Asbestos exposure during uncontrolled removal of sprayed-on asbestos

Asbestos-containing materials in place in buildings, especially sprayed-on asbestos, are still an important health threat. Clearance of these materials has to be operated by specifically trained workers wearing specific individual protection suits after containment of the contaminated area. Good work practices are, however, not always applied. We report the case of two workers hired for ∼1 week to remove sprayed-on amosite asbestos during the remodeling of a former industrial hall. Regulatory protective equipments were not used. A legal action was initiated after disclosure of the working conditions. Medical examinations were performed 18 and 22 months after exposure. Workers denied any other asbestos exposure. Lung function tests and chest computed tomography scans were normal. Very high levels of asbestos fibers and bodies were discovered on mineralogical analysis of bronchoalveolar lavage fluid (BALF) by phase contrast light microscopy and analytical electron microscopy. All fibers were amosite. An extrapolation considering duration of exposure, breathing pattern, and BALF fiber content suggests that the workers were exposed to airborne fiber concentrations in the range from several tens to about a hundred World Health Organization fibers per milliliter air. In conclusion, exposures to historical airborne fiber levels prevailing half a century ago may still occur today when the work regulations are not applied. In these conditions, even very short exposures may result in considerable lung fiber retention in case of amphibole exposure with the subsequent risk for developing asbestos-related diseases. Fiber analysis in BALF is useful to clarify such exposures.