Those who develop ailments from asbestos are almost always those who are exposed everyday in a work setting. Incidence of illness increases with increasing exposure. After prolonged exposure, it may take that person 10-40 years to develop illness. Short-term exposure or low concentration exposure are unlikely to cause disease, whereas long-term exposure or high concentrations is likely to cause ailments.
Exposure to long and thin fibers is the most damaging exposure type due to the fibers ability to reach the lower airways and alveolar regions of the lung, to be retained in the lung longer, and to be more toxic than short and wide fibers or particles. Wide particles deposit in the upper respiratory tract and do not to reach the lung and pleura, where asbestos has damaging effects.