Wood toxicity

Although both toxic and nontoxic chemical treatments have been extensively studied for protecting wood, the former is still the dominant method for preserving wood. Toxic preservatives in wide commercial use have been subjected to public criticism, so that there is a strong demand for the development of low-toxicity alternatives or safer nontoxic treatments. Nontoxic treatments such as chemical modification will be more and more important for wood preservation because they yield no risk of hazard to health or the environment in the use of endproducts. 

CH3OH Methanol Methyl alcohol, wood alcohol 65 Originally from distillation of wood. Toxic, used to denature ethanol for industrial use. Used as a fuel additive. Miscible with water. 

Medicinal creosote is a mixture of phenols, chiefly guaiacol and creosol (4-melhyl-2-meth-oxyphenol), obtained by distillation of wood tar. B.p. 480-500 K. It is almost colourless with a characteristic odour and is a strong antiseptic, less toxic than phenol. 

In fires, melamine—phenolic laminates ignite slowly at high temperatures and bum slowly producing smoke that has about the same toxicity as wood smoke (17). 

Also, wood fuel is low in sulfur, ash, and trace toxic metals. Wood-fired power plants emit about 45% less nitrogen oxides, NO, than coal-fired units. Legislation intended to reduce sulfur oxides, SO, and NO emissions may therefore result in the encouragement of wood-burning or cofiring wood with coal. 

The fumes of zinc chloride are highly toxic and can damage mucous membranes and cause pale gray cyanation. It can also ulcerate the skin of workers using it as a soldering flux or those handling wood impregnated with it (59). 

Occupational hygiene and health surveillance at industrial timber pre-treatment plants Toxic woods... 

Phenolic-neoprene contact cements are used for structural metal-metal bonding. especially where fatigue resistance and low temperature performance are important [209]. They are also used for bonding textiles, wood, rubbers, plastics, ceramics, and glass to metal and to one another. Solvent toxicity and flammability has greatly reduced the use of contact cements in the wood products industry. Water-based contact cements persist, but generally do not perform as well as the solvent systems, thus allowing market erosion by alternative binders. 

Chemical Reactivity - Reactivity with Water Reacts violently, forming corrosive and toxic fumes of hydrogen bromide Reactivity with Common Materials Attacks and corrodes wood and most metals in the presence of moisture. Flammable hydrogen gas may collect in enclosed spaces Stability During Transport Stable if protected from moisture Neutralizing Agents for Acids and Caustics Hood with water, rinse with dilute sodium bicarbonate or soda ash solution Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Use of some biomass feedstocks can increase potential environmental risks. Municipal solid waste can contain toxic materials that can produce dioxins and other poisons in the flue gas, and these should not be burned without special emission controls. Demolition wood can contain lead from paint, other heavy metals, creosote, and halides used in presen a-tive treatments. Sewage sludge has a high amount of sulfur, and sulfur dioxide emission can increase if sewage sludge is used as a feedstock. 

Ethanol, CH3CH2OH (4), the alcohol of beer and wine, is an ethane molecule in which one H atom has been replaced by an —OH group, and CH3OH (5) is the toxic alcohol called methanol, or wood alcohol. 

Write the complete Lewis structure for each of the following compounds (a) formaldehyde, HCHO, which as its aqueous solution formalin is used to preserve biological specimens (b) methanol, CH3OH, the toxic compound also called wood alcohol (c) glycine, H2C(NH2)COOH, the simplest of the amino acids, the building blocks of proteins. 

Wood, J. (1974). Biological cycles for toxic metals in the environment. Science 183,1049-1052. 

Huling SG, Pope DF, Matthews JE, et al. 1995. Wood preserving waste-contaminated soil Treatment and toxicity response. In Hinchee RE et al., ed. Bioremediation of recalcitrant organics. Columbus, OH Battell Press, 101-109. 

MUF resin is widely used as an adhesive in wood industries, coating technology, paper industries and a main material in kitchenware production. In various applications, different resin properties are needed to suit its application. Important resin properties are for example higher resin solubility, low curing period with lower temperature and catalyst amount, good stability for longer shelf life, and lower free formaldehyde emission, as formaldehyde is very toxic, and can cause cancer [1]. One of the factors that affecting the MUF resin properties is the mole composition. The mole composition is a ratio of formaldehyde to amino compoimd... 

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