CONTEXT A detailed evaluation of the correlation and linearity of industrial hygiene retrospective exposure assessment (REA) for cumulative asbestos exposure with asbestos lung burden analysis (LBA) has not been previously performed, but both methods are utilized for case-control and cohort studies and other applications such as setting occupational exposure limits. OBJECTIVE (a) To correlate...

Health risks from asbestos exposures have been evaluated, considering past professional histories when exposures at workplaces were higher than today. A linear no-threshold (LNT) model has been applied, although its relevance is unproven. Fibers are often found in the lungs and pleura of deceased people. Fiber findings do not prove that a disease is caused by asbestos. It is reasonable to assum...

Asbestos causes pulmonary toxicity by mechanisms that in part involve reactive oxygen species (ROS). However, the precise source of ROS is unclear. We showed that asbestos induces alveolar epithelial cell (AEC) apoptosis by a mitochondrial-regulated death pathway. To determine whether mitochondrial-derived ROS are necessary for causing asbestos-induced AEC apoptosis, we utilized A549-rho(omicro...

From 1982 until 1991, a series of studies was performed to evaluate the airborne concentration of chrysotile asbestos associated with replacing gaskets and packing materials. These studies were conducted by the senior author in response to concerns raised by a report from the Navy in 1978 on asbestos exposures associated with gasket work. A series of studies was conducted because results of tho...

Iron in amphibole asbestos is implicated in the pathogenicity of inhaled fibers. Evidence includes the observation that iron chelators can suppress fiber-induced tissue damage. This is believed to occur via the diminished production of fiber-associated reactive oxygen species. The purpose of this study was to explore possible mechanisms for the reduction of fiber toxicity by iron chelator treat...

Although there have been a number of studies on the ingestion of asbestos, few studies exist on how the chrysotile asbestos itself is altered by the exposure to the acid stomach environment. This study has found that there are changes in the physical, chemical and surface properties of chrysotile asbestos as a result of exposure to water, strong acids, and simulated gastric juices. It was obser...

this study was performed during the abatement of two asbestos-containing materials (acm):baumlite board (cement flat board) and ceiling textile. the concentrations of total dust for personal sampling were 0.28 and 1.70 mg/m3 during baumlite board and ceiling textile abatements, respectively, when calculated with 8-hr time-weighted average (twa). the geometric mean (gm) asbestos concentrations w...

this study was performed during the abatement of two asbestos-containing materials (acm):baumlite board (cement flat board) and ceiling textile. the concentrations of total dust for personal sampling were 0.28 and 1.70 mg/m3 during baumlite board and ceiling textile abatements, respectively, when calculated with 8-hr time-weighted average (twa). the geometric mean (gm) asbestos concentrations w...

We studied asbestos, vitreous fiber (MMVF10), and refractory ceramic fiber (RCF1) from the Thermal Insulation Manufacturers' Association fiber repository regarding the following: free radical damage to plasmid DNA, iron release, ability to deplete glutathione (GSH), and activate redox-sensitive transcription factors in macrophages. Asbestos had much more free radical activity than any of the ma...