Your search resulted in 82 documents. Displaying 25 entries per page.
Tributyltin compounds in wood preservation: Health and safety aspects
1986 - IRG/WP 3396
The toxicity of organotin compounds of the general formula RnSnX(4-n) depends strongly on the type of organic substituent R and on the degree of substitution n. The residues X, not bound through a tin-carbon bond, are however of much smaller influence. Furthermore, there is evidence that hydrolysis of tributyltin esters will occur under environmental as well as under physiological conditions to TBTO or its corresponding derivatives. Thus TBTO can be considered a model substance in the risk evaluation for tributyltin compounds TBTX. Along with industrial hygiene considerations of TBTO and tributyltin esters, the strong local irritation and high toxicity in aerosol form when testing undiluted material must be noted. However, the tolerance of model wood preservatives containing 1% w/w TBTO, 2% W/W TBTN and 2% w/w TBTL on the skin of human volunteers after single exposure was not different from that of the vehicle alone. Vapours of TBTO, tributyltin naphthenate and benzoate proved to be practically non-toxic in single exposure studies with rats. After repeated administration of TBTO to rats in the feed (4 and 13 weeks) and in aerosol form (4-5 weeks) toxicity to lymphatic organs predominated. After aerosol exposure additionally severe irritation of the respiratory tract occurred. No adverse reactions were observed in rats exposed for 4-5 weeks to vapour practically saturated with TBTO. With both application routes (oral and inhalation) no indications were found of damage to the nervous system, as is the case for lower homologues of the trialkyltin series. Our results of testing for genotoxic potential in micro-organisms, human lymphocytes and in the micronucleus test in mice do not indicate a mutagenic or carcinogenic potential. Further mutagenicity data from a WHO/IARC multi-centre study are in part contradictory. They do, however, not indicate a definite mutagenic hazard. Moreover in teratogenicity studies in mice and rats TBTO did not show embryotoxic including teratogenic properties at dose levels that were not toxic to the dams. From the no-effect level in the 4-5 week inhalation study a 24 hour exposure limit value for humans can be derived. This acceptable room air concentration can be compared with results of a model study, in which the concentration over wood blocks treated with preservants containing 1.5 and 3.0% tributyltin naphthenate was measured. Based on this evaluation there are no objections to a large surface application of wood preservatives of the tested composition in room interiors. Nevertheless the general rule should be observed, that formulations containing biocides should be used only where there is a definite necessity for them.
H Schweinfurth, P Günzel, H A B Landsiedel, R Lang, R Reimann, C Schöbel, F Siegmund
A suggested method to test the toxicity of wood preservatives towards the house longhorn beetle
1977 - IRG/WP 275
This method was developed in the Institute for Wood Technology in Sarajevo, Yugoslavia and is used to get quick information on the toxicity of wood preservatives against house longhorn beetle (Hylotrupes bajulus). The method can be used for superficially treated or deeply impregnated wood blocks, and by using small or normal size test material it can be used as a laboratory or field test, and also for accelerated infestation of test material out of ground contact. The paper is given to the International Research Group on Wood Preservation as a suggested method which could possibly be used as a standard. Only the laboratory test method is described.
Di-sodium fluorophosphate, a new fluorine containing, water-borne wood preservative
1986 - IRG/WP 3373
The physical, chemical properties of Di-sodiumfluorophosphate (Na2PO3F) are compared with those of a trade-mark SF-salt. The opposition of biological activity and toxicological data showed that Di-sodiumfluorophosphate may be a suitable alternative to SF-salts ( based on MgSiF6).
