Your search resulted in 39 documents. Displaying 25 entries per page.
European Biocides Directive (98/8/EC): Programme for systematic examination of all active substances of biocidal products on the market on May 13, 2000 Article 16(2)
2001 - IRG/WP 01-50166-03
K Rasmussen, A B Payá Pérez
Effects in vivo of various tensides (surface-active agents) on Reticulitermes santonensis De Feyteaud
2001 - IRG/WP 01-10417
The results of studies of surface active agents (tensides, surfactants) on the feeding behavior and mortality of Reticulitermes santonensis De Feyteaud are described. The effects of these agents on the nature and relative populations of eight gut-inhabiting symbionts are also examined. Among the various tensides tested, bee's poison was the most effective in causing rapid termite death. All surfactants were detrimental to the flagellated symbionts. The differences in magnitude and rapidity of the symbionticidal effects are described and discussed.
Inventory of the use of preservative-treated wood and wood preservatives in Sweden 1900-1997
1999 - IRG/WP 99-50137
The objective of this study was to present an overview of the use of wood preservatives and their active ingredients and industrially preservative-treated wood in Sweden since the beginning of the 20th century. The data presented in the report could for example be used as a basis for different waste management scenarios for preservative-treated wood. Before 1960 railway sleepers and utility poles were the most important preservative-treated commodities used in Sweden. Since 1960 sawn timber and other commodities have dominated the market. The total production of preservative- treated wood during the last ten years has been between 400 000 and 600 000 m3 per year. During this period about 60% of the production has been for the Swedish domestic market. A relatively small number of preservative types has been used in Sweden. Creosote has been used mainly for sleepers and poles. CCA dominates for sawn timber, but since 1994 preservatives based on other active ingredients than arsenic and chromium - such as ACQ, copper-azole and copper-HDO - have gained market for above ground commodities. Light organic solvent type preservatives (LOSP), with active ingredients such as organotin compounds and, recently, triazoles, were introduced in the 1970s for the treatment of external window joinery. Since 1900 up to 1997, in total, approximately 640 000 tonnes creosote, 14 000 tonnes arsenic and 9 000 tonnes of each of copper and chromium have been used in Sweden for industrial wood preservation for the domestic market only.
J Jermer, K Nilsson
Leaching of Active Components from Preservative Treated Timber. Stage 1: Semi-Field Testing
2004 - IRG/WP 04-20302
The project is aiming at finding realistic leaching rates from preservative-treated wood in use class 3 (above ground). The project focuses on developing a field trial method for investigating leaching. Panels are subjected to outdoor exposure under natural weather conditions at a test field at the Danish Technological Institute. The leachate is collected and monitored by chemical analysis of the active ingredients. The project is ongoing and the paper presents results from approximately 12 months’ of exposure. The study includes commercially available organic and inorganic fungicides using 4 different application methods: vacuum-pressure-, double-vacuum-, flow coat and supercritical treatment. Different test set-ups examine the influence of a number of different parameters. The results obtained from outdoor exposure will be compared with a laboratory test method (proposal of CEN/OECD, DOC TC38 WG 27 N039). The method investigated has proved to be useful in characterising the leaching behaviour from preservative-treated wood. The results from the present project are intended to serve as part of the basic documentation according to Directive 98/8/EC (The Biocidal Products Directive, BPD) for leaching of active ingredients in use class 3.
N Morsing, B Lindegaard
The biocides directive
1995 - IRG/WP 95-50040-25
The potential for accelerated ageing to determine the persistence of active ingredients in timber
2006 - IRG/WP 06-20323
Fast screening methods for evaluating the persistence of active ingredients in timber are proposed. This is an outline proposal which is intended to provoke discussion and further development of the methods. Reliable and accurate analytical methods are key to these tests.
L D A Saunders, M R Powell
Encapsulated Active Ingredients for Wood Preservation
2017 - IRG/WP 17-30717
Encapsulated organic fungicides and termiticides have been examined for use as wood preservatives in vacuum pressure treatment of wood. Encapsulation of active ingredients was found to improve wood penetration behaviour and reduces leaching as well as biodegradation of the active ingredients compared to industrial standard formulations.
