sample was subjected to two tests: a field leaching test and the Synthetic Precipitation Leaching Procedure (SPLP). Results showed that arsenic concentrations in the field leachate from the 0% treated wood mulches were consistently low (<0.003-0.013 mg/L) whereas leachates from 5 and 100% treated wood mulches were characterized by higher arsenic concentrations (0.059-2.23 mg/L for 5%; 0.711-22.7 mg/L for 100%). The mass of arsenic leached from the field samples during the 1-year monitoring period was between 10 and 15% of the initial mass of arsenic. The colorant reduced the leaching of arsenic by more than 20% for the field leachate and 50% for the SPLP leachate, on average. However, the study showed that the effect may not last for long periods. Besides colorant addition other factors were observed to affect the amount of arsenic leached from contaminated mulch. These include the proportion of CCA-treated wood in the mulch, time, and pH of rainfall.     

Relative leaching and aquatic toxicity of pressure-treated wood products using batch leaching tests

Size-reduced samples of southern yellow pine dimensional lumber, each treated with one of five different waterborne chemical preservatives, were leached using 18-h batch leaching tests. The wood preservatives included chromated copper arsenate (CCA), alkaline copper quaternary, copper boron azole, copper citrate, and copper dimethyldithiocarbamate. An unpreserved wood sample was tested as well. The batch leaching tests followed methodology prescribed in the U.S. Environmental Protection Agency toxicity characteristic leaching procedure (TCLP). The wood samples were first size-reduced and then leached using four different leaching solutions (synthetic landfill leachate, synthetic rainwater, deionized water, and synthetic seawater). CCA-treated wood leached greater concentrations of arsenic and copper relative to chromium, with copper leaching more with the TCLP and synthetic seawater. Copper leached at greater concentrations from the arsenic-free preservatives relative to CCA. Arsenic leached from CCA-treated wood at concentrations above the U.S. federal toxicity characteristic limit (5 mg/L). All of the arsenic-free alternatives displayed a greater degree of aquatic toxicity compared to CCA. Invertebrate and algal assays were more sensitive than Microtox. Examination of the relative leaching of the preservative compounds indicated that the arsenic-free preservatives were advantageous over CCA with respect to waste disposal and soil contamination issues but potentially posed a greater risk to aquatic ecosystems.     

Arsen im Holzschutz

Arsenic compounds used in wood preservation are classified as dangerous substances for which a cancerogenic effect to man has clearly been shown. Occupational exposure is possible by working up the preservatives and the impregnated wood. In the area of preservation plants in part a tremendously high contamination of soil by arsenic has been measured. By modern technology the environmental input in the area of the preservation plant could be reduced to a large extent. Although wood impregnated with arsenicals is thought to be relatively safe during its use, considerable proportions of the arsenic from CCA-treated wood can be loaded onto the environment under severe leaching conditions. By burning treated wood without flue gas cleaning 20% to 80% of the arsenic will be emitted to the air. There the arsenic is again present in a form for which a cancerogenic potential has been shown. Waste management problems of treated wood are discussed from a legal, practical and environmental policy point of view, and other sources of emission of arsenic are referred to comparison.     

Arsen im Holzschutz

Arsenic compounds used in wood preservation are classified as dangerous substances for which a cancerogenic effect to man has clearly been shown. Occupational exposure is possible by working up the preservatives and the impregnated wood. In the area of preservation plants in part a tremendously high contamination of soil by arsenic has been measured. By modern technology the environmental input in the area of the preservation plant could be reduced to a large extent. Although wood impregnated with arsenicals is thought to be relatively safe during its use, considerable proportions of the arsenic from CCA-treated wood can be loaded onto the environment under severe leaching conditions. By burning treated wood without flue gas cleaning 20% to 80% of the arsenic will be emitted to the air. There the arsenic is again present in a form for which a cancerogenic potential has been shown. Waste management problems of treated wood are discussed from a legal, practical and environmental policy point of view, and other sources of emission of arsenic are referred to comparison.     

Landfill disposal of CCA-treated wood with construction and demolition (C&D) debris: arsenic, chromium, and copper concentrations in leachate

Although phased out of many residential uses in the United States, the disposal of CCA-treated wood remains a concern because significant quantities have yet to be taken out of service, and it is commonly disposed in landfills. Catastrophic events have also led to the concentrated disposal of CCA-treated wood, often in unlined landfills. The goal of this research was to simulate the complex chemical and biological activity of a construction and demolition (C&D) debris landfill containing a realistic quantity of CCA-treated wood (10% by mass), produce leachate, and then evaluate the arsenic, copper, and chromium concentrations in the leachate as an indication of what may occur in a landfill setting. Copper concentrations were not significantly elevated in the control or experimental simulated landfill setting (alpha = 0.05). However, the concentrations of arsenic and chromium were significantly higher in the experimental simulated landfill leachate compared to the control simulated landfill leachate (alpha = 0.05, p < 0.001). This indicates that disposal of CCA-treated wood with C&D debris can impact leachate quality which, in turn could affect leachate management practices or aquifers below unlined landfills.     

