ASK ELi: Asbestos Danger?

Image: asbestos fibers

Editor’s note: ELi recently reported on a MIOSHA investigation of complaints about asbestos exposure at the East Lansing Wastewater Treatment Plant. As we reported, one complaint alleged that asbestos "is on all piping in the plant and mainly on the first floor in the tunnels. . . . It has been falling down on the floor, walked on, and dry swept up by employees who are not trained on asbestos and do not know the hazards.” In response, readers have asked us the following type of question, and we in turn asked Dr. Ken Rosenman, Chief of the Division of Occupational and Environmental Medicine and Professor of Medicine at MSU’s College of Human Medicine, to answer for our readers. Note that we did not ask specifically about East Lansing’s wastewater treatment plant, but rather asked more generally about the type of asbestos exposure described in the allegation made to MIOSHA.

The question: "How dangerous would it be for workers to sweep up loose asbestos and walk through steam tunnels where asbestos dust was falling, all without respirators or masks?”

Dr. Rosenman answers:

The risk of asbestos exposure is based on how much and how long you are exposed to asbestos and whether or not you smoke cigarettes. Certainly sweeping up asbestos or disturbing asbestos insulation off of pipes on a daily basis for 20 to 30 years would increase one's risk of developing lung scarring, lung cancer, cancer of the lining of the lung, vocal cord cancer and colon cancer. The highest risk would be for lung cancer, particularly if one smoked cigarettes as there is a strong interaction (synergism) between asbestos and cigarettes. The risk goes up to 60 times for asbestos-exposed workers who continue to smoke versus 4-8 times among individuals with asbestos or cigarettes alone.

Walking through the tunnels with asbestos containing pipes whose insulation is breaking down will probably not increase a person's risk for asbestos-related disease in a measurable way. Similarly, intermittent sweeping over a few years will probably not increase a person's risk for asbestos related disease in a measurable way. 

There is no acute toxic effect from asbestos. [Editor’s note: This means that if you’re exposed to asbestos, you won’t suddenly become very ill.] People who have adverse effects from asbestos, typically have the effects more than 20 years after the initial exposure. Evaluation of a chest radiograph by a specialist in asbestos disease more than 20 years after initial exposure for the presence of scarring of the lining of the lung is one way to assess whether a previous asbestos exposure may have been sufficient to increase the risk of cancer.  

There are medical screening tests for colon cancer for those over 50 (colonoscopy) and CT scan of the chest for lung cancer for individuals who have had daily, repeated (15 or more ) years of cigarette or asbestos exposure.    

ELi is grateful to Dr. Rosenman for his assistance with this week’s “Ask ELi” column. Remember, if you have an issue you want ELi to investigate, contact us!