E Oenem-Siakou, R Möller, R Craciun, J Wittenzellner, J Habicht
Migration of active ingredients from treated timber into fresh water
1991 - IRG/WP 3669
Spruce roundwoods and segments were treated with three different wood preservatives. Two of them containing copper and chromium the other one free of chromium. After fixation (3 weeks, 20°C) the specimens were leached by using artifical rain or by shaking the segments for one hour in contact with demineralized water. The water was analysed for the relevant elements of the preservative tested. Leachability of the components from the copper-chromate treated wood decreases. After 4-8 leaching cycles an almost constant migration of wood-preservatives, depending on the leaching method and the pH-value of water applied, was determined for the chromate containing preservatives. In the course of leaching cycles a constant rate of migrated copper from the preservative free of chromium was determined after 4 - about 17 leaching cycles. After 16 leachings of the segments the leached copper as calculated on the copper retention was determined to 1.6 - 5% for the chromium containing preservatives and about 22% for the tested variation of the new type of preservative.
H Klipp, H Willeitner, K Brandt, A Müller-Grimm
The potential of 2-deoxy-D-glucose as an active ingredient in wood preservation
1999 - IRG/WP 99-30205
2-deoxy-D-glucose (2-DOG) is a potential active ingredient against wood decaying fungi. When dissolved in water, it can be used in pressure treatment of wood. Thereby the wood is protected from attack by wood decaying fungi. A concentration of 1.5% (mean retention 9.7 kg/cubic meter sap-wood) is adequate for brown rot fungi, and 3% (mean retention 19.5 kg/cubic meter sapwood) will also provide protection against white rot fungi. 2-DOG is easily soluble in water, and is therefore easily leached from the wood upon completion of the preservation process. Different types of fixa-tion methods have been tried and evaluated. It is possible to produce 2-DOG by the hydrolysis of chitin, a constituent of the exterior skeleton of shellfish and insects. There is a potential for exploita-tion of this waste product provided by the crab and shrimp industry. The yield of 1 kg of fresh shrimp is 75 g of 2-DOG.
O V Frederiksen, A P Koch
Current models used by the European Health Authorities to evaluate the volatilization of active ingredients from treated wood used inside dwellings. A case study: Volatilization of azaconazole and propiconazole from treated wood
1990 - IRG/WP 3565
The use of wood preservatives inside houses may result in measurable aerial concentrations of active ingredients. These airborne contaminants may be inhaled by the inhabitants over periods lasting from a couple of days to several months. To assess the potential health hazard of preservative residues in the air, various risk-assessment models have been worked out. Three schemes, currently used by the European health authorities, are discussed in this paper. They are based on the saturated air vapour concentration, the volatilization rate measured in laboratory experiments and the aerial concentrations determined in practice. For each model various safety margins can be calculated. These are based on e.g. the subchronic inhalation toxicity, the acceptable daily intake and the acceptable aerial concentration of the insecticides and fungicides used in wood preservatives. In order to demonstrate the feasibility of these health- assessments, a case study has been carried out with the fungicides azaconazole and propiconazole, developed by Janssen Pharmaceutica - Belgium.
A R Valcke, L Van Leemput
An in-ground natural durability field test of Australian timbers and exotic reference species. Part 5: Extensive data from a site where both decay and termites are active. Results from a full-replicated set of heartwood specimens from each of ten myrtaceous hardwoods after 18, 19 and 20 years' exposure - A discussion paper
1988 - IRG/WP 2324
Extensive data are presented on the decay situation, the termite situation and the decay-termite associations; all gathered from a fully-replicated set of heartwood specimens of 10 hardwood timbers after 18, 19 and 20 years' exposure in the ground at a single test site, i.e. a semi-arid steppe site. Sixteen tables are presented in addition to the one table providing the rating data; the latter representation of specimen condition being essentially all the data normally being recorded from field tests, whether these be of natural durability or preservative treated specimens. The authors give this "extra" data to show the type of information obtainable as a result of applying both mycological and entomological expertise to field assessments. Instead of discussing these results. the authors wish to generate some discussion by asking questions such as - is some of all of this information of value? - What additional/alternative information would interested scientists wish to see with respect to the most durable timbers in a test such as that examined in this report?
J D Thornton, G C Johnson, J W Creffield
Developements in the EEC on the regulation of wood preservatives
1993 - IRG/WP 93-50016
There is a wide variation in the regulation of wood preservatives within the EEC, ranging from product by product authorization under persticides legislation to controls via standards, or simple compliance with basic requirements on classification packaging and labelling. During the past two years the commission of the European Communitiesn has worked on a proposal concerning the placing on the marketof biocidal procducts. This includes wood preservatives. The proposal is aimed at ensuring completion of the internal market in respect of these products and providing a high degree of protection for man and the environment. It provides for the creation at the Community level of a positiv list of active substances with authorization of individual products by member states. Provision is made for mutual authorization of products containing active substances of the positive list. Applications for authorization must be supported by data. Common principles for evaluation of applications will be developed and a programme for review of eyisting active substances will be established.
