[Determination of aerosol emission and bag filter efficiency in fire-proof products industries]

Today, the environmental pollution caused by fire-proof break producing factories is one of the critical and challenging issues in our country. Aerosols emission concentration of the factory stacks and determining of bag filters efficiency were aims of this study. In this research, the concentration of emitting dust from 6 stacks related to Kaolin preparation, Calcinatory, Shamout, Specific mass, Extrude Furnace and Shuttle Furnace units were measured during 2006-2008. Also, the efficiency of bag filters of Kaolin preparation, Calcinatory, Shamout, Specific mass units were determined in 2008. Devices M9096 Particulate Sampling Train and DURAG model [D-RC 80] were used in this research. The rates of dust concentrations in years 2006-9 in Kaolin unit were; 284, 112 and 12.5 mg/m3, in Shamout unit were; 120, 140 and 73 mg/m3, in Calcinatory were; 178, 179 and 173 mg/m3, Specific Mass were; 291, 283 and 60 mg/m3, in Shuttle Furnace were; 14.7, 14.3 and 14.8 and in Extrude Furnace were; 12.6, 13.7 and 12.7 mg/ m[3]. Efficiency of bag filters was 99.896% for Kaolin unit, 06.499% for Shamout unit, 92.348% for Calcinatory and 99.782% for Specific Mass unit. During 2006 and 2007 the rate of dust emission in Kaolin preparation, Calcinatory and specific mass have exceeded than the national emission standard but in 2008, the rate of dust emission from Kaolin Preparation and Specific Mass units were extensively reduced to the lower than national emission standard limit due to proper maintenance and replacing of damaged parts in time. Efficiency of bag filters has been ideal in Kaolin unit and Specific Mass unit but it was low in Shamout and Calcinatory units

Lucigenin chemiluminescence assay as an adjunctive tool for assessment of various stages of inflammation: a study of quiescent inflammatory cells.

A simple, fast, precise and biologically relevant toxicity assay for screening cytotoxicity of minerals would have distinct advantages due to its cost benefits and relative savings in time. Furthermore, a bioassay to differentiate acute and chronic in vivo pulmonary reactions could have potential value as predictors of fibrogenicity and pathogenicity. In this study we examined the potential use of lucigenin as a probe to evaluate the correlation between chemiluminescence (CL) generated by alveolar macrophages with the known cytotoxicity and patho genicity by conventional bioassays. In this study, we used small doses of dust (20 microg) to minimize cellular overload and to maintain homeostasis. Crystalline silica a highly fibrogenic dust was used as positive control and results are compared with those for bentonite, kaolin and talc. Among the three minerals compared with silica, bentonite was more reactive (27%) in CL assay and declined sharply compared to other minerals. This sudden decline in bentonite CL is caused by cytotoxicity leading to cell death. CL-induced by talc was comparable to silica and declines slowly. Kaolin on the other hand produced relatively a weaker (25%) CL compared to silica. Our data using relatively low doses of dust suggest that the CL assay may have a better predictive value in cytotoxicity evaluations compared to conventional toxicity assays.