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Determination of the preventive efficacy against wood destroying basidiomycetes fungi, EN V 839 - CEN/TC 38 WG 9
1993 - IRG/WP 93-20015
The WG 9 of CEN TC/38 has presented to EC a mycological test to assess efficacy of preservatives applied by surface process. This method is now an experimental standard (EN V 839) which has to be approved by the different european delegations. The following paper is not the standard as it has been proposed but is a presentation of the principle of the method. The experimental standard specifies a laboratory method of test which gives a basis of the assessment of the preventive action of a wood preservative when applied as a surface treatment against Basidiomycetes fungi. This method is applicable to formulations of preservatives in a ready to use form (organic formulations, organic water-dispersible formulations, water-soluble materials). Series of susceptible wood species specimens are treated on longitudinal faces whith the preservative in test using brushing as surface procedure. Test specimens are then exposed by an intermediate mesh to feeder blocks infestedby pure culture of Basidiomycetes fungi in sterile conditions and penetration of fungi is assessed on cross section sawn in the samples at the end of the test.
D Dirol


On site test for indicative determination of leaching of components of preservatives from treated timber. Part 2: New data on CCA-C, CC and CCB treated timber
1994 - IRG/WP 94-50025
The 'on site test' was published at the IRG meeting in Cannes in February 1993 (IRG/WP 93-50001/12). Since this publication many on site tests were performed parallel to so-called shower tests. The correlation between the test results of the on site tests and the shower test has been established more clearly. For chromium the correlation between both tests is indistinctive of preservative formulation. For copper the correlation differs for CCA on one side and CC's and CCB's on the other side. In some cases the on site test does not correcty predict shower test results. The reasons for this phenomenon are discussed. It can be concluded that the on site test is a roughly indicative test for assessing the leaching of components of preservatives from treated timber. The correlation figures, however, are formulation dependent.
W J Homan


Quantitative determination of Chromium: A comparison of three instruments
1995 - IRG/WP 95-50053
A comparison is made between three instruments for measuring levels of chromium in the leachate of copper-chrome-arsenic (CCA) treated timber. These include an atomic absorption spectrophotometer, an inductively coupled plasma spectrometer and the RQflexâ. The RQflexâ is a new hand-held instrument which measures chromium by dipping a ReflectoquantÒ strip into the leachate and inserting the strip into the RQflexâ. Readings are determined reflectometrically following a reaction between chrome and the Reflectoquantâ strip. It provides an inexpensive and quick technique which is used in this paper to determine the degree of preservative fixation prior to the removal of CCA treated timber from drip pads of wood treatment sites. The results indicate that RQflexâ is a suitable instrument for the rapid assessment of chromium levels in rain wash off from treated timber. A comparison is given of the economics and accuracy of the instruments for measuring chromium.
S Walley, P R S Cobham, P Vinden


A standardised procedure for the treatment of timber with test chemicals
1986 - IRG/WP 2257
A procedure is described which allows the standardisation of sample handling and data manipulation during trials invastigating the treatability of timber with test chemicals. The use of computer software allows the data to be handled efficiently.
J Norton, A Zosars, L E Leightley


Statistically stable models for determination of PEC
1999 - IRG/WP 99-50135
In June 1998 the European Wood Preservative Manufacturer's Group prepared a document to support the Technical Guidance concerning the placing of products on the market with respect to the Directive 98/08/EC (BPD). The essentials of this document were presented at the COST E2 meeting in Cannes last year and at the following IRG conference (Baines and Davis, 1998; IRG/WP/98-50101/20). The document presented a protocol in which a "tiered" approach is followed. The key-factors in this approach are the PNEC (predicted no effect concentration) and the PEC (predicted environmental concentration). The PNEC is calculated from eco-toxicity test results and a safety factor is introduced. In the case of metals which may also be essential trace elements, the background level is suggested as the PNEC, if this level is above the level derived f rom eco-toxicity tests. The calculation of the PEC uses different models. The focus of this paper is the reliability of the models used to determine the PEC, while pointing out that only data and models relevant to the field situation may be used. In the EWPM protocol, initially the environment has to be defined by going through flowcharts and providing an answer of "YES or NO" to each of the questions. In the first tier of the questions there are two options for the treated wood, which is likely to be treated with the candidate wood preservative. It can be assessed as presenting either: a) No risk to the environment, or b) Additional information is required and the next "tier" of questions or tests is involved. In this paper the model for a fresh water environment is presented as an example. However, the models and the systern, can also be applied to other environments. In the above mentioned flowcharts the following assumptions are made: 1.Yes, the substance is toxic and harmful, 2. Yes, if all of the substance in the treated wood entered the water, its concentration would probably be > the PNEC, 3. Yes, the treated wood is in a situation where some of the substance is likely to get into the water. For this reason a simulated exposure test would be carried out and: 4. Yes, the chemical analysis of the wash-off water would be possible and relevant. Therefore PECwater values would need to be calculated to solve the question whether PECwater> PNECwater. By definition, the PEC must be based on the same principle as the PNEC. This implies that the PEC must be relevant for long term exposition, as the PNEC is a long term value, derived from chronic studies.
W J Homan, A L Van Oosten Van


