Red cedar wood

It is puzzling that this risk from smoking is not seen in all chemical exposures that cause occupational asthma. For example, a large series of 232 patients with asthma caused by western red cedar wood (in which the causal agent is believed to be plicatic acid) contained only 5 per cent of current smokers (Chan-Yeung et al., 1987). This is similar to isocyanate-induced... 

Thujic add Red cedar wood Thuja plicata Donn T. monitor pupae Injection Sllpg 111... 

A few acid woods, such as oak, chestnut and Western red cedar, accelerate surface weathering of aluminium, but do not usually give rise to serious attack . Timber preservatives containing soluble copper compounds should be avoided creosote and zinc napthenate are satisfactory preservatives for wood in contact with aluminium. 

Zinc in contact with wood Zinc is not generally affected by contact with seasoned wood, but oak and, more particularly, western red cedar can prove corrosive, and waters from these timbers should not drain onto zinc surfaces. Exudations from knots in unseasoned soft woods can also affect zinc while the timber is drying out. Care should be exercised when using zinc or galvanised steel in contact with preservative or fire-retardant-treated timber. Solvent-based preservatives are normally not corrosive to zinc but water-based preservatives, such as salt formulated copper-chrome-arsenic (CCA), can accelerate the rate of corrosion of zinc under moist conditions. Such preservatives are formulated from copper sulphate and sodium dichromate and when the copper chromium and arsenic are absorbed into the timber sodium sulphate remains free and under moist conditions provides an electrolyte for corrosion of the zinc. Flame retardants are frequently based on halogens which are hygroscopic and can be aggressive to zinc (see also Section 18.10). 

Smith, R. S., Johnson, E. L. and Cserjesi, A. J., Corrosion of Zinc-Coated Nails Used with Preservative-Treated Western Red Cedar Shakes in Service. Document No. IRG/WP/ 3197, International Research Group on Wood Preservation, Stockholm (1982)... 

Wood dust (particularly red cedar) Many Irritation Eyes, mucous membranes, Sensitizaton Asthma Moderate (N/A)... 

One way to avoid the use of any preservative is to use wood that is naturally resistant to decay. The heartwood of more naturally rot-resistant species, such as oak, can be used untreated. Other woods that last well without treatment are larch, which will last about 10 years in contact with the soil, or up to 20 years if not in contact with soil Western red cedar, which will give service for about 20 years and sweet chestnut, traditionally used for fence palings and posts. Untreated pine lasts for about five years. Well-seasoned wood that has been allowed to dry out evenly is more expensive than greenwood (freshly cut undried wood), but in its favor, it tends to last longer and can be less prone to distortion as it weathers. 

Primary irritant dermatitis caused by wood contact consists of erythema and blistering, which may be accompanied by erosions and secondary infections. Irritant chemicals typically are found in the bark or the sap of the outer part of the tree. Therefore, loggers and persons involved in initial wood processing are most affected. In most reports of contact dermatitis, hardwoods of tropical origin have been implicated, although other woods, including pine, spruce, western red cedar, elm, and alder, have been cited. 

Virginia cedarwood oil is produced by steam distillation of sawdust, finely chipped waste wood from the manufacture of cedarwood products, or from stumps and logs of the red cedar Juniperus virginiana L. (Cupressaceae). It is a light yellow to pale brown, viscous liquid with a characteristic cedarwood odor. The oil sometimes solidifies at room temperature. 

Some bentwood projects are done over a period of time, as materials become available, and some objects may include more than one type of wood. Trees commonly used as sources for bentwood include ash, aspen, bald cypress, birch, cottonwood, box elder, dogwood, red cedar, maple, hickory, and different species of fruit trees. Some vines, such as honeysuckle, wisteria, and rattan vine (.Berchemia scandens) are also used. 