Anthropogenic sources of arsenic and copper to sediments in a suburban lake,Northern Virginia

Mass balances of total arsenic and copper for a suburban lake in densely populated northern Virginia were calculated using date collected during 1998. Mass-balance terms were precipitation; stream inflow, including road runoff; stream outflow; and contributions from leaching of pressure-treated lumber. More mass of arsenic and copper was input to the lake than was output the 1998 lake-retention rates were 70% for arsenic and 20% for copper. The arsenic mass balance compared well with a calculated annual mass accumulation in the top 1 cm of the lake sediments; however, the calculated contribution of copper to the lake was insufficient to account for the amount of copper in this zone. Leaching experiments were conducted on lumber treated with chromated copper arsenate (CCA) to quantify approximate amounts of arsenic and copper contributed by this source. Sources to lake sediments included leaching of CCA-treated lumber (arsenic, 50%; copper, 4%), streamwater (arsenic, 50%; copper, 90%), and atmospheric deposition (arsenic, 1%; copper, 3%). Results of this study suggest that CCA-treated lumber and road runoff could be significant nonpoint sources of arsenic and copper, respectively, in suburban catchments.     

Bioremediation of CCA-C treated wood by Aspergillus niger fermentation

This study evaluated the potential of the fungus Aspergillus niger to remove copper, chromium, and arsenic from waste wood treated with chromated copper arsenate (CCA) wood preservative. The removal of heavy metals by A. niger was carried out in two stages. In the first stage, A. niger was cultivated in carbohydrates media in order to produce large quantities of oxalic acid. Bioremediation of CCA-treated wood was performed in the second stage through both leaching of heavy metals with oxalic acid occurred during the first stage and possible biosorption of metals onto the binding sites in the cellular structure of A. niger. Oxalic acid production by A. niger was 13.4 kg/m³ at pH 6 and in an enriched nitrogen and phosphorus medium. CCA-treated chips exposed to A. niger for 10 days showed a decrease in arsenic of 97%. In addition, A. niger fermentation removed 49% copper and 55% chromium from CCA-treated chips. This study showed that fungal fermentation and passive metal removal by A. niger had a potential in arsenic release from CCA-treated waste wood.

---

Aufwertung von CCA-behandeltem Holz durch Fermentation mit Aspergillus niger

Zusammenfassung Diese Studie untersuchte die Möglichkeit des Pilzes Aspergillus niger Kupfer, Chrom und Arsen von Abfallholz, das mit CCA-Holzschutzmittel behandelt worden war, zu entfernen. Die Entfernung von Schwermetallen durch A. niger wurde in zwei Stufen durchgeführt. Während der ersten Stufe wurde A. niger in Kohlenhydratmedien kultiviert, um große Mengen von Oxalsäure zu produzieren. Die Aufwertung von CCA-behandeltem Holz wurde während der zweiten Stufe durchgeführt. Sowohl das Auslaugen der Schwermetalle mit Oxalsäure als auch die mögliche Biosorption von Metallen an Rezeptoren in der Zellstruktur von A. niger fand während der ersten Stufe statt. Die Oxalsäure-Produktion durch A. niger betrug 13,4 kg/m³ bei einem pH-Wert 6 in einem mit Stickstoff und Phosphor angereichertem Medium. Die mit CCA behandelten Späne zeigten nach 10-tägiger Behandlung mit A. niger einen Arsenabfall von 97%. Zusätzlich entfernte die A. niger-Fermentation 49% Kupfer und 55% Chrom von CCA-behandelten Spänen. Diese Studie zeigte, dass Pilzfermentation und passive Metallentfernung durch A. niger eine Möglichkeit bot, Arsen von CCA-behandeltem Holz freizusetzen.

     

Fate of Cu, Cr, and As during combustion of impregnated wood with and without peat additive

The E.U. Directive on incineration of waste regulates the harmful emissions of particles and twelve toxic elements, including copper, chromium, and arsenic. More information is critically needed on the speciation and behavior of these trace elements during combustion, including the effects of different process variables, as well as of different fuels and fuel mixtures. Using a 15 kW pellets-fueled grate burner, experiments were performed to determine the fate of copper, chromium, and arsenic during combustion of chromate copper arsenate (CCA) preservative wood. The effects of co-combustion of CCA-wood with peat were also studied since peat fuels previously have proved to generally reduce ash related problems. The fate and speciation of copper, chromium, and arsenic were determined from analysis of the flue gas particles and the bottom ash using SEM-EDS, XRD, XPS, and ICP-AES. In addition, chemical equilibrium model calculations were performed to interpret the experimental findings. The results revealed that about 5% copper, 15% chromium, and 60% arsenic were volatilized during combustion of pure CCA-wood, which is lower than predicted volatilization from the individual arsenic, chromium, and copper oxides. This is explained by the formation of more stable refractory complex oxide phases for which the stability trends and patterns are presented. When co-combusted with peat, an additional stabilization of these phases was obtained and thus a small but noteworthy decrease in volatilization of all three elements was observed. The major identified phases for all fuels were CuCrO2(s), (Fe, Mg, Cu)(Cr, Fe, Al)04(s), Cr2O3(s), and Ca3(AsO4)2(s). Arsenic was also identified in the fine particles as KH2AsO4(s) and As2O3(s). A strong indication of hexavalent chromium in the form of K2CrO4 or as a solid solution between K3Na(CrO4)2 and K3Na(SO4)2 was found in the fine particles. Good qualitative agreement was observed between experimental data and chemical equilibrium model calculations.     

