Characterizing the Chemical Profile of Incidental Ultrafine Particles for Toxicity Assessment Using an Aerosol Concentrator

Abstract

Incidental ultrafine particles (UFPs) constitute a key pollutant in industrial workplaces. However, characterizing their chemical properties for exposure and toxicity assessments still remains a challenge. In this work, the performance of an aerosol concentrator (Versatile Aerosol Concentration Enrichment System, VACES) was assessed to simultaneously sample UFPs on filter substrates (for chemical analysis) and as liquid suspensions (for toxicity assessment), in a high UFP concentration scenario. An industrial case study was selected where metal-containing UFPs were emitted during thermal spraying of ceramic coatings. Results evidenced the comparability of the VACES system with online monitors in terms of UFP particle mass (for concentrations up to 95 µg UFP/m3) and between filters and liquid suspensions, in terms of particle composition (for concentrations up to 1000 µg/m3). This supports the applicability of this tool for UFP collection in view of chemical and toxicological characterization for incidental UFPs. In the industrial setting evaluated, results showed that the spraying temperature was a driver of fractionation of metals between UF (<0.2 µm) and fine (0.2–2.5 µm) particles. Potentially health hazardous metals (Ni, Cr) were enriched in UFPs and depleted in the fine particle fraction. Metals vaporized at high temperatures and concentrated in the UF fraction through nucleation processes. Results evidenced the need to understand incidental particle formation mechanisms due to their direct implications on particle composition and, thus, exposure. It is advisable that personal exposure and subsequent risk assessments in occupational settings should include dedicated metrics to monitor UFPs (especially, incidental).

In Vitro Toxicity of Industrially Relevant Engineered Nanoparticles in Human Alveolar Epithelial Cells: Air–Liquid Interface versus Submerged Cultures

“…In addition, nano-sized particles may be unintentionally released to workplace air during advanced, as well as traditional ceramics manufacturing processes such as machining, combustion/heating processes, thermal coating, etc. [5][6][7][8][9][10][11][12][13][14][15]. This has also been observed in other industrial sectors [16].…”

Atomic spectrometry update – a review of advances in environmental analysis

“…Two new air sampler designs of note were reported. The Versatile Aerosol Concentration Enrichment System (VACES) enabled 17 simultaneous sampling of ultrafine particles both on filters and in a liquid suspension for subsequent chemical and toxicity measurements. The Time Resolved Atmospheric Particle Sampler (TRAPS) coupled 18 a rotary cascade impactor to an OPC so that both coarse particles (1 μm) and fine particles (0.1 μm) could be monitored at high temporal resolution.…”

“…A procedure for preparing lter-based RMs for the measurement of both black carbon and brown carbon by optical techniques and for measuring OC and TC fractions by combustion techniques involved 22 a novel approach in which a commercially available inkjet printer was used to print ink containing organic and inorganic components onto lter media at programmable print densities. In order to address the lack of RMs for studies using the oxygen-isotope mass-independent fractionation signal, a useful metric for probing the pathways of atmospheric sulfates, puried O 3 was reacted 23 with sodium sulte to produce three 17 O-enriched sulfate candidate RMs that were analysed using a pyrolysis method calibrated using USGS RM 35 (nitrogen and oxygen isotopes in sodium nitrate).…”