Determination of toxic limits of wood preservatives towards wood-destroying Basidiomycetes. Investigation on the effect of the use of two impregnated wood blocks and of one impregnated and an untreated block respectively in Kolle jars on the toxic limits of wood preservatives
1973 - IRG/WP 225
O Wälchli


Laboratory determination of the natural decay resistance of some lesser-utilized timbers from Tanzania against wood decay fungi
2004 - IRG/WP 04-10517
Four lesser known/utilized timber species (sap and heartwoods) from Tanzania, namely Albizia lebbeck, Zanthoxylum gilletii, Faurea saligna and Parinari curatellifolia were exposed to the brown rot fungi (Gloeophyllum trabeum and Coniophora puteana) and the white rot fungus (Coriolus versicolor) to determine their natural decay resistance according to the EN 113 standard procedure. The timbers were also ranked into natural durability classes according to EN 350-1. Albizia lebbeck, Faurea saligna and Parinari curatellifolia timber species (heartwood) were found to be very resistant while Zanthoxylum gilletii was heavily decayed by all the fungi. The durability ratings of the timbers were; Albizia lebbeck (1), Faurea saligna (1), Parinari curatellifolia (1) and Zanthoxylum gillettii (5). It is suggested that the durable timbers, Albizia lebbeck, Faurea saligna and Parinari curatellifolia should be promoted as alternatives to the well known durable timber species in Tanzania such as Tectona grandis, Afzelia quanzensis, Blachylaena hutchinsii and Pterocarpus angolensis which are currently being over-exploited.
P R Gillah, R C Ishengoma, E Julias, S A Amartey, D H Kitojo


Determination of total fluoride in preservative-treated wood by ion selective electrode, without steam distillation
1996 - IRG/WP 96-20086
An analytical method was developed to determine total fluoride in wood treated with aqueous fluoride or borate-fluoride formulations. Ground wood was mixed with 60% sodium hydroxide solution and oven-dried overnight before furnacing at 600°C. The cool fused product was dissolved in warm water before adding a powerful complexant/buffer solution containing sulphosalicylic acid and EDTA. Fluoride was measured by ion-selective electrode (ISE) against appropriately matrix-matched calibration standards containing 1, 10, or 100 ppm F. The method compared favourably with two alternatives; one employed the time-consuming distillation step included in the AWPA A2 1994 method, with a titration finish, and the second employed a double fusion and ISE finish, using TISAB buffer. The chosen buffer system exhibited better capacity than TISAB to complex excesses of model interferant Al. B and Si were also accommodated. Recovery from spiked Eucalyptus maculata (at 0.05-0.5% m/m F) was 94-96%. Precision when analysing Alstonia scholaris containing 0.35% m/m F was about 2%. The method enables better throughput than the AWPA A2 94 method
M J Kennedy