D Seepe, W Metzner
Collaborative experiments in testing the toxicity of wood preservatives to soft rot fungi
1970 - IRG/WP 25
Eight Institutes from seven countries, Austria, England, France, Germany, Holland, Sweden and Switzerland have collaborated in an attempt to assess the suitability of various laboratory test procedures for acceptance as standard methods of determining the toxicity of wood preservatives to the cellulose-attacking micro-fungi which cause 'soft rot' of wood. Pure culture methods with Chaetomium globosum have been tested together with soil burial methods in which the mixed fungus flora of unsterilised local soils has been used as inoculum. The results obtained with a copper/chrome/arsenate preservative have been presented and discussed. It is concluded that the information available is not yet adequate to permit definition of a reliable standard test method. The work has however demonstrated the unsuitability of Chaetomium globosum as a test organism in pure culture tests on softwood and has given indications that soils low in organic matter content may be most suitable for mixed culture tests.
J G Savory, A F Bravery
Eco-tax - A new threat for wood preservation? The Belgian experience
1993 - IRG/WP 93-50001-32
At the end of January 1993, a bill was put for Belgian Parliament related to the introduction called "Eco-taxes" on a series of products, such as packaging for drinks (especially on PVC-bottles), non-returnable articles (shavers, small cameras), batteries, pesticides for non-agricultural use and paper.
G Van Steertegem, F De Jaeger
Potentialities of protein borates as low-toxic, long-term wood preservatives - Preliminary trials
1999 - IRG/WP 99-30212
Boron compounds are efficient wood preservatives, as well as safe for the mammals and environmentally acceptable. Their natural solubility allows them to treat almost any wood species, but is also the cause of their high depletion from treated timber in outside exposure. In order to reduce this leachability, potentialities of proteinic polymer networks retaining boron within the wood have been investigated. Several mixtures of boric acid and proteins (including ovalbumin, collagen, casein, soya flour) have been used to treat pine sapwood miniblocks. The insoluble networks were obtained by protein gelation or coagulation, induced by a physical and/or a chemical factor. These systems appeared to retard boron leaching, the decrease of the leachability rate depending on the protein and the denaturing agent involved in the network creation. The best results have generally been observed for the irreversible heat-induced protein gels. These associations are also able to conserve some boron mobility and activity. Accelerated biological tests of leached wood samples showed good durability performances against Basidiomycetes. The use of protein borates seems to be an interesting basis for low-toxic wood preservatives. Furthermore, in some cases, proteins could add their anti-nutritional factors to boron efficacy to enhance wood protection.
M-F Thévenon, A Pizzi, J P Haluk
Surveillance médicale des personnels exposés aux produits de préservation du bois
1990 - IRG/WP 3588
Standardisation of tests of toxicity of preservatives to soft rot fungi
1978 - IRG/WP 2119
J G Savory
2nd IRGWP - Questionnaire on the state of pollution control in the field of wood preservation (Introductory letter)
1981 - IRG/WP 3184
2nd IRGWP - Questionnaire on the state of pollution control in the field of wood preservation
1981 - IRG/WP 3185
Quelques observations biologiques sur la conduite des essais de protection des bois immerges en milieu marin
1976 - IRG/WP 421
Creosote movement from treated wood immersed in fresh water: Initial PAH migration
2003 - IRG/WP 03-50201
Creosote has a long history of successful use as a wood preservative, but polycyclic aromatic hydrocarbons (PAHs) in this preservative have raised environmental concerns, particularly when creosote-treated wood is used in aquatic environments. A number of models have been developed to predict the risk of creosote use in aquatic environments, but one limitation of these models is a lack of data on the initial rates of creosote migration from treated wood. We examined the effect of flow rates on creosote migration from freshly treated wood immersed in fresh water. Creosote component levels declined to a steady state within 7 days, suggesting that creosote migration decreased sharply after an initial spike. The data will be used to enhance existing predictive models.
