A book providing an overview of the various wood and tree fungi that damage trees, lumber, and timber. Special focus is given to identification, prevention, and remediation techniques, and the book ...bridges the gap between research and application.
Wood is an environmentally friendly material for the construction of buildings, and it possesses great physical and mechanical properties. However, under certain circumstances, it needs to be ...protected from degradation. This can be achieved either by proper design or treatment. In this study, eastern white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) were impregnated with propiconazole and 3-iodo-2-propynyl butylcarbamate, which are two organic fungicides. Unlike most impregnation techniques, no pressure treatment was needed. Instead, an aqueous buffered amine oxide system was used to allow the fungicides to diffuse rapidly into the wood. Many combinations of fungicides and amine oxides, as well as different diffusion times were tested to study the effect of the treatment on the dimensional stability and resistance to decay fungi. It was found that only the amine oxide affected the dimensional stability of the treated wood, with anti-swelling and anti-shrinking efficiencies values up to 30%. Amine oxides and fungicides both had an impact on the weight loss caused by the brown rot fungi. The weight loss after 10 weeks of exposure to Rhodonia placenta was reduced by half when using amine oxides or fungicides, and it was completely inhibited when they were combined.
Cedarwood oil (CWO) has a wide range of bioactivities, including insect repellency and toxicity, as well as conferring resistance against termites and wood-decay fungi. In previous work examining ...pressure treatment of wood, ethanol was used as the diluent/carrier for CWO. However, it is preferable to use a water-based carrier for environmental, safety and cost considerations. In this research, we describe the use of a hexadecyl ammonium chloride amylose inclusion complex/polyvinyl alcohol (AIC/PVOH) as an emulsifier for CWO to pressure treat wood. Wood samples were subsequently tested for resistance to termites and four species of wood-decay fungi. Wood was also compared for water absorption and swelling. In the termite test, the lowest wood mass losses were for the AIC/PVOH/CWO (5.4%) and EtOH/CWO (5.4%) treatments, which also had the highest termite mortalities (i.e., 100% and 97.6%, respectively). In general, for wood-decay fungi, wood mass losses were lowest for the EtOH/CWO and AIC/PVOH/CWO treatments and were highest for the Water, EtOH, and AIC/PVOH treatments. Wood blocks treated with AIC/PVOH repelled water as evidenced by higher contact angle, lower mass gain (both by submersion and water saturation) and lower swelling. The results indicated that the amylose inclusion complex makes an excellent emulsifier and the AIC/PVOH/CWO mixture inhibits both termites and wood-decay fungi. The amylose inclusion complex alone was as inhibitory as CWO against termites and also inhibits both water absorption and swelling in treated wood.
•An amylose inclusion complex was used with cedarwood oil to treat wood.•Mass loss due to termites was lowest for the amylose/cedarwood oil treatment.•Mass loss due to wood-decay fungi was lowest for the amylose/cedarwood oil treatment.•The amylose complex inhibits water absorption, holding capacity and swelling by wood.•An aqueous dispersion of CWO and amylose inclusion complex improved wood properties.
Chemical compounds of wood preservation from plants vary and are not known specific to the species. Chemical analysis of plants is responsible to ensure active compound in natural extracts wood ...treatment. There are many sources of natural extracts found in Indonesia that were explored for wood preservatives chemicals. They are bark of acacia and alstonia, leaves of orthosiphon and azardirachta and Dioscorea tubers. The present study was aimed at investigating the variation of the chemical constituent of natural extracts material of wood preservative through GC-MS analysis. Five natural extract sources were acacia bark (Acacia spp.), pulai bark (Alstonia scholaris), kumis kucing leaves (Orthosiphon spp.), mimba leaves (Azardirachta indica), and gadung tubers (Dioscorea spp.). Two non-polar solvents, i.e., n-hexane and petroleum ether were used for five natural source extractions following ASTM soxhlet extraction. The research showed that triterpene and fatty acid derivatives were the major compounds present in five natural extracts. They were lupeol; 7,22-Ergostadienone; Lup-20(29)-en-3-one; Lup-20(29)-en-3-ol, acetate, (3.beta.)-; urs-12-en-3-one; ethanol,2,2-diethoxy-; stigmasta-5,22-dien-3-ol, acetate,(3.beta.)-; 5H-3,5a-Epoxynaphth(2,1-c)oxepin, dodecahydro-3,8,8,11a-tetramethyl-; linoleic acid; naphthalene, 1-methyl-. These compounds have been assigned as the possibly responsible to against termites or fungi.
In this work, a method is proposed for increasing the operational properties of wood by treating it with organomineral compositions based on arabinogalactan and silica. Scots pine (Pinus silvestris) ...was chosen as the object of the study. Three different treatments were used. One treatment was a pure aqueous solution of arabinogalactan, the second and third were compositions based on aqueous solutions of arabinogalactan with 5% and 10% (by weight) addition of highly dispersed silica, respectively. Arabinogalactan was used as a surfactant for silica nanoparticles and also as a film-forming agent. The hardness of the wood surface increased by 1.2-2.3 times and compressive strength along the fibers increased by 20-45% after treatment with an organic-mineral composition. Treatment with impregnating compositions did not lead to a significant decrease in moisture absorption and swelling.
