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Life cycle analysis of utility poles. A Swiss case study
1995 - IRG/WP 95-50040-05
Use of preservative-treated wood products faces increasing public and political pressure because of environmental concerns regarding the chemicals used to protect the wood. However, critics usually focus only on one single aspect of the whole life cycle of treated wood products, disregarding other environmental effects of timber utilization. To evaluate the ecological consequences of wooden utility poles (CCF/CCB impregnated roundwood and glulams) and their alternatives of reinforced concrete and steel, a life cycle assessment was conducted. Based on data from existing Swiss electricity transmission lines, a comprehensive inventory was established of all extractions from, and emissions to the environment caused by each process step. This inventory data was linked to possible environmental impacts using various aggregation methods. An evaluation was made for single poles as well as for whole transmission lines. The results show that impregnated roundwood utility poles in fact have certain environmental benefits when considered over their whole life cycle.
T Künniger, K Richter
The use of a physical field model to study the effects of remedially treated timber on the growth of perennial ryegrass (Lolium perenne) and rye (Secale cereale), and the accumulation of toxic preservative constituents in Lolium perenne
1995 - IRG/WP 95-50040-02
Low cost laboratory model systems can be used to give relatively rapid indications of the environmental effects of preservative treated timber in soil contact. This paper details the effects of remedially treated timber on the growth of crops of Lolium perenne and Secale cereale seeded on soilbeds of different texture in close proximity to remedially treated creosoted pole sections. Lolium perenne sward samples were subjected to chemical analysis for fluoride and chromium content to identify bio-accumulation of these toxic preservative components. Significant but variable reductions in the dry weight yields of Lolium perenne samples were found in conjunction with increased fluoride and chromium contents, together with significant reductions in the density of Lolium perenne swards. The difference in soil texture however was found to be a more significant influence on the growth of Secale cereale than the presence of treated timber. Secale cereale plants within a crop canopy established on the lighter textured soil were characteristically larger and more numerous than plants from canopies on heavier soils. Results are discussed as part of an overall environmental assessment of the remedial treatment and in terms of the suitability of the physical field model as a testbed for such plant studies.
D C R Sinclair, G M Smith, A Bruce, H J Staines
Preliminary studies to assess the effects of aeration and lowered humidity on the decay capacity, growth and survival of the dry rot fungus Serpula lacrymans (Wulf ex. Fr.)
1997 - IRG/WP 97-10208
Novel microcosms were used to test separately the effects of aeration and humidity on the decay capacity, linear spread and survival of Serpula lacrymans. The application of a pumped air supply resulted in an effective cessation of fungal activity when all but the lowest of the air flow rates was used. Furthermore, the lowest air flow rate caused marked growth tropisms away from the stress. In separate chambers used to create a range of relative humidities, growth and decay were permitted only in the higher humidity regimes. In both the air flow and the humidity experiments, the loss of growth and decay abilities was not always accompanied by a loss of fungal survival. A test to compare the decay capacities of domestic building isolates and "wild" Himalayan isolates of S. lacrymans was also performed, as were comparisons of radial growth rates on malt agar. Significant differences between the two groups occurred in both tests.
G A Low, J W Palfreyman, N A White, H J Staines, A Bruce
Effects of CCA treatment on settlement and growth of barnacles under field conditions
1998 - IRG/WP 98-50116
As part of a field experiment at seven European marine sites evaluating the effects of CCA treatments on non-target marine organisms, panels treated to nominal loadings of 12, 24 and 48 kg/m3 CCA were exposed at marine sites around the coast of Europe. Within two weeks of exposure, a heavy settlement of barnacles took place on the panels exposed intertidally in France. The intensity of settlement was measured after four weeks. It was found to vary significantly with preservative loading and this variation could be described by a positive linear regression - the higher the loading, the higher the numbers of barnacles settling. The survival and growth of barnacles was assessed after six months exposure. Observations of numbers of identified adults on test panels from other sites suggested that some species of barnacle settle preferentially on CCA-treated wood while others do not. The findings give an insight into the impact during the period of greatest potential for leaching of heavy treatments with CCA on organisms living in intimate contact with the treated surface.