Sung-Mo Kang, J J Morrell, J Simonsen, S T Lebow
Potential toxicants for controlling soft rot in preservative treated hardwoods. Part 4: Evaluation of combined diffusion and toxicity
1979 - IRG/WP 2129
A large number of inorganic and organic preservatives were evaluated as potential soft rot control chemicals, by their degree of inhibition of fungal growth after allowing them to diffuse through a 6 mm thick wood slab. The tests were inoculated with wood powder from soft-rotted CCA treated poles. Pentachlorophenol was unable to diffuse quickly through the wood slab, although formulations with hexylene glycol showed some promise. Hydroxyisoxazole gave good results as did a number of other organic materials including "Busan 30", "Busan 52", "Permapruf T", sodium oxinate, sodium trichlorophenate, "Gloquat C", „Hyamine 1622", butyl icinol, and the commercial bandage materials "Osmoplast" and "Wolman pole bandage". Of the inorganic materials tested, good results were obtained with "Basilit BFB", with other Cu-F-B formulations including "Blue 7", and with fluoroborate and fluorosilicate preparations in general. Arsenates also showed some promise.
E W B Da Costa, O Collett
Laboratory experiments on aerial emissions from wood treated with wood stains
1993 - IRG/WP 93-50001-06
Due to the actual environmental interest in wood preservation, a series of experiments was carried out on the emission of biocides from treated wood. The research focussed on the volatilization of 5 biocides from boards treated with wood preservative finishes containing dichlofluanide (DCF) azaconazole (AZA), pentachlorphenol (PCP), iodopropynylbuthylcarbamate (IPCB) and tributhyltinoxide (TBTO). Formulations used were solventborne or waterborne and varried from low build to high build types. Treated samples were exposed in a standard emission column to a conditioned air stream and the emitted gasphase was adsorbed on amberlite xad. The chemical compounds were released in an appropriate solvent and subsequently analysed. A distinct variation was observed between the emission results of the different biocidal compounds. The volatilization values decreased in the following order: TBTO > DCF > IPBC > PCP >> AZA Relating the chemical concentration, obtained under various conditions of test to the inherent toxicity of the preservatives, it can be concluded that azaconazole possesses the lowest aerial toxicity potential. PCP and TBTO are considered to possess a lower aerial safety factor, while dichlofluanide and IPBC take an intermediate position. A significant effect of some of the exposure variables used could be noticed e.g. temperature, application dosis and exposure period. Other variables of importance were type of formulation, pre-curing of coating, moisture content and type of wood. As an overall conclusion, the emission tests gave evidence of no real danger for human inhalation toxicity. In none of the conditions used, for any preservative, the level of emission exceeded the maximal aerial concentration, cited in literature.
G M F Van Eetvelde, M Stevens
N-tritylmorpholine as a potential marine wood protectant against teredinids and pholads - A preliminary evaluation
1983 - IRG/WP 497
The molluscicide, N-tritylmorpholine, is effective in eradicating certain fresh water snails, the intermediate hosts in the transmission of schistosomiasis in man. This preliminary study shows that N-tritylmorpholine is also active against wood-boring marine mollusks. Fine sapwood impregnated with this morpholino compound was not damaged by teredinids or pholads while exposed at two marine sites in Panama. Because of its extreme insolubility, N-tritylmorpholine becomes a very specific toxicant, affecting only those marine mollusks (teredinids and pholads) which bore into the treated wood.
J D Bultman, K K Parrish
Tebuconazole - Efficiacy, toxicity, physical properties
1995 - IRG/WP 95-30093
An overview ahout the physical properties and toxicology of tebuconazole as well as an update of efficacy data of this triazole are given.
Tests on the effectiveness of concentrated borate wood preservative
2009 - IRG/WP 09-30500
Tests were carried out to examine the toxicity of concentrated borate wood preservative to termites, fungi and mammals. The results showed that the preservative treated timber had high resistance to termite or decay and its acute oral toxicity belonged to low grade. The research shows that concentrated borate solution is an environmentally sound preservative and can be used in non-pressure treating.
Su Haitao, Zhang Yanjun, Xie Guijun, Chen Lifang, He Xuexiang
Generic code of good practices for wood protection facilities. Part 1: Wood protection (antisapstain) facilities
1993 - IRG/WP 93-50003
In general, the potential of high toxicity (aquatic and human) of wood protection (antisapstain) chemicals dictates the need to protect the environment and humans from its harmful effects. This document is a compendium of recommendations for the design and operating practices of wood protection facilities. The suggested recommendations focus on achieving the objectives of protecting the environment and workers in a wood protection facility from harmful exposure to wood protection chemicals.