Late prehistoric and early historic communal hunting sites along the southwestern mountainous margins of the Great Basin, United Sates, include timber-built corral-traps estimated to be only a few ...hundred years old. In most of these, no animal bones or direct evidence for the targeted species were found in the corrals. Our goals were to characterize and reconstruct past use of these sites, and we chose two distinct case studies, Anchorite Pass and Excelsior. We provide high-resolution documentation of the sites and their archaeological components, using nearly 10,000 aerial photographs as the basis for 3D modeling. We specifically address construction characteristics which include the incorporation of living trees and felling juniper timbers by fire. Drawing on limited ethnographic sources and current seasonal routes of local mule deer herds, we suggest the two sites were used for seasonal trapping of such herds. Forest fires and modern construction severely endanger such vulnerable sites.
Radiata pine is the main wood species used in the Chilean construction industry, but it must be protected due to its low natural durability. Chemical protection of wood by impregnation allows for a ...more efficient utilization of the forest resources by extending its useful life. The use of nanoparticles in wood protection has garnered great interest during the last decade, due to their unique physicochemical properties, different from those of larger sized materials. In this research, the impregnation of radiata pine wood with copper nanoparticles (CuNP) was studied in terms of retention, penetration, leaching, and its protective effect against wood rot fungi growth according to EN 113, AWPA A3-91, A9-18, and E11-16. Penetration analysis confirmed a uniform distribution across the wood, with total penetration in the impregnated samples with the highest concentration solution of CuNP. Retention values of the impregnated wood increased proportionally with the concentration of nanoparticles evaluated by EDXRF. Leaching analysis showed copper removal during the first hours of the test, with a constant leaching rate up to 144 h. Impregnated wood mass loss (ML) due to exposure to Gloeophyllum trabeum and Rhodonia placenta fungi were significantly reduced regardless of the CuNP concentration or fungi tested, with an ML smaller than 5% and smaller than 14% for leached samples.
Human Health Effects From Chronic Arsenic Poisoning-A Review KAPAJ, SIMON; PETERSON, HANS; LIBER, KARSTEN ...
Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering,
10/2006, Volume:
41, Issue:
10
Journal Article
Peer reviewed
The ill effects of human exposure to arsenic (As) have recently been reevaluated by government agencies around the world. This has lead to a lowering of As guidelines in drinking water, with Canada ...decreasing the maximum allowable level from 50 to 25 μg/L and the U.S. from 50 to 10 μg/L. Canada is currently contemplating a further decrease to 5 μg/L. The reason for these regulatory changes is the realization that As can cause deleterious effects at lower concentrations than was previously thought. There is a strong relationship between chronic ingestion of As and deleterious human health effects and here we provide an overview of some of the major effects documented in the scientific literature. As regulatory levels of As have been decreased, an increasing number of water supplies will now require removal of As before the water can be used for human consumption. While As exposure can occur from food, air and water, all major chronic As poisonings have stemmed from water and this is usually the predominant exposure route. Exposure to As leads to an accumulation of As in tissues such as skin, hair and nails, resulting in various clinical symptoms such as hyperpigmentation and keratosis. There is also an increased risk of skin, internal organ, and lung cancers. Cardiovascular disease and neuropathy have also been linked to As consumption. Verbal IQ and long term memory can also be affected, and As can suppress hormone regulation and hormone mediated gene transcription. Increases in fetal loss and premature delivery, and decreased birth weights of infants, can occur even at low (<10 μg/L) exposure levels. Malnourished people have been shown to be more predisposed to As-related skin lesions. A large percentage of the population (30-40%) that is using As-contaminated drinking water can have elevated As levels in urine, hair and nails, while showing no noticeable clinical symptoms, such as skin lesions. It is therefore important to carry out clinical tests of As exposure. Factors combining to increase/decrease the ill effects of As include duration and magnitude of As exposure, source of As exposure, nutrition, age and general health status. Analytical determinations of As poisoning can be made by examining As levels in urine, hair and toenails. Communities and individuals relying on groundwater sources for drinking water need to measure As levels to ensure that their supplies are safe. Communities with water As levels greater than 5 μg/L should consider a program to document As levels in the population.
The objective of the study was to investigate the impact of chopped wheat straw (CWS), ground corn cobs (GCC) and commercial pellets (CP), as inoculum carriers, on both growth and polycyclic aromatic ...hydrocarbons (PAH) degradation performances of
Dichomitus squalens,
Pleurotus ostreatus and
Coprinus comatus. A historically-contaminated soil (HCS) and creosote-treated shavings (CTS) from the Soběslav wood preservation plant, characterized by different relative abundances of the PAH bioavailable fractions, were used to assess the contaminated matrix effect and its interaction with both carrier and fungal strain. In HCS, best results were obtained with CP-immobilized
P. ostreatus, which was able to deplete benzoaanthracene, chrysene, benzobfluoranthene (BbF), benzokfluoranthene (BkF) and benzoapyrene (BaP) by 69.1%, 29.7%, 39.7%, 32.8% and 85.2%, respectively. Only few high-molecular mass PAHs such as BbF, BkF and BaP were degraded beyond their respective bioavailable fractions and this effect was confined to a limited number of inoculants. In CTS, only phenanthrene degradation exceeded its respective bioavailability from 1.42 to 1.86-fold. Regardless of both inoculum carrier and fungal species, degradation was positively and significantly (
P
<
0.001) correlated with bioavailability in fungal microcosms on HCS and CTS and such correlation was very similar in the two matrices (
R
adj
2
equal to 0.60 and 0.59, respectively). The ability of white-rot fungi to degrade certain PAHs beyond their bioavailability was experimentally proven by this study. Although CTS and HCS considerably differed in their physico-chemical properties, PAH contents and contaminant aging, the relationship between degradation and bioavailability was not significantly affected by the type of matrix.
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