Remedial treatments of glulam = diffusion of active ingredients through glue lines from solid wood diffusable preservatives
1996 - IRG/WP 96-30117
Diffusable preservatives are very suitable for use in remedial treatments of laminated beams in which too high moisture content involves the development of wood destroying fungi. The diffusion of active ingredients (boric acid, disodium octoborate, bifluoride) is well observed in solid wood but in a composite wood, the glue lines may appear not only as a barrier for the diffusion but also, may be mechanically affected by the diffused active ingredients. Shear tests were carried out on glulam specimens manufactured with different types of glues: resorcine (RF), ureaformaldehyde (UF), polyurethane (PUR) and polyvinylacetate (PVAc). Diffusion tests were also carried out in accelerated wetted glulam specimens with three diffusable solid preservatives differently exposed in the test samples. Results observed with boron compounds showed that their diffusion does not affect the mechanical resistance of the beams. In another hand, interesting results were obtained concerning the passage of boron and bifluoride through some types of glues. These results will contribute to the optimization of the remedial treatment of glulams.
D Dirol, S Mouras
Isolation of soil borne bacteria and fungi from treated timber
2001 - IRG/WP 01-50174
Most research in the last few decades has focused on the development of new strategies to control biological attack and the means to quantify this. Comparatively little work has been done to examine the effect that treated timber might have on its surrounding environment. This presentation will describe a methodology that attempts to detect any changes which might occur in the soil microflora following the introduction of timber treated with a number of chemical agents containing organic active ingredients (a.i.). It was also the purpose to isolate organisms that can break down organic a.i.. A technique was developed to determine whether the presence and nature of a timber preservative influenced the size and composition of a microbial population that colonised timber when buried in soil. Samples of treated timber were incubated in a solution eluted from soil that contained a diverse, viable microbial population. After incubation, the size and composition of the microflora both in the eluate and adhering to the timber was examined.
I Stephan, A Stegemann, G Heidrich
Leaching of active components from preservative-treated timber - Ongoing research: Status after approx. 4 months’ out-door exposure
2003 - IRG/WP 03-20276
The Danish Technological Institute is together with manufacturers of active ingredients and formulators of wood preservatives running a project aiming at finding realistic leaching rates from preservative treated wood in hazard class 3 (above ground). The project is focussed on developing a field trial method for investigating leaching. According to BPD hazard assessment has to be carried out for biocide products and a part of that includes possible environmental impact of preservative treated wood. Leaching of active ingredients from treated wood has to be measured and assessed. Several organisations (CEN, OECD and others) are in progress of developing laboratory leaching test methods. In order to give more realistic data for leaching of active ingredients it is important to study natural exposure. According to recent publications (IRG/WP 01-50171), it appears to be a significant difference between natural leaching and laboratory leaching methods and a relative comparison is, therefore, needed. Data from close to practice applications are important in order to support products in the BPD. Furthermore, the results are needed to provide benchmarking data to allow other laboratory or accelerated leaching data to be put into perspective. The results from the project are intended to serve as part of the basic documentation for leaching of active ingredients in hazard class 3. Panels are exposed outdoors under natural conditions at the field trial at Danish Technological Institute and the leachate is collected and monitored by chemical analysis of the active ingredients. The project is ongoing and the paper presents results from approximately 6 months of exposure. The study includes commercially available organic and in-organic fungicides using 4 different application methods: pressure-, vacuum-, flow-coat- and supercritical treated wood. Different test set-ups are investigated and the results obtained from outdoor exposure will be compared with a laboratory test method (CEN/OECD). Furthermore, the laboratory method suggested by CEN/OECD is evaluated and suggestions for improvement are stated.
The EWPMG proposal for the environmental risk assessment of wood preservatives
2001 - IRG/WP 01-50166-09
This paper reviews the protocol prepared by the European Wood Preservative Manufacturer's Group, which could be used by an applicant for product approval under the Biocidal Products Directive 98/8/EC, to produce a risk assessment for an active substance or product in the Product Type 8 Wood Preservatives, in support of the application. The background and scope of the protocol are reviewed. The principles of environmental risk assessment are reviewed with particular reference to wood preservatives. The protocol is described and an example flowchart is included.