S M Cragg, C Brown, R M Albuquerque, R A Eaton, P Goulletquer
Evaluation of ecotoxicological effects of different coniferous wood treatments on two marine bioindicator species
2022 - IRG/WP 22-10999
Coniferous wood panels (Picea abies) were treated with two concentrations of copper-based impregnating agent to increase its durability in marine and brackish environment. In order to assess the environmental compatibility of the treatments a laboratory experiment was conducted with two marine invertebrate species: bivalve Mytilus galloprovincialis and a gastropod Steromphala albida. The bioindicator organisms were maintained for 4 weeks in experimental tanks under semi-static condition at control (without wood panels), NTC (non-treated wood panels), CuI (wood panels treated with 0.033% Cu solution) and CuII (wood panels treated with 1% Cu solution) conditions. After 2, 8, 18 and 25 days, water samples were collected to analyze copper release over time. The presence of oxidative stress was evaluated through the determination of catalase and glutathione-s-transferase enzymes activity, the response to metal exposure through metallothionein levels and the presence of neurotoxic effects through acetylcholinesterase activity determination. For the evaluation of possible genotoxic effects in mussels, presence of micronucleus in hemocytes was evaluated, while physiological responses in mussels and behavioral endpoint in snails were evaluated with survival in air test and flipping test, respectively. CuII condition exhibited the highest toxicity and in both mussels and snails, mortality was significantly affected reaching 100% before the end of the experiment. Conversely, results of all biomarker analyses allowed to exclude toxic effects of NTC and CuI conditions on the two model species. Toxic effect observed in CuII are consistent with copper concentration that was above 200 and 400 ppb after 2 and 8 days of exposure respectively, while was below 50 ppb during all the experiment in the other tested conditions.
T Marčeta, N Nesto, I Guarneri, D Tagliapietra, V Moschino
Danish wood preservatives approval system with special focus on assessment of the environmental risks associated with industrial wood preservatives
2001 - IRG/WP 01-50166-01
The following is a description of the procedure used by the Danish Environmental Protection Agency to assess the environmental risks associated with preservatives used in the pressure impregnation of wood. The risk assessment covers issues considered to be of significance for the environment and which are adequately documented so as to allow an assessment. Such issues are persistence and mobility in soils, bioaccumulation and the impact on aquatic and terrestrial organisms. Unless required in special circumstances, the assessment does not apply to birds and mammals as the normal use of preservative treated wood is not expected to involve any noteworthy exposure of these groups. Approval of wood preservatives will be based on a general assessment of the environmental risk associated with the normal use of wood treated with the preservative in a realistic worst case situation. The assessment may address other aspects such as disposal and total life cycle.
Improvements of monitoring the effects of soil organisms on wood in fungal cellar tests
1996 - IRG/WP 96-20093
Accelerated testing the durability of preservative treated timber in a so called "fungal cellar" or "soil-bed" to evaluate its performance in ground contact is widespread practice. In order to obtain a more accurate and reproducible estimate of preservative performance, several institutes, among them the BAM in Berlin, have routinely carried out static bending tests in addition to visual examination. These tests were usually performed with a defined maximum load or deflection path regardless of the remaining degree of elasticity of the test specimens. Recent studies at the BAM revealed that by modifying the method, i.e. by restricting the applied load to the non-destructive interval for each individual test specimen, the calculated modulus of elasticity (MOE) reflect the changing strength properties caused by biological deterioration and allow within a relatively short time valuable predictions on the service life of the treated timber in soil contact.
I Stephan, S Göller, D Rudolph
The applicability of life cyle analysis and alternative methods in the wood preservation industry
1994 - IRG/WP 94-50023
In the Netherlands, several case studies have been performed using the life cycle analysis method (LCA). This type of research is aimed at an inventory and classification (sometimes including also evaluation) of the environmental impacts of a product, from the raw material to waste stage ("cradle to grave" approach). In a LCA each environmental impact is assessed in terms of, for example, mass of raw material use (kg), energy consumption (MJ), emissions (COx, NOX, SOx, etc.) and final waste (in kg). The critical point in an LCA is the definition of comparable "functional units" for similar products made of different materials with different service lifes. As the LCA method has often proved to be very complex, lime-consuming, expensive and difficult to interpret and translate into practically usefull results, alternative methods are developed. Three methods are described and compared on the basis of various examples. It is hoped that this may be of use as a starting point for further discussion on the suitability of applying the LCA on (preservative treated) timber products.
P Esser, J Cramer
Environmental status of wood preservation in the UK
1994 - IRG/WP 94-50018
The environmental status of wood preservatives and treated wood in the UK is summarised. The current legislatory position with respect to approvals, supply, use and waste disposal is considered. The bibliography at the end of this paper contains details of all publications referred to together with other relevant information although this cannot be exhaustive.