G Das, V N P Mathur
Triazoles: Synergism between propiconazole and tebuconazole
1995 - IRG/WP 95-30092
The synergistic action of the two triazoles propiconazole and tebuconazole against wood rotting fungi can clearly be demonstrated by determination of toxic values according to Standard EN 113. The results show that by combining both triazoles a better balanced spectrum of activity can be achieved. The reduction of the toxic values against the white rot fungus Coriolus versicolor (toxic values of the combination remarkable below the values of the individual active ingredients) proves particularly clear the synergistic behaviour of the combination. Additional trials with such combinations (L-joint-tests, lap-joint-tests, soil block tests) are initiated.
H-U Buschhaus, A R Valcke
Toxicity of etofenprox to the Formosan subterranean termite, Coptotermes formosanus
1994 - IRG/WP 94-30048
Etofenprox is an insecticide with exceptionally low mammalian toxicity. When applied topically to workers of the Formosan subterranean termite, Coptotermes formosanus Shiraki, the LD50 of etofenprox of 4.78 to 6.59 was in the same range as termiticides currently in use. Etofenprox was a relatively quick acting termiticide, with most mortality occurring within 24 hours. In both vertical and horizontal laboratory tunneling assays, etofenprox concentrations as low as 10 ppm reduced termite penetration of crushed coral and silica sand, and consistent protection was achieved with concentrations of 100 ppm or greater. Termites avoided contact with the treated substrate and mortality was generally low, indicating that most termites did not contact the substrate often or long enough to acquire a lethal dose. These results, and the low mammalian toxicity of etofenprox, indicate that it may be useful both as a contact insecticide for injection into active termite infestations within structures, and as a soil insecticide to prevent termites from entering structures. Although more research is required to establish the longevity of etofenprox in the soil under field conditions, our laboratory results indicate that 100 ppm in the soil is a reasonable minimum target concentration for field application.
M Tamashiro, J K Grace, R T Yamamoto
Bioassays for rapid assessment of heavy metal toxicity in seawater
1998 - IRG/WP 98-50112
In evaluating the effect of CCA leachate on the establishment of fouling communities on wood exposed in the sea, three organisms were assessed as biological indicators of heavy metal toxicity. These were two macroalgae, Fucus serratus and Undaria pinnatifida. and the motile protist thraustochytrid, Schizochytrium aggregatum. The choice of these organisms for the tests carried out was based on the need for rapid methodology and relative simplicity in their isolation and cultivation. The two test algae were collected locally on the south coast of England, cleaned of surface contamination and prepared for release of their respective reproductive spore types. Toxic effects of a range of concentrations of CCA leachate were then measured in terms of spore/zygote germination using simple microscopic observations after 3-4 days incubation. The thraustochytrid was obtained from stock cultures held at the University of Portsmouth. The zoosporic stage in the life cycle of this organism was used to indicate the toxic effects of copper ions in seawater-based medium by measuring loss in motility over a 20 minute period. Data were collected using motion analysis equipment. Subsequent recovery of zoospores after 1 hour exposure to different copper levels was determined. Non-motile stages of the life cycle of thraustochytrid isolates were also used to determine copper toxicity. Tolerance of these organisms to heavy metals in CCA leachates will be discussed.
C J Brown, R L Fletcher, R A Eaton
Preservative effectiveness of medium temperature creosote oil
1990 - IRG/WP 3597
Medium temperature creosote oil (MTC) was prepared by removing light naphthalene oil and heavy anthracene oil from the coal tar by means of fractional distillation. We conducted the effectiveness test of MTC in accordance with the JWPA method for testing effectiveness of surface coatings with preservatives against decay fungi. The soil treatment test against Serpula lacrymans was also carried out with Kanuma-soil. Preservative effectiveness of MTC was sufficient for wood against Tyromyces palustris and Serpula lacrymans. The hyphal growth of Serpula lacrymans to the treated layer with MTC from the nutrient one is suppressed in the soil treatment test.
