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WoodSense Toxic Protect yourself from the health issues caused by dust and some woods.

By Larry Osborn

While the precautions you take around The Usual Suspects workshop machinery have served you well and kept your environment accident free, you could individual wood species. For just about every be ignoring another hazard that has a way of woodIt’s dif�icult in use, to somebody rank the reactionshas reacted and to risks it. In offact, sneaking up on you, that of so-called toxic woods. Some of your favorite woods have varying levels of can cause respiratory problems. The OSHA Wood toxicity, and people can develop certain unpleasant signi�icant, long-term exposure to any wood dust reactions and symptoms from them. Some are limits for wood dust. The exposure limits immediate, and some can develop over time. Some areDust the Standard same for speci�ies all species, workplace exposure and are minor, but some can be downright serious. , domestic or imported, with one The reactions stem from chemical compounds exception. Because of the number of people in wood that come in contact with the skin, eyes, who have reacted to western red cedar, the throat, nose, and respiratory tract, either through allowable exposure limits are half of that direct contact from handling and use or with wood allowed for other species. Beyond that point, dust serving as the delivery system. I’ll cover some we depend on history and the experiences of the species to watch for, the types and severity of others to identify the troublemakers. The of reactions, and strategies you can adopt in the 28 listed at right stand out for the allergic shop to minimize health risks and exposure. reactions and symptoms they have caused.

64 woodcraftmagazine.com June/July 2012 Watch List Species Symptoms/Risks D D Blackwood, African D Brazilian ”cherry”, jatoba A M Bubinga D Cedar, western red D A M Zebrawood Cedar, Spanish D Cocobolo D DM Ipe, Brazilian “walnut” D A G Iroko, African “” DMGG , African DM Mahogany, American D Padauk Makore, African “cherry” DM Mansonia, African “walnut” D A MGG Olivewood D A M Padauk D A Pine, many species D A Purpleheart D A D Cedar Rosewood substi tutes D D Sati nwood (Ceylon) D Sati nwood (West Indian & African) D Walnut Teak (true teak) D Walnut D A Wenge D A Zebrawood A

Key: D = Dermati ti s A = Asthma & Respiratory M = Mucosal Irritati on, Eyes & Nose G = General Symptoms Purpleheart

It’s a fact that… Wood toxicity can run within botanic families. In some wood species a parti cular chemical compound has been identi fi ed as the cause of most reacti ons to that wood. Someti mes that chemical is also found in other, related species. In various “rosewoods,” for example, the species from around the world and some related woods in the same family of trees such as Machaearium scleroxylon, which is sold as Bolivian rosewood, pau ferro, morado, Wenge santos rosewood and other market names, have the same chemical that is known to cause reacti ons. Also related are purpleheart ( paniculata), the padauks and sandalwoods (Pterocarpus spp), and wenge (Milletti a spp).

Opener: Jim Osborn; Wood samples: Shayne Hiles June/July 2012 woodcraftmagazine.com 65 WoodSense

Toxic Wood and Wood Dust Exposure Areas Eyes Bare skins neck and face Sinus Cavity Larynx Oral cavity Tracea Throat Bronchi Bare skin on Lungs arms and hands

Symptoms and Risks Wood toxicity and the chemicals that cause of the mucous membrane of the nose), bronchial it divide into several broad, potentially asthma, and allergic contact dermatitis. The most overlapping categories. Here’s the breakdown: common wood-related health problem is allergic reactions of the skin (contact dermatitis). Irritants These are chemical substances in wood that irritate Toxic exposed areas of the body on some people. Common Dangerous and sometimes lethal substances are reactions such as sneezing, coughing, breathing found in some woods. The potential hazard is problems, and skin rashes can occur almost usually limited to situations where the manner immediately, and the severity is proportional to the of use exposes you to an accumulation of the level of exposure. The symptoms are temporary. toxin. As with irritants, this can even be a hazard for the person using the wood object, such as a Sensiti zers salad bowl or even a wood musical instrument. Here, chemical substances in wood can, after repeated exposure, cause the development of an Carcinogens allergic reaction in susceptible individuals. The Long-term exposure to wood dust can cause cancer potential risk depends not just on the wood, but of the nasopharynx, which may develop in full- also on the level and frequency of exposure, as well time woodworkers after several decades of steady as a person’s sensitivity to developing allergies. Sensitizers are more serious than irritants because also a slightly increased risk for some other serious of the time delay before symptoms develop, and diseases.unprotected Those contact who withwork �ine with wood wood dust. occasionally There is the escalating severity of the reactions. Over time, are far less likely to develop these diseases.

they66 canwoodcraftmagazine.com lead to allergic rhinitis June/July (in�lammation 2012 Healthy Shop Strategies A home shop needs strategies for reducing exposure to wood dust. Consider the measures below for maximum protection. Minimize shop dust First and foremost, do everything possible to collect dust where it’s generated, before it becomes airborne. The primary method for controlling directly from the itself. This can be in the form�ine wood of a shop dust vacuum is with localizedfor benchtop dust machines collection and portable power to a whole-shop dust- collection system that draws from all the major machines via ductwork and hoses. (See “Small- Shop Dust Collection,” June/July 2009 issue, pages

46-53.) Equipped with high-ef�iciency particulate fromair (HEPA) heavy 1- makers to 2-micron (the tablesaw, �ilters, such for instance),systems Use protecti ve clothing and appropriate gear butnot onlythey collectcan also chips, cleanse , and recirculate and �ine dust the air. to minimize exposure to wood dust. Important here is emptying the debris containers Minimize skin contact To minimize contact with troublesome woods and andDowndraft cleaning thetables �ilters also regularly help contain for maximumdust when wood dust, you need to protect or reduce exposed usingef�iciency portable and tosanders prevent on dust smaller from parts. recirculating. Perhaps the skin areas. Wear long sleeves, long pants, hat, cheapest way to maintain clean air is to ventilate the face shield, and (when possible to do so safely) shop with window fans. If you’re fortunate to have gloves, especially when working with reactive a garage shop and pleasant weather, throw open woods known to cause dermatitis. Consider the doors when performing dust-generating work. disposable coveralls for layered protection. Minimize dust inhalati on Play defense with safe practi ces Cheap and commonly used disposable face Finally, clean yourself and your work area masks provide only minimal protection from frequently to minimize dust accumulation and exposure. Use a vacuum to collect dust rather leak and fog up glasses. For a little more money than compressed air to blow dust off work the inhalation of �ine airborne dust. They tend to surfaces, tools, and clothing. At the end of a reusable masks equipped with an exhale valve woodworking day, change out of your dusty (FastCapand better MXV protection dust mask, (95%), Woodcraft buy tighter #836875, �itting 10/ clothes and shoes, and take a shower. I pkg. $18.99). Respirators with replaceable �ilters About Our Author signi�icantly improve protection (99.9%), while Larry Osborn serves as an beoffering uncomfortable a still better during �it (MSA prolonged half-face use respirator, and in wood technology consultant warmWoodcraft weather. #141621, Too, both $29.99). masks However, and half-face they can style for Woodcraft Magazine. In his respirators only keep dust out of your nose and day job, he works as a wood mouth. A full-face style respirator keeps dust out of science and uti lizati on specialist, your eyes as well. Top-end models feature battery- as well as a wood anatomy and identi fi cati on specialist, at the Appalachian keeping dust off your face, hair, and neck (Trend Hardwood Center at West Virginia University. powered �iltered air circulation inside the mask,

AirshieldSanding photo: Pro, Jim Osborn; Woodcraft Illustrati on: #152709, John Hartman $409.99). June/July 2012 woodcraftmagazine.com 67