Health and Saftey Aspects of Fiber Glass, 1998 Nonwovens Conference Proceedings

Fiber glass (FG) has been used for insulation, filtration, and reinforcements for more than 60 years. Because FG can release respirable fibers during manufacture and handling, respiratory health in the FG workplace has been the focus of numerous studies. Ongoing epidemiology studies of fiber glass workers find no consistent evidence of a causal relationship between human health effects and fiber glass exposure. However, in 1987, IARC designated fiber glass a “possible carcinogen” based on limited evidence from animal studies and inadequate evidence from human epidemiology. In 1988, the IPCS suggested that FGs pose “little, if any, health risk to humans.” In the 1990’s, a series of rodent inhalation studies demonstrated a broad range of biological reactivity for the different FGs-after lifetime exposure to very high doses, insulation FGs caused only transient irritation but two durable special application glass microfibers were pathogenic. Rodent studies also demonstrated a broad range of lung clearance rates for FGs-90% clearance required l0-120 days for insulation wools and 240-365 days for durable glass microfibers, compared to ~1000 days for asbestos. In the rodent studies, FGs and other SVFs with rapid lung clearance rates were not pathogenic; thus, new fiber-screening tests based on biopersistence may facilitate the identification of durable fiber types and their re-formulation into compositions that will not persist in the lung.