Programme section 5, Environmental aspects
1997 - IRG/WP 97-50099
Programme section 5, Environmental aspects
1996 - IRG/WP 96-50077
An investigation of the effects of pre-steaming on the treatment of sawn spruce timber with Celcure A, a copper-chrome-arsenic preservative
1981 - IRG/WP 3150
Difficulties in the treatment of spruce using standard vacuum/pressure techniques with both water-borne and organic solvent preservatives are well known. We have evaluated the influence of steaming on treatability with a waterborne CCA preservative.
C R Coggins
The registration of wood preservatives under the Pesticides Act of 1962 in the Netherlands
1976 - IRG/WP 364
J Van der Kolk
Antagonistic effects of a range of fungi to Serpula lacrymans
1996 - IRG/WP 96-10156
Certain fungi have been demonstrated to exhibit antagonism towards Serpula lacrymans in culture. Species from the genera Trichoderma, Gliocladium, Penicillium and Hypomyces were among those exhibiting the strongest antagonism. Certain species showed antagonism in a range of media of varying nutritional status. The possible role of antagonistic fungi as biocontrol agents for Serpula lacrymans is discussed.
P Rattray, G McGill, D D Clarke
Programme Section 5 Environmental aspects
1999 - IRG/WP 99-50138
Loss of preservatives from treated wood during service
1992 - IRG/WP 92-3734
During the 23rd IRG conference in Harrogate the matter of preservative losses from treated wood during service was raised. We were asked to collect information in this field and ask now for help from you. Many tests have been carried out at a laboratory scale to study fixation and leaching from wood treated with different preservatives. Very little, however, is reported on losses of preservatives during service. Since these values are of great relevance regarding environmental impact and the final disposal, reuse or recycling of treated wood, it is of great importance to get as much information as possible on the amount of active ingredients lost during service life. We are convinced there are quite a lot of analytical data and additional information available in many places all over the world. It appears to be rewarding to collect those data and put them together adequately to get an astimate of the losses of the different components based on a broad scale of in service situations. This work will be done as soon as information is available and it is intended to present the results on next IRG meeting.
M-L Edlund, D Rudolph
A discussion on causes, effects and remedies of arsenic pollution of groundwater in Bangladesh
1998 - IRG/WP 98-50102
This paper includes possible causes, effects and remedies of arsenic pollution of groundwater in Bangladesh, extracted mostly from the international conference held in Dhaka in 1998. Next possible key steps have been suggested based on scientific principles and experience. The release of arsenic from underground sediment would be due to excessive mechanical forces, geochemical and geobiological reactions. Arsenic free water will cure acute patients and will save future generations. Use of suitable organic chemicals, organic matters, biological control system would be widely acceptable for supplying arsenic free water. Other natural sources of water can be used easily and safely without mechanical and chemical processes. The problems of chronic patients would be solved genetically, enzymatically and nutritionally.
A K Lahiry
Effects of acetylation on the dimensional stability and decay resistance of kenaf (Hibiscus cannabinus L.) fiberboard
1996 - IRG/WP 96-40059
The objective of this study was to investigate the influence of the acetylation treated kenaf fiber, Phenol formaldehyde resin content level, and three fungi species on the dimensional stability and decay resistance of high density non wood composition boards. A standard ASTM method was used to evaluate weight loss and thickness change. The linear shrinkage and expansion of each species were also determined. All specimens were exposed to decay chambers for 16 weeks. Test results indicated that most of the main factors significantly influence the thickness, length changes, and decay resistance of the high density kenaf fiberboards.
P Chow, T Harp, R Meimban, J A Youngquist, R M Rowell
Leaching of components from water-borne paints and fungitoxic effects
1995 - IRG/WP 95-20062
Water-borne model paints, acrylics and alkyd emulsion paints, of known composition were leached according to a procedure modified in accordance with ASTM 6271.1. The effectiveness of fungicidal compounds in the painted specimens before and after leaching was evaluated with a biotest in which Penicillium brevicompactum was used as a test fungus. The leaching of the fungicide Troysan Polyphase according to the biotest varied to a high extent depending on differences in paint composition. Fungicide efficiency in relation to paint formulation and fungicide mobility in a paint film is briefly discussed.