E F Baines
Lignin degradation by a non-enzymatic system supposed to be active in white rot fungi
2000 - IRG/WP 00-10340
Electron microscopic investigations have shown that ligninolytic enzymes of white-rot fungi are only able to penetrate the wood cell wall in late stages of degradation. Thus, the selective degradation of lignin of certain white-rot fungi can only be explained on the basis of a low molecular weight, highly diffusible system. A system, consisting of copper, a coordination compound and either H2O2 or organic peroxide was found to be highly ligninolytic and has been proven on different types of lignin model compounds. In this paper, it is shown that this system is also capable of delignifying soft and hardwood lignin. Delignification was indicated on wood sections by differential staining with astra-blue and safranine and was quantified by UV-microscopy in cell walls. It was demonstrated that especially when organic peroxide was used in the copper system, even the recalcitrant softwood lignin was depolymerized while with H2O2 only hardwood lignin was oxidized efficiently. Due to the selectivity of lignin degradation it is assumed that rather peroxyl, alkoxyl or carbon centered radicals than hydroxyl radicals are the active compounds. In principle the copper system is comparable to the diffusible system active in brown-rot, but with the latter one leading to cellulose degradation. A deeper insight into the mechanism of white-rot decay, including also the likelihood of non-enzymatic reactions could alter the generally accepted picture of purely enzymatic reactions and could probably offer a new approach to chemical wood preservation.
P Lamaipis, W Gindl, T Watanabe, K Messner
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 4: Analysis of extracts and treated wood for active components
2000 - IRG/WP 00-20215
In order to facilitate the commercial implementation of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, it has been essential to develop analytical methodology for the important bioactive components of the heartwood extract. This methodology will be used 1) to standardise the activity of successive production batches, ensuring that batch-to-batch variation is controlled, and 2) to monitor the penetration and retention of active components in extract-treated wood, ensuring that treatment quality is controlled. Analytical techniques used through the project have included both LC/MS and GC/MS, but as most of the extract activity against termites and fungi has now been demonstrated to reside in the lighter fractions, we have concentrated on GC/MS for the routine methodology for both extract activity and wood retention. Penetration is monitored by the application of a chromazurol S spot-test to a freshly cut transverse section. Both cypress heartwood and penetrated sapwood turn red-purple under the conditions of the test, which is not necessarily specific for cypress extractives, but nevertheless useful for routine monitoring of penetration of cypress extracts.
Hui Jiang, M J Kennedy, L M Stephens
The remaining concentration of inorganic wood preservative components in EN 252 stakes after ground contact
2000 - IRG/WP 00-50159
In order to determine the biological efficiency and the remaining concentration of different inorganic and organic active ingredients during service, EN 252 specimens were impregnated with 3 copper based wood preservatives. The stakes were installed in the test field of the DESOWAG GmbH, Rheinberg, for at least 7 years. At the end of the field test some of these stakes were divided into 10 uniform segments. Afterwards each segment was milled and mixed to guarantee a nearly homogenous sample. After further sample preparation like an acidic digestion the remaining concentration of the inorganic components copper, zinc, boron and fluoride were measured by means of AAS, ICP and an ion selective electrode. Concerning the remaining concentration the following ranking of the investigated active ingredients could be deduced: Cr (90%)> Zn (60%)> Cu (40-70%) >= F (40%) > B (concentration <10%). Furthermore the results show that the remaining content of copper differs depending on the wood preservative used. The lowest content was detected for the CCZnF-formulation, the highest for the copper-quat-preservative. Furthermore it is obvious that the rate of biological decay correspond well with the distribution of the wood preservative components in the segments.
E Melcher, H-W Wegen
Persistance of active ingredients in treated wood
1993 - IRG/WP 93-50001-20
Disposing of chemically protected waste wood implies the distinction between surface and pressure treatment. Considering that barked round-wood merely contains, after 7 months open storage, less than 30 g per ton of bark or 25 mg per ton of sapwood, depending on the type of insecticide, the bark or sapwood shavings may be incinerated normally, according to less severe legal prescriptions than for pressure treated wood. Past use poles, destroyed by fungi, will indeed have to be disposed of in specially equipped incineration plants, which respond to strict requirements regarding the waste air.
E Graf, P Manser, S Rezzonico, B Zgraggen
Leaching of active components from preservative-treated timber. Stages 2 & 3: Laboratory testing and comparison with semi-field testing
2004 - IRG/WP 04-20303
This part of the project is focussed on leaching from preservative-treated wood obtained by the laboratory test method CEN/OECD draft guideline, February 2003 ”OECD guideline for the testing of chemicals proposal for new guideline XXX. Estimation of Emissions from Preservative-treated Wood to the Environment: Laboratory Method for wood held in the storage yard after treatment and for wooden commodities exposed in Use Class 3 (not covered, not in contact with the ground).” Preservative-treated test specimens are emerged in water. The specimens are immersed two days a week in a 60 days period. On each immersion day 3 immersions are carried out. One sample is immersed in water 18 x 3 times. Each immersion takes one minute. Between each immersion the specimens are stored in climate chambers. Water (emissate) is retained for chemical analysis for active ingredient to determine the leaching. The study includes commercially available organic fungicides using vacuum-pressure treatment as an application method. The preservative used is the preservative used in Nordtest project 1582-02 named M1. The investigation includes two different periods of fixation, one with a long fixation period and one with a short fixation period of the active ingredient before the immersion testing. The results obtained from laboratory testing are compared with the semi-field exposure. The method developed for in-service testing has proved to characterise the leaching behaviour from preservative-treated wood. However, there is no good correlation between field-testing and the CEN/OECD laboratory testing method for the product involved.