S Doi, A Yamada, Y Suda
Albumin borate: A new non-toxic, wide-spectrum, long-term wood preservative
1998 - IRG/WP 98-30167
Boron, widely recognized for its broad range of activity towards both fungi and insects and for its low mammalian toxicity, can not provide long term protection to treated timber due to its high leachability. Boron, in the form of boric acid, can be partially fixed to timber by the formation of an association with egg albumin, which is insolubilized by heat-induced coagulation. Chemical investigations on fixation mechanisms of boric acid by egg albumin indicated that both acid-base salt formation occurs, as well as the formation of boric acid-albumin complexes, depending on the boric acid/protein ratio. In treated timber, a chance in protein conformation in presence of boric acid, has been shown by scanning electron microscopy. These mechanisms, partly reversible, while greatly retarding its leaching, leave small amounts of boron free to exercice its activity when needed. Boron leaching as a function of time, appears to tend to an equilibrium value, which one differs in the case of an albumin coagulum alone from what is obtained by leaching treated wood samples. Accelerated biolocical tests using such treated timber have shown that albumin borate used as wood preservative has effectiveness against wood decay, and have durability performances comparable to those obtained with CCA.
M-F Thévenon, A Pizzi, J-P Haluk
Traitement des matériaux lignocellulosiques en présence des composés halogénés (Risques toxiques des produits de combustion)
1995 - IRG/WP 95-50040-17
From the point of view of the combustion products toxicity, the highest environmental hazard comes from the combustion of materials creating toxic products such as dioxins and dilbenzofurans. 95% of these are formed during incineration of different materials. The aromatics result essentially from the products of paper industry and from wood treatment. Formation of halogenated products during the combustion of materials on the wood basis (papers, cartons, packing materials, wood treated, et c.) in the presence of halogenated compounds (PVC, PVDC, halogenated salts) is very complex. From the point of view of the toxic products formation, there is necessary to examine not only the influence of the polymer structure and the structure of halogenated compounds, but also oxygen concentration, temperature, ions, radicals and another components present in the flame. For the formation of chlorinated dioxins and dibenzofurans is essential that the polymer is able to generate the compounds with benzoic character as the intermediates. The examples of such precursors can be phenol formaldehyde polycondensates, various types of wood products, some polyesters and epoxy resins, but also polyvinyl chloride and polyvinliden chloride, combustion products of whose are aromatic structures.
I Surina, M Slimak, S Vodny, A Périchaud, K Balog
Summaries of two Russian papers received from Professor Dr. D.A. Belenkov and V.A. Seletskaya of the Ural Forest Engineering Institute, Sibirsky Trakt, 37, Sverdlovsk, USSR, on the toxicity to Coniophora cerebella of salts of hydrofluoric acid and some fluoroborates
1977 - IRG/WP 298
1) Evaluation of the toxicity of some salts of hydrofluoric acid against the house cellar fungus (Coniophora cerebella Schroet) Data are presented on the method of probability evaluation of the toxicity of the fluorides of sodium, ammonium, potassium, zinc and iron. On the retention of fluorine in wood all salts, except iron, possess practically equal toxicity at the standard level of the probability of the protection of the wood - 0.95 . There is good agreement between the analytically and graphically determined dose level. Evidence is given for dose variabitility, probabilities of wood protection at 0.5 and 0.95, the curve of efficacy - activity and the construction of the empirical probit graph. 2) Investigation of the toxicity of some borofluorides towards the house cellar fungus Probability evaluation of the toxicity of borofluorides against the cellar fungus, and probit analysis evidence show that toxicity decreases in the sequence sodium borofluoride, copper borofluoride, tributyltin borofluoride. The effectiveness of protection method is able to evaluate the amount of fluorine and boron required in the wood.