FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

[USE WD-40 TO LUBRICATE METAL PARTS, NOT ARTHRITIC JOINTS!]

Question: "I have watched as my co-workers spray a product called WD-40 on their elbows and other places to relieve sore, aching symptoms. If this works, as they tell me it does, then this means that WD-40 penetrates the skin. And, if this is so, then is WD-40 a health threat or possible carcinogen? "My concern is not only my personal risk, but the public at large. I use this product extensively to keep my tools clean and lubricated. It works wonders on door hardware and locks. It also gets on your hands a lot."

Answer: The product, WD-40, has been sold in its familiar aerosol can for years. It is available almost anywhere, even my local grocery store. As has happened with many common products, people try them in ways that the manufacturer never intended. In the case of WD-40, a great myth developed about its benefits in treating arthritis. It is easy to follow the flawed logic: WD-40 works wonders on stiff door locks, squeaky hinges, and rusted bolts. Therefore, it should make my stiff, sore, squeaking arthritic joints work better. Unfortunately, like all myths, this one isn't true.

Your logical assumption that WD-40 would need to penetrate the skin to bring relief from arthritis is correct. And this petroleum based product can be absorbed through the skin to a small degree. The greater the exposure - that is, the more that is on you and the longer it is on you - the greater the amount absorbed. Thin skin, such as that of the face, absorbs more than does the thick skin on the hands. Most people have no reaction to WD-40, but problems ranging from mild skin rashes to significant allergic reactions have occurred.

A potentially more serious exposure occurs from breathing the vapor of WD-40 or of any similar product. The aerosol spray fills the air in the vicinity of where it is used with a cloud of particles. These can easily be inhaled. The delicate linings in the nose, throat and lungs are more susceptible to injury than is the skin. Therefore, there is a greater risk of causing health problems.

Most refined petroleum-based products have a low risk of causing cancer when they are applied to the skin. In fact, they are often used as the base for creams and ointments. I could not find a scientific test of WD-40's cancer-causing potential. The manufacturer's literature doesn't list a specific risk for cancer either, but it does advise against skin or respiratory exposure.

The risk of health problems from WD-40 use are small. Therefore, I'd do what the manufacturer recommends - use it to lubricate and clean, but try to keep it off your skin. That means washing your hands when you've gotten some on you, not just wiping them dry on a rag. Also avoid breathing any of its vapors. If you develop any rash of other health problems, stop using it until you can see your doctor.

Your unasked question is why do people claim they have relief from their arthritis with use of WD-40. For the same reason copper bracelets and magnetic shoe inserts are sold for the purpose. Arthritis is a chronic disease that medical science has yet to cure. The belief and hope that a treatment will help goes a long way toward actually bringing a measure of relief - relief that conventional medical therapy is unable to provide.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.