Cuticular hydrocarbons for species determination of tropical termites
1990 - IRG/WP 1465
Insect species have unique mixtures of cuticular hydrocarbons in the protective wax of their integument. We use hydrocarbons to evaluate similarities among termite populations. Our assumption is that colonies with similar hydrocarbon profiles are closely related. We have collected Reticulitermes in California from areas suspected to have only Reticulitermes hesperus or Reticulitermes tibialis. Their hydrocarbon profiles are similar but different. Colonies of "Reticulitermes tibialis" from distant locations in Arizona have profiles which are extremely different from Reticulitermes hesperus. This implies that there are at least 3 species of Reticulitermes in western North America when only two are described. The Formosan subterranean termite, Coptotermes formosanus, in the United States show no qualitative differences among four geographically distant populations; quantitative differences in hydrocarbon components separate them into different concentration profiles. Our results suggest that Coptotermes formosanus colonies from Florida and Louisiana are not closely related to those from Hawaii. We strongly suspect that the Coptotermes formosanus was introduced into Louisiana at least twice. Hydrocarbon profiles of Coptotermes formosanus from North America and Hawaii are different from Coptotermes from northern Australia, Southeast Asia and the Caribbean. Nasutitermes costalis and Nasutitermes ephratae were collected from five locations in Trinidad. Sixteen major hydrocarbon components were identified; all but one component were common to both species. Nasutitermes costalis has tremendous quantities of 13,17-dimethylhentriacontane whereas in Nasutitermes ephratae this hydrocarbon is insignificant. Furthermore, 12,16-dimethyltriacontane is completely missing in Nasutitermes ephratae. Nasutitermes costalis from Trinidad and Nasutitermes corniger from Panama appear to have cuticular hydrocarbon profiles that are more similar to one another than are those of Nasutitermes ephratae from Trinidad and Panama.
M I Haverty, M Page, B L Thorne, P Escoubas


Determination of physical properties of wood by Novel Guide
2006 - IRG/WP 06-40345
In empirical and theoretical determination of physical properties of wood, a schematic guide has been developed (as a novel guide) for the purpose of bringing facilities to researchers with a processing quantity in terms of data compilation. In this article physical properties of wood have been briefly described in respect to their effect on impregnation process, and technical information has been provided on usage of novel guide.
I Usta, M D Hale


The reliability of colouring methods for the determination of biflourides and boron in spruce wood
1994 - IRG/WP 94-20036
From practical reasons, qualitative spraying methods are widely used for the detection of bifluorides and boron in wood. The main aim of this research was to detect whether the concentration of the active ingredient in the coloured area is equal or greater than the toxic value against basidiomycetes. Both colouring methods, Z-A reagent for fluorides and curcuma reagent for boric acid, are a reliable means for the determination of the toxic threshold value, (found in literature) against basidiomycetes in spruce wood. Quantitatively, for fluorides the Eriochromocyaninezirkoniumoxidchloride method (DIN 52161 part 4) and for boron the mannitol - azomethine method (Peylo, 1993; Merck, 1989) are easy to perform and accurate
R Grell, M G Sanders, W J Homan, H Militz


Determination of fixation properties by bioassays - A proposal for the assessment of safety indexes in wood protection
1990 - IRG/WP 3566
In the determination of environmental effects of chemicals tests with fishes, daphnia and algae have proved to be practicable. With respect to wood protection such bioassays are suitable to control effects of treated timber against aquatic organisms. By using the fish-acute-toxicity-test the development of a laboratory test method is described for the checking of the fixation rate of a copper-chromium wood preservative. By this the importance of the observation of a proper fixation period is demonstrated for the use of treated wood in water contact. Estimating ecotoxicological effects of leachable compounds using sensitive bioindicators allows a differentiated determination of environmental risks of impregnated timber. The comparison with the toxic effects of the compounds of a wood preservative are a first step in the assessment of safety indexes in wood protection.
H-W Wegen


Development of a turbidity method for the determination of water repellent in CCA treatment solutions
2000 - IRG/WP 00-40177
The use of aqueous water repellent emulsion formulations has increased significantly in the wood treatment industry. These are primarily used to enhance the weathering characteristics of wood products treated with water borne preservatives systems used in exterior above ground exposures. However, they are also used in pole treatments to improve the climbing characteristics and in low VOC millwork treatments. With the increase in water repellent treated wood production there was a requirement to develop analytical methods for the determination of the water repellent concentration in treatment solutions for quality control at wood treatment facilities. Various methods were examined for the determination of water repellent emulsions in wood treatment solutions. Of the methods considered the turbidity method was found the best suited for routine quality control at treated wood production facilities. The effects of emulsion concentration and particle size on the turbidity measurements were evaluated.
P J Walcheski, L Jin


