In some areas, such as parts of California, Virginia and New Jersey (and across the globe in Turkey and Corsica), asbestos-bearing rock is close enough to the surface that construction and other human activities can disturb it, leading to release of high concentrations of asbestos fibers into the air and dust (ATSDR 2001a; Hasanoglu et al. 2003; Luo et al. 2003).