A Multi-Cyclone Sampling Array for the Collection of Size-Segregated Occupational Aerosols

Abstract

In this study a serial multi-cyclone sampling array capable of simultaneously sampling particles of multiple size fractions, from an occupational environment, for use in in vivo and in vitro toxicity studies and physical/chemical characterization, was developed and tested. This method is an improvement over current methods used to size-segregate occupational aerosols for characterization, due to its simplicity and its ability to collect sufficient masses of nano- and ultrafine sized particles for analysis. This method was evaluated in a chamber providing a uniform atmosphere of dust concentrations using crystalline silica particles. The multi-cyclone sampling array was used to segregate crystalline silica particles into four size fractions, from a chamber concentration of 10 mg/m(3). The size distributions of the particles collected at each stage were confirmed, in the air, before and after each cyclone stage. Once collected, the particle size distribution of each size fraction was measured using light scattering techniques to further confirm the size distributions. As a final confirmation, scanning electron microscopy was used to collect images of each size fraction. The results presented here, using multiple measurement techniques, show that this multi-cyclone system was able to successfully collect distinct size-segregated particles at sufficient masses to perform toxicological evaluations and physical/chemical characterization.

Differential activation of RAW 264.7 macrophages by size-segregated crystalline silica

“…The MCSA was described in detail previously [23] and particle size ranges are named for consistency with that publication and do not match other established naming conventions found in the literature. Briefly, the MCSA incorporates cyclones in a series of three successive stages.…”

“…One difficulty in completing size-dependent toxicity studies with CS is the difficulty in separating the occupational aerosol into distinct size ranges and in necessary quantities for toxicological studies. Recently our group published research on a novel multi-cyclone sampling array which enables the separation of occupational aerosols into distinct size ranges and in quantities needed for toxicological research [23]. …”

A Computer-Controlled SEM-EDX Routine for Characterizing Respirable Coal Mine Dust

“…While these alarming trends have not been fully explained, a number of causal factors have been suggested (e.g., see [14][15][16][17][18][19][20][21][22][23]), including exposure conditions and specific dust characteristics. , and includes all reported categories of CWP (i.e., severity categories 1, 2, and 3, and progressive massive fibrosis (PMF)).…”

“…In this case, individuals may be exposed to relatively high or variable dust concentrations and a range of dust characteristics [5,8,22]. Further, advances in mining equipment have yielded more powerful cutting machines for production activities, which are likely to generate relatively smaller dust particle sizes; and it has been suggested that small particles can be more harmful to health than larger respirable dust particles [21]. Indeed, particle size as well as shape (e.g., elongation, angularity, roughness) can affect the degree of dust particle deposition in the lungs [24].…”

A Low-Cost Device for Bulk Sampling of Airborne Particulate Matter: Evaluation of an Ionic Charging Device

“…Bulk sampling of aerosol (sampling airborne particles of all sizes) is commonly used for identifying the physical properties, chemical composition and toxicity of PM in both indoor and outdoor environments (Brauer et al, 1991;Camuffo et al, 1999;Lioy et al, 2002;Gysels et al, 2004;Says and Warheit, 2009;Mischler et al, 2013). To collect sufficient mass of particles for the types of analyses described above, either a long sampling duration or high flow rate is required.…”