A comparison of inductively coupled plasma spectroscopy and neutron activity analysis for the determination of concentrations in wood
1993 - IRG/WP 93-10048
As wood decays the ionic composition changes, with increases often being seen in the concentrations of Ca, Mg, Fe, Mn and sometimes K. The concentration of eight cations in red spruce sapwood and heartwood samples was determined independently by inductively coupled plasma spectroscopy (ICP) and by neutron activation analysis (NAA) as part of an effort to standardize our analytical procedures and create a uniform wood standard for use by multiple researchers. Preliminary studies indicate a difference in the values of Ca and K as estimated by ICP and NAA, possibly due to a loss of these elements due to volatilization during ashing.
J Jellison, J Connolly, K C Smith, W T Shortle


ATP assay for the determination of mould activity on wood at different moisture conditions
1992 - IRG/WP 92-2397
To determine fungal responses to fungicides and environmental conditions and for detection of microbial activity in wood, sensitive and objective methods are needed. We have developed a suitable assay based on analysis of adenosine triphosphate (ATP) by using the luciferin-luciferase reaction. With the aid of this assay the activity of Penicillium brevicompactum on wood at different RH levels was studied. The ATP content in a two week old culture responded quite rapidly to changes in humidity. The ATP content in the colony moved to 70% or lower RH for one week was 10 times lower than the ATP content in the colony kept at 100% relative humidity for the same time period. Increasing the humidity level to 100% RH one week before the ATP determination from a period at lower humidities did not result in a significant increase in the ATP content. This probably indicates that the mycelia of the fungus did not survive the low humidity treatment.
J Bjurman


Longterm monitoring of termite activity on multiple feeding sites: a laboratory method intended for the determination of attractant/repellent properties of wood preservatives and baits
2001 - IRG/WP 01-20225
A method is introduced allowing the continuous monitoring of the activity of a small laboratory termite- colony at 8 different feeding sites simultaneously. The test assembly consists of a small central polycarbonate-tube containing a colonie of Reticulitermes santonensis (de Feytaud) beeing connected with 8 external feeding sites by small glass-capillaries. The termites passing through the glass capillaries to and from the feeding sites are interrupting an infrared light-barrier. Each signal from the light-barriers is conditioned and fed to a PC-based signal-recognition-, monitoring- and storage-system. First results show that a colony of 500 individuals of Reticulitermes santonensis (de Feytaud) will need approx. 2 to 3 weeks for establishing a new, full functional hierarchy. A well established Reticulitermes- colony will show 80 to 100 passings per minute to and from the eight feeding sites. The activity of Reticulitermes santonensis (de Feytaud) shows no circadian activity rhythmic.
M Pallaske, E Graf, H Takiuchi


Determination of total fluoride and boron in preservative-treated wood fluoride by ion selective electrode without steam distillation, and boron colorimetrically using azornethine-h
1998 - IRG/WP 98-20135
An analytical method was developed to determine total fluoride and boron in wood treated with aqueous or solid diffusing fluoride or borate-fluoride formulations. Ground wood was mixed with 30% sodium hydroxide solution and oven-dried for 2 hours before furnacing at 600° C for 1 hour. The cool fused product was dissolved in hot water, transferred to a plastic beaker and neutralised. Fluoride was measured by ion-selective electrode (ISE), after adding Ionic Strength Adjustment Buffers (ISAB), against appropriately pH and matrix-matched calibration standards containing 1, 3, 5, 10 and 50 ppm F. Boron was determined colorimetrically on the same neutralised solution using azomethine-H chemistry. Citric acid, sulphuric acid and nitric acid were evaluated as neutralising agents. While the choice of neutralising acid had no significant influence on the determination of boron by azomethine-H, speed and stability of the ISE for fluoride was best with nitric acid at 3.75M. The ISABs Sulphosalicylic acid and EDTA (SSA-EDTA); tri-sodium citrate and potassium nitrate; tiron and sodium nitrate; and TISAB were all evaluated for fluoride determination. Only SSA-EDTA was found to complex aluminium adequately, also accommodating borate, silicate and iron. Although SSA-EDTA has been traditionally used at pH 9.5 for the determination of fluoride in large amounts of aluminium, we found that use at this pH led to significant problems from hydroxide ion interference, slow electrode response, and pH changes due to loss of ammonia, all resulting in poor detection limits and reproducibility. To improve method performance, the pH of standards and samples was adjusted to 8.7, and all samples were spiked with an additional 1 mg/L fluoride. Interference from aluminium increased marginally, but the SSA-EDTA buffer was still capable of masking aluminium at a ratio of 20:1 AI:F, when measuring solutions containing 5 mg(F)/L. The method compared favourably with two alternatives; one employed the time-consuming distillation step included in the AWPA A2-1994 method, with a titration finish, and the second employed a double fusion and ISE finish, using TISAB buffer. Mean recovery from spiked Tasmanian oak (Eucalyptus regnans) at 0.05% - 0.20% m/m B/F was 95-105%. Precision at 0.2% m/m B/F in wood was about 3% for F and 1% for B. Detection limits of 30 mg/Kg for F and 20 mg/Kg for B were adequate for monitoring movement of toxicants within remedially-treated hardwood poles.
P A Collins, M J Kennedy


