This article page is from a segment of the Metalsmith Magazine (1984 Spring), “Health Hazards”, discussing questions from readers about using sumac and the effects of gas ozone.


Dear Linda,

I frequently enhance my metal objects with wood. I am presently making a chessboard with cocobola and sumac. Are there any dangers in using sumac? Someone said that some people get serious reactions to using cocobolo—could you discuss this and any other woods that might be hazardous to use?

— L.B.

Dear L.B.,

Sumac can produce a contact dermatitis similar to poison oak and poison ivy. Not everyone will react to these plants. I suspect that if you’ve been working with sumac and have not developed any rash or blisters that you are not sensitive to it. Poison sumac is the white-, or ivory-, berried sumac. “One can be poisoned by bruising or tearing the leaves or twigs of this plant (even in winter),” writes William Harlow in his book Trees of the Eastern and Central United States and Canada. Dover Publications, NY, 1957.

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In answer to your other question about poisonous woods: The buckeye seed is Poisonous. but not the wood, or bark; greenhart is poisonous if it gets into your skin through cuts or splinters; redwood dust should not be inhaled, it can severely affect the respiratory system causing symptoms similar to pneumonia, with repeated exposures resulting in lung scarring and decreased lung capacity. Redwood splinters can be extremely more reactive than other wood splinters, also. Some other woods that might cause skin reactions, allergic dermatitis similar to poison oak or poison ivy, are South American Boxwood, mahogany, birch and dogwood. It depends on the individual and the type of exposure, contact dermatitis does not occur the same way in every individual. Pages 54-67 of Work is Dangerous To Your Health by Jeanne Stellman, Ph.D. and Susan Daum, M.D., published by Vintage Books, 1973, has a very good description of skin reactions and diseases.

According to an article by Michael McCann in the October/November 1982 Art Hazards News. there is increasing evidence that prolonged exposure to wood dusts may cause several types of cancer—nasal cavity and nasal sinus. These cancers appear to be more prevalent in woodworkers than the general populace and more prevalent with the use of hardwoods than softwoods. There has not yet, to my knowledge, been sufficient studies about those who work with softwood.

Other research is investigating what diseases and conditions are resulting from pesticides and preservatives used in treating the woods. These may antagonize the respiratory system, eyes and mucous membranes.

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Cocobola is very toxic—it can produce skin reactions, respiratory difficulties, and has been suspected of triggering nervous/emotional disorders. If you think you are having adverse reactions or symptoms from any material that you are working with, try a few preventative measures: wear work gloves, long sleeve shirts and other suitable clothing to prevent skin contact, protect eyes, nose and throat from dust with appropriate ventilation and respirators. Avoid carrying toxic dusts on your work clothes from your studio into your living environment.

If you do get a severe skin reaction, and you think it is from some material that you work with, go see a dermatologist with a list of what you think is causing the reaction. This will assist in determining proper treatment and preventative measures to avoid recurrence. lf the doctor seems skeptical, call your local OSHA office and ask for a recommendation of a doctor who specializes in occupational skin or respiratory disease.

By developing a few precautionary work habits, you should be able to continue working with the woods you like without developing health problems.

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Dear Linda:

Could we see something about the gas ozone: 1) The Toxic effects it has; 2) possible liberating of ozone caused by arcing in electric motors such as those found in flexible-shaft machines used by jewelers; 3) means of protection and/or remedies. —Bernard Bernstein

Dear Bernard:

Michael McCann in Art Hazards News (July 1982) replies: Ozone is a gas with a pungent odor which is a very powerful lung irritant. In large amounts it can cause chemical pneumonia although that is not likely to occur from arcing in electric motors. Long-term exposure to low levels of ozone can cause chronic bronchitis, emphysema, lung scarring and premature aging of lung tissue.

Ozone can be released whenever arcing occurs. The most likely cause of this arcing is worn brushes in the motor, although some arcing will occur even normally. lf you are using these power tools for extended periods of time, I would recommend exhaust ventilation for the room to reduce the ozone levels. If arcing is excessive, then you should have the motor checked for possible repairs.

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Another problem that is common with power tools is lack of proper grounding. This could result in severe electrical shocks. Power tools should always be grounded. Even better protection can be obtained by installing a ground fault interrupter which will shut off the power if a short circuit occurs.