Perhaps the most extensive area of research in simple pretreatment systems to enhance the weathering properties of wood has involved application of inorganic salt solutions. Much of the early work in this field was undertaken at the U.S. Forest Products Laboratory in Madison, Wisconsin and was aimed at improving the performance of transparent finishes. Black [25] described an experimental chromate-based wood finish and Black and Mraz [26] discovered that both acid and ammoniacal-copper chromate treatments significantly improved the performance of clear finishes on western red cedar, redwood (Sequoia sempervirens), and Douglas fir plywood. Later research [27] demon-... 

While many case reports and epidemiologic studies on asthma associated with wood dusts have been published. Western red cedar is the most notable and is the only one that has been studied extensively and has dose-response information available. 

Tetrachloroethane (1,1,2,2-) Acetylene Tetrachloride Tetrachloroethane Chlorotrifluoroethylene Trifluorochloroethylene Trifluorovinylch bride Methacrylic Acid Methyl Acrylic Acid Dichloroacetic Acid Nitropropane (2-) Cam phene Hexene Noryl GFN3 Cumene Hydroperoxide Bromobutyric Acid (2-) Methyl Methacrylate Cedar Wood Oil Lavender Oil Terpineol Eucalyptus Oil Tung Oil Sunflower Oil Soybean Oil Linseed Oil Cottonseed Oil Corn Oil Coconut Oil Benzalkonium Chloride Zephiran Chloride Creosote Cod Liver Oil Ceresin Castor Oil Bone Oil Pine Oil Rapeseed Oil Spermaceti Sperm Oil Tall Oil Cocoa Butter Red Oil Turkey Red Oil Neats Foot Oil Johnsons V fex 111 Palm Oil Vidden D Dowtherm Dowtherm A Lanolin Sassafras Oil Sandalwood Oil Santal Oil Rose Oil Nutmeg Butter Nutmeg Oil Cedar Leaf Oil Terpinyl Acetate Coal Tar Tar... 

The presence of polyphenols and tannins in woods such as oaks, western red cedar, eucalypts and Nothofagus sp. leads to blue-black tannin stains during sawing of moist timber, or in the grain around metallic wood fastenings when the wood remains moist. 

CHAN-YEUNG, M. (1993) Western red cedar and other wood dusts, in BERNSTEIN, I.L., CHAN-YEUNG, M., MALO, J.-L. BERNSTEIN, D.I. (Eds) Asthma in the Workplace, pp. 503-531. New York Marcel Dekker. 

The wood mostly used for making pencils is that of red cedar, not the cedar of Lebanon, but the Junip rus Virginiccna which grows in Florida, Alabama, and Tennessee, and lends itself well to the purpose on account of its soft character and straightness of grain. It is usually cut into short thin... 

Southam, C. M., Erlich, J. (1943). Effects of extracts of western red-cedar heartwood on certain wood-decaying fungi in culture. 

Wood wastes do sometimes contain substances that are toxic to plants. In the studies with the 28 species of trees, Allison (1965) reported that most of the woods and barks were not toxic, but California incense cedar and white pine bark were very toxic to garden peas even at the rates of 1 and 2% added to soil in the presence of adequate nitrogen and lime. The woods of red cedar, Ponderosa pine, and loblolly pine, and the barks of California incense cedar and yellow poplar were slightly toxic at the 2-4% rates. The toxicity symptoms usually decreased with time during the two- to three-month period following addition to the soil. There have also been reports that a few other woods, such as walnut, hemlock, fir, and balsam are sometimes, but not always, toxic. Toxicity seems to vary with the age of the tree, and is also dependent upon the quantity added and the test plant. Decomposition time curves, reported by Allison, indicate that it is not uncommon for wood products to slightly retard early decomposition, apparently until the toxic materials disappear. The chemical nature of any toxic products present is not known with certainty but some investigators have attributed the toxicity to resins, turpentine and tannins. 

Synonyms/Trade Names Hard wood dust, Soft wood dust, Western red cedar dust ... 

Wood dust (all wood dusts except Western red cedar) TWA 5 mg/m, ST 10 mg/m ... 

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