Determination of absorption, accumulation and transport of copper in mycelium of some wood decay fungi
1999 - IRG/WP 99-10323
Copper compounds are common wood preservatives. However, tolerance of some wood decay fungi to copper compounds has been observed recently. Therefore, we tried to elucidate possible causes of this phenomenon. We investigated uptake, accumulation and secretion of copper in the mycelium of potentially copper tolerant fungi (Antrodia sp.) and non tolerant fungus Trametes versicolor. We observed that potentially tolerant fungi have lower uptake of copper to the mycelium than non tolerant species. They also do not transport copper into the medium. That means that copper tolerance of fungi is probably based on low uptake of copper to the mycelium and not on the active transport from the mycelium to the medium.
F Pohleven, S Breznikar, P Kalan, M Petric


Evaluation of the pulsed-current resistance meter (Shigometer®) for determination of the internal condition of utility poles
1979 - IRG/WP 2128
A number of Telecom poles, which had been removed from service to be replaced by a radio link, were inspected using an electrical resistance meter (Shigometer®). These poles were creosoted, non-durable Victorian species in service in New South Wales. Six of these poles, chosen to represent various internal conditions typical of the range of the population tested, are discussed here. Data, from traditional assessment methods on the standing poles, from visual inspection, drilling and resistance testing after crosscutting, are presented together with photographs of a section of each pole. These data are presented to familiarise the reader with the obtaining and interpretation of electrical resistance values and to enable the reader to decide for himself whether this type of instrument may be a reliable and useful aid to the person determining the internal condition of service poles.
J D Thornton, W G Seaman, M McKiterick


Determination of the water sorption properties and preliminary results from field tests above ground of thermally modified material from industrial scale processes
2004 - IRG/WP 04-40279
In this study the differences in moisture behavior and durability above ground of heat treated wood originating from different European industrial heat treatment plants by means of the water sorption properties as well as field tests were examined. The manufacturers of heat treated material were: PLATO Hout B.V./Netherlands, Thermo Wood (Premium wood)/ Finland and Menz Holz/ Germany, where Oil-Heat treated Wood (OHT) is produced. Temporary evaluation of field tests showed a substantially improved resistance against biological attack of the thermally modified material compared to controls. The results of the laboratory tests regarding the determination of the Moisture induced Risk Index (MRI) showed a significantly reduced MRI of heat treated material compared to references. Material from the PLATO process and Oil-Heat treated material revealed significantly lower MRI values than Thermowood. Natural weathering above ground had so far no significant influence on the MRI of thermally modified specimens compared to the initial values.
C R Welzbacher; A O Rapp


Zur Analytik von Pentachlorphenol und Tetrachlorphenol in der Luft und im Urin. [On the analytics of pentachlorophenol and tetrachlorophenolin the air and in urine]
1979 - IRG/WP 3139
Because of its excellent fungicide and insecticide properties PCP has been used for more than three decades in the field of wood preservation. Recently, however, its application has been criticized repeatedly. The motives for criticism were diseases, the origin of which was supposed to be closely connected with the use of pentachlorphenolic wood preservatives. The quantitative evidence of this substance in the air and in biological material is, therefore, of decisive importance. This paper deals with the methods of determining analytically PCP and TCP in the air and in urine.
A Dahms, W Metzner


On-site test for indicative determination of leaching of components of preservatives from treated timber
1993 - IRG/WP 93-50001-12
In the late eighties the environmental concern about treated timber increased and it is still a hot issue in the Netherlands. From the environmental point of view three phases in the timbers life cycle can be distinguished: - the production phase - the service life - the waste phase. In the Netherlands at this moment much emphasis is laid on the production phase. In 1992 this has led to a new legislation in which several environmental aspects at the plants are settled. More about this Dutch Legislation is presented at this conference by Pasveer, Militz and Homan. One of the most important aspects of this new rules for the Dutsh timber treating companies is the determination of the leaching characteristics of their products by means of a so-called shower test (presented by Havermans, Boonstra and Homan at this conference). Both the Dutch timber treating industry and the controlling bodies in the Netherlands expressed their need for an indicative on-site test which does not have the diadvantages of the shower test. The Foundation for Timber Research SHR has been asked to develop this test in the second half of 1992.
W J Homan, H Militz