Extraction of hexavalent chromium from chromated copper arsenate treated wood under alkaline conditions

Information on chromium (Cr) oxidation states is essential for the assessment of environmental and health risks associated with the overall life-cycle of chromated copper arsenate (CCA) treated wood products because of differences in toxicity between trivalent [Cr(III)] and hexavalent [Cr(VI)] chromium compounds. Hypothetical Cr(VI) fixation products were investigated in CCA type C treated sawdust of aspen and red pine during or following preservative fixation by extraction with Cr(VI)-specific extractants. Cr(VI) was found only in alkaline extracts of treated wood. A major source of Cr(VI) was method-induced oxidation of fixed Cr(III) during alkaline extraction, as confirmed by demonstrated oxidation of Cr(III) from CrCl3 treated wood. Oxidation of nontoxic and immobile Cr(III) to toxic and mobile Cr(VI) was facilitated by the presence of wood at pH > 8.5. Thermodynamic equilibrium between Cr(III) and Cr(VI) is affected by pH, temperature, rates of dissolution of CrIII) compounds, and oxygen availability. Results of this study recommend against alkaline extraction protocols for determination of Cr(VI) in treated wood. This Cr oxidation mechanism can act as a previously unrecognized route for generation of hazardous Cr(VI) if CCA treated wood is exposed to alkaline conditions during its production, use, or waste management.     

Arsenic and other trace elements in wines of eastern Croatia

Levels of arsenic and other trace elements (Al, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sb, Se, Sn, Sr, Ti, Tl, U, V and Zn) in nine brands of wine from Slavonia (eastern Croatia) were investigated. Wines from two other viticulture areas, Istria (western Croatia) and Vojvodina (northern Serbia), were used for comparison. Elemental concentrations were determined by high resolution ICP-MS. Statistical methods were applied for the interpretation of obtained data. Regional differences were identified based on a set of geogenic elements (Al, Li, Be, Ti). Elements As and Pb were found to be of predominantly natural origin. Significant differences between the obtained values for As in wines from Slavonia and Vojvodina, compared to wines from Istria indicate that the geochemical arsenic anomalies present in these regions contribute to some extent to higher As content in analysed wines. The Cd, Ni, Zn, Fe and Cr in wine were found to be primarily of anthropogenic origin.     

Arsen im Holzschutz

Arsenic in wood preservation is used all over the world mainly in Copper-Chrome-Arsenic (CCA) wood preservatives by pressure treatment. In the Federal Republic of Germany this use for outdoor wood is not yet forbidden as an exception of a comprehensive ban of the use of arsenical compounds. This regulation originates primarily from an EEC directive. Arsenic content of the CCA salts varies between 11% and 29%, the most common retention is 6 kg salt per m³ of the total volume of treated wood. In the FRG CCA salts are not produced anymore and are used to a relative low extent yet. Although there seems to be a declining trend towards the import of wood treated with arsenicals, in 1988 still approximately 100–200 t of arsenic were introduced to the FRG by this way.     

筷子涂层中重金属元素的暴露研究

目的研究筷子涂层中12种重金属元素(锌、铜、镍、镉、铅、汞、铬、钼、硒、砷、钡、锑)在体液模拟物和食品模拟物中的暴露。方法以胃液模拟物、唾液模拟物作为体液模拟物,以4%乙酸(V/V)、水、95%乙醇(V/V)作为食品模拟物,利用电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法测定筷子涂层中12种重金属元素的溶出量和迁移量。结果对20批次筷子涂层中12种重金属元素的含量进行测试发现10种重金属元素(锌、铜、镍、镉、铅、铬、钼、硒、砷、钡)有检出,其中铅元素含量高达347660.8mg/kg。对检出的重金属元素进一步分析其在体液模拟物中的溶出量和食品模拟物中的迁移量,发现高含量的元素能通过体液模拟物溶出和食品模拟物迁移。结论筷子涂层中重金属元素可能通过3种途径暴露至人体,分别是胃液溶出、唾液溶出、食品中迁移,且涂层涂覆的位置可对重金属元素的暴露途径产生影响;胃液模拟物中溶出量是唾液模拟物中溶出量的10倍以上;4%乙酸(V/V)食品模拟物中的迁移量最多可高于水和95%乙醇(V/V)食品模拟物中的迁移量近1000倍,且随着迁移次数的增加迁移量逐渐降低。