The evaluation of synergistic effects of chemicals on fungicidal efficacy in crossed-paper tests
1991 - IRG/WP 2383
The mixing effects of wood preservatives were evaluated using the crossed-paper technique. Two filter paper strips (0.7 x 8 cm²) were treated by soaking with different chemicals [fungicides, a termiticide (chlorpyrifos or phoxim), a surface-active agent, a synergistic agent, and a stabilizer], and placed at right angles to each other on a fully grown mycelial mat of a test fungus in a Petri dish. When the four organoiodine fungicides were incorporated with chlorpyrifos or surface active agent, only 3-iodo-2-propynyl butyl carbamate (IPBC) showed the desirable synergistic effect against every wood-decaying fungus tested. Other fungicides did not always tend to produce the synergistic effect with the addition of a surface active agent. 4-Chlorophenyl-3-iodopropargyl formal (IF-1000) appeared to indicate an undesirable antagonistic effect when mixed with either chlorpyrifos or a surface active agent. 3-Bromo-2, 3 diiodo-2-propenylethyl carbamate (EBIP) did not show any synergistic action by mixing with chlorpyrifos and/or a surface active agent, although the fungicidal enhancement was induced satisfactorily by mixing the fungicide with chlorpyrifos, a stabilizer and/or a synergistic agent, especially against Tyromyces palustris and Coriolus versicolor. Similarity of the results obtained in the present investigation and in the previous laboratory decay tests leads to the conclusion that the crossed-paper technique is suitable for the evaluation of the mixing effect of chemicals on fungicidal efficacy.
Dong-heub Lee, K Tsunoda, M Takahashi
Effectiveness and synergistic effects between copper and polymer betaine
1996 - IRG/WP 96-30097
Different formulations of "Copper Amine" and Polymer Betaine were studied. During laboratory tests a synergism between both active ingredients against soft rot and dry rot has been found. The efficacy against soft rot according to the "BAM method" and the European Standard ENV 807 depends only on the amount of copper. Long term tests in a fungus cellar for determining the relative protective effectiveness in ground contact show similar results as CCA-treated wood.
H Härtner, V Barth
Effects of various preservative treatments on the mechanical and physical properties of plywood
1993 - IRG/WP 93-40007
The technical properties of plywood are related to both the intrinsic characteristics of its composing wood species and the quality and performance of the glue bond which acts as an interface between veneer sheets. Consequently mechanical and physical testing and glue bond strength analysis offer an appropriate means for studying the effect of preservative treatments on the overall quality of plywood. A range of boards was treated with waterborne and oilborne preservatives. Changes in modulus of elasticity, modulus of rupture and tensile strength were noted as well as variations in physical properties. Analysis of the glue bond strength was done by shear strength testing and determination of the amount of wood failure after different ageing procedures.
J Van Acker, M Stevens
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.
Effects of a chitin synthesis inhibitor on spore germination of the decay fungi Gloeophyllum trabeum and Poria tenuis
1986 - IRG/WP 2253
This study sought to determine the effect of a chitin synthesis inhibitor - Polyoxin D, on spore germination and early hyphal development of a brown rot and a white rot fungus in-vitro. Polyoxin D is a competitive, substrate-analogue type of chitin synthtase inhibitor (2). The drawbacks to use of such a compound as a wood preservative tie. cost - $20,000/g, possible leaching or degradation) might be reduced should it be effective in preventing decay initiation by spore germination at very low concentrations.
E L Schmidt
Rates of emission from CCA-treated wood in the marine environment: measurement, modelling and requirements for further research
2001 - IRG/WP 01-50166-12
Accurate estimates of rates of emission of leachate from preservative treated wood are crucial for realistic predictions of the environmental impact of its use in maritime construction. Estimates are available for some commonly used preservatives, but these vary widely. Though variable, these measurements suggest that emission generally decreases exponentially with time. Part of the variation is due to differences in methodology employed. Physical and chemical characteristics of the seawater used (e.g. temperature, salinity, pH and oxygen content) affect emission rate. So too do the specifics of the treatment process especially the preservative formulation used, and pre- and post-treatment handling of the wood. The nature of the treated wood samples is also important, with misleadingly high estimates being obtained from samples with unrepresentatively high proportions of cross-cut surfaces. A suggested strategy for developing an informative and standardised methodology is discussed. To form useful models of impacts of leaching, emission rates need to be considered in conjunction with site-specific information regarding a) water exchange rates between the area where leaching occurs and the sea, and b) the extent of partitioning of leachate between the water column, biota and sediment. The risk of environmental impact may be reduced by modification to treatment procedures and by careful planning of installation.
S M Cragg, C J Brown, R A Albuquerque, R A Eaton