Gas chromatographic determination of 1,8-naphthalimide, N-Hydroxy-1,8-naphthalimide (N,N-naphthaloylhydroxylamine) and the sodium salt of N-Hydroxy-1,8-naphthalimide
2003 - IRG/WP 03-20259
A number of naphthalimide (NI) derivatives are used as efficient laser dyes, in medicine or in scanning electron microscopy. Only N,N-naphthaloylhydroxylamine (NHA) has been shown to be an effective wood preservative against wood decay fungi and termite damage. However, limited information is available concerning the analytical detection of NI-derivatives in treated timber. There is a clear need for the analytical characterisation; e.g. with regard to the penetration depth or the assessment of retention after leaching. This paper describes the development of a gas chromatographic method for determination of NI and their derivatives in timber. These investigations were carried out by means of direct thermal desorption-gas chromatography-mass spectrometry (TD-GS-MS) using the pure substances in solution, as well as direct analysis of treated southern yellow pine (SYP). It was shown that the identification of NHA in treated SYP is possible using this analytical technique. Furthermore first evidence is given for determining quantitative data. Surprisingly, the chromatograms and especially mass spectra obtained for NHA and the sodium salt of NHA are identical to the mass spectra of NI. The first results show that TD-GC-MS can be an option in determining the retention levels of NI and their derivatives in wood.
E Melcher, F Green III


Determination of ethanolamine in impregnated wood
2000 - IRG/WP 00-20198
Leaching of copper based preservatives from wood is usually prevented by adding chromium compounds to copper containing formulations. It seems that suitable substitutes for chromium fixation agents may be amines. In this paper, we report our results on interactions between copper(II) octanoate and ethanolamine (C2H7NO, 2-aminoethanole) with wood or its components. A part of ethanolamine from a wood preservative chemically reacts with wood and does not evaporate from it. This can be seen from retentions and from the changes of FTIR spectra of treated wood. We assume that ethanolamine mainly reacts with hemicelluloses and lignin complex. The unevaporated part of ethanolamine is even higher (for 2%) in the presence of copper(II) octanoate. We think that this difference originates from ethanolamine, which is complexed to copper(II) octanoate. Ethanolamine in wood can be easily determined with the indicator bromphenol blue in ethanol/acetic acid aqueous solution. Wood with ethanolamine turns blue while wood without ethanolamine remains yellow.
M Humar, M Petric


Determination procedure for wood preservatives in waste wood - statistics of sampling and analysis
1998 - IRG/WP 98-50121
In a RTD research programme funded by the German Federal Environmental Agency (UBA - Report No. 126-06-010103) a standardised and validated procedure was developed for sampling and analysing wood preservative components in waste wood. For this investigation a realistic quantity of waste wood from house demolition was used and 80 components analysed. The examination of single wood pieces and woodchips prepared therefore showed a good correlation with the retention of wood preservatives. For the estimation of the potential contamination of inhomogenic waste wood samples we developed a concentration-level model. There are three concentration-levels: Level 1: with preservative concentrations corresponding to waste of untreated - 'naturelike' - wood; level II: with concentrations higher than 'naturelike' wood and level Ill: with treated wood, under consideration of washout- and evaporation processes. For As, B, Cd, Cr, Cu, F, Hg, Pb, Sn, Zn, PAH (EPA), PCP, TCP and Lindane values were determined as known from naturelike waste wood. For calculating 90 percentile values a statistical method was used called "bootstrap" (n = 25). These values are interesting in context with the German waste law ("Kreislaufwirtschafts- und Abfallgesetz"), which prohibits the waste dilution and waste mixing. This demand causes specific problems in the production of chipboards when waste wood is used. The results indicate that the methods used for sampling and analysis can be applied for a safe and reproducible identification of wood preservatives in single wood pieces and shreddered wood chips.
P Stolz, J Krooss, U Thurmarm, R-D Peek, H Giese


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