The deposits in your chimeny contain some nasty stuff. See below. While your chance of contracting testicular cancer from an occasional cleaning are low, they are not zero. I advise anyone who decides to do this on your own to take necessary precautions to limit yourself to exposure of the stuff you knock free.
Also, don't fall off the roof.
My patient is a 39-year-old man who is a professional chimney sweep. He asked me if he should be getting chest x-rays or pulmonary function testing on any kind of a regular basis. Other than increased risk for scrotal cancer, I can't find anything listed for this occupation. What screening tests would you recommend?
Rick Davis, MD
Chimney sweeps are exposed to numerous hazardous chemicals in their daily work. They contact and inhale by-products of fossil fuel combustion, polycyclic aromatic hydrocarbons, carcinogenic metals (arsenic, nickel, chromium), carbon, etc. The study paper on the health of the sweep, cited by Gustavsson,[1] was published in 1775. This report was the first ever to identify an occupational cancer, in this case, an increase in the risk for scrotal cancer.
The best contemporary studies come from Sweden, where a large chimney sweep guild with good health records provides reasonable data.[1] Several studies have shown that chimney sweeps have a higher risk for malignancies, eg, prostate cancer,[2] esophageal cancer,[3] bladder cancer,[1] and lung cancer.[4]
http://www.medscape.com/viewarticle/468905