N Morsing, B Lindegaard
Estimation of the impregnation degree of pine wood by the distribution analysis of active ions concentration in the cross-section
1999 - IRG/WP 99-20174
Samples in the form of pine wood rollers of diversified moisture content of ca. 50, 28 and 12% were impregnated with a water solution of the mixture type CCB with the use of the full-cell process. Moisture content was determined in individual layers from the girth to the pith. In the same way the concentrations of copper and chromium ions with the use of the spectrophotometric method and recalculated to the total dry mass of the preservative. Simultaneously, there was performed biological test according to EN 113 for the investigated mixture and different concentrations: 0,1; 0,16; 0,25; 0,4; 0,63; 1,0; 1,6; 2,5. The obtained fungicidal value let to determine the depth of biological resistance of impregnated wood within the impregnated zone.
K Lutomski, B Mazela
The ecotoxicology assessment of wood preservatives and their active ingredients by means of germination tests using cress - A critical consideration
1999 - IRG/WP 99-50125
With putting the Biocidal Products Directive 98/08/EC (BPD) in place an environmental risk assessment for wood preservatives and impregnated timber is requested. To assess possible risks, suitable test methods are required, which reveal the ecotoxicological profile including environmental fate and behaviour of treated commodities. Germination and growth tests could contribute to the determination of ecotoxicological effects on plant seeds and their embryos. Investigations were carried out in order to determine the germination and the growth behaviour of cress with the aim, to investigate the possibilities and limitations of these tests. The results show that the cress germination test is very sensitive as a rule. A prevention of the germination as such does not indicate a possible toxicity of the formulation investigated. The assessment of the germination processes as the only criterion is not a sufficient measure for the ecotoxicological profile of wood preservatives and impregnated timber. Germination tests, however, can supply a first indication concerning a possible effect on the environment. In connection with the other methods, it is possible to receive supplementary information in a very short time.
P Jüngel, A O Rapp, E Melcher
Animal blood protein as a component of new, non-toxic wood preservatives fixing organic active compounds in wood
2003 - IRG/WP 03-30312
Application of natural organic compounds and simple physico-chemical treatments in wood conservation has, as its objective, not only its protection against biological agents but, equally importantly, protection of natural environment by gradual abandonment of toxic constituents still applied commonly on a wide scale. The introduction into wood of new, non-toxic impregnation agents manufactured on the basis of animal proteins aims to create an effective protection against biological factors, primarily the reduction of the degree of leaching out of the impregnation agent from wood. Experiments were carried out on the effectiveness of mixtures of carboxyl acids with animal blood protein against Coniophora puteana fungus. The object of the performed investigations was sapwood of Scots pine (Pinus sylvestris L.) impregnated with mixtures of carboxyl acids and animal blood plasma. Directly after impregnation, wood was subjected to thermal treatment with the aim to denaturate proteins. Mycological investigations were carried out using an accelerated agar-block method according to procedures described in EN 113 and EN 84 standards. The objective of the performed studies was to assess the effectiveness of blood protein as a constituent reducing the process of washing out of preservatives from wood. A low weight loss of samples saturated with the formulation containing propionic and ethyl buthyl acids and animal protein applied in the form of SOLUTEINTM preparation was demonstrated. The degree of leaching of carboxyl acids as active constituents from wood saturated with tested mixtures was estimated applying a mycological test as well as on the basis of chemical analysis of aqueous extracts from the leaching process. The performed experiments showed good protection properties of protein, which reduced effectively the extent of leaching of the active substance from wood.
B Mazela, I Polus
Method to determine the depth of penetration of the biologically active components of wood preservatives
1978 - IRG/WP 2108
A time-saving method for determining the depth of penetration of the biologically active components of wood preservatives is described. The test specimens were obtained by cutting thin slices from the wood either parallel or perpendicular to the treated surface. The slices were then exposed to fungal attack. A good correlation was found between the test results obtained by the modified German Standard method (plane-off test), published by BECKER and STARFINGER (1971).