The frequency of cases of accelerated silicosis associated with exposure to dust from processing artificial stones is rapidly increasing globally. Artificial stones are increasingly popular materials, commonly used to fabricate kitchen and bathroom worktops. Artificial stones can contain very high levels of crystalline silica, hence cutting and polishing them without adequate exposure controls represents a significant health risk. The aim of this research was to determine any differences in the emission profiles of dust generated from artificial and natural stones when cutting and polishing. For artificial stones containing resins, the nature of the volatile organic compounds (VOCs) emitted during processing was also investigated. A selection of stones (two natural, two artificial containing resin, and one artificial sintered) were cut and polished inside a large dust tunnel to characterize the emissions produced. The inhalable, thoracic, and respirable mass concentrations of emissions were measured gravimetrically and the amount of crystalline silica in different size fractions was determined by X-ray diffraction. Emissions were viewed using scanning electron microscopy and the particle size distribution was measured using a wide range aerosol spectrometer. VOCs emitted when cutting resin-artificial stones were also sampled. The mass of dust emitted when cutting stones was higher than that emitted when polishing. For each process, the mass of dust generated was similar whether the stone was artificial or natural. The percentage of crystalline silica in bulk stone is likely to be a reasonable, or conservative, estimate of that in stone dust generated by cutting or polishing. Larger particles were produced when cutting compared with when polishing. For each process, normalized particle size distributions were similar whether the stone was artificial or natural. VOCs were released when cutting resin-artificial stones. The higher the level of silica in the bulk material, the higher the level of silica in any dust emissions produced when processing the stone. When working with new stones containing higher levels of silica, existing control measures may need to be adapted and improved in order to achieve adequate control.

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ObjectivesThe United States National Institute for Occupational Safety and Health (NIOSH) is developing a protocol to assess the containment performance of closed system transfer devices (CSTDs) when used for drug preparation (task 1) and administration (task 2) and published a draft protocol in September 2016. Nine possible surrogates were proposed by NIOSH for use in the testing. The objectives of this study were to: (A) select the most appropriate surrogate; (B) validate the NIOSH protocol using this surrogate; and (C) determine the containment performance of four commercial CSTDs as compared with an open system of needle and syringe using the validated NIOSH protocol.Methods2-Phenoxyethanol (2-POE) was selected as a surrogate based on its water solubility, Henry’s volatility constant, detectability by mass spectrometry, and non-toxicity. Standard analytical validation methods including system suitability, limit of detection (LOD), and limit of quantitation (LOQ) as well as system cleaning validation were performed. The amount of 2-POE released when the CSTDs were manipulated according to two tasks defined by NIOSH was determined using mass spectrometry coupled to thermal desorption and gas chromatography. This approach allows sensitivity of detection below 1 part per billion (ppb). Equashield, Tevadaptor (OnGuard), PhaSeal, and ChemoClave were assessed according to manufacturers’ instructions for use.Results2-POE was tested and validated for suitability of use within the NIOSH protocol. A simple and efficient cleaning protocol achieved consistently low background values, with an average value, based on 85 measurements, of 0.12 ppb with a 95% confidence interval (CI) of ±0.16 ppb. This gives an LOD for the tests of 0.35 ppb and an LOQ of 0.88 ppb. The Equashield, Tevadaptor (OnGuard), and PhaSeal devices all showed average releases, based on 10 measurements from five tests, that were less than the LOQ (i.e. < 0.88 ppb), while the ChemoClave Vial Shield with Spinning Spiros showed average releases of 2.9±2.3 ppb and 7.5±17.9 ppb for NIOSH tasks 1 and 2 respectively at the 95% confidence level. The open system of needle and syringe showed releases, based on two measurements from a single test, of 4.2±2.2 ppb and 5.1±1.7 ppb for NIOSH tasks 1 and 2 respectively at the 95% confidence level.Conclusions2-POE proved to be an ideal surrogate for testing of CSTDs using the NIOSH protocol. We propose that a CSTD can be qualified using the NIOSH testing approach if the experimental LOQ is less than 1 ppb and the release values are below the LOQ. Equashield, Tevadaptor (OnGuard), and PhaSeal meet these acceptance criteria and can therefore all be qualified as CSTDs, but the ChemoClave system does not and so would not qualify as a CSTD.

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Diacetyl is a potentially harmful chemical that is used as an artificial flavouring in the food industry and may also be generated during processing of some natural products including coffee. In Europe, an 8-h time weighted average occupational exposure limit (TWA-OEL) of 20 ppb has been adopted for diacetyl, together with a short-term exposure limit (STEL) of 100 ppb. A new measurement method involving sampling on thermal desorption tubes and analysis by gas chromatography–mass spectrometry has been used to investigate potential exposure to diacetyl, and the related compound 2,3-pentanedione, at eight companies involved in the coffee industry including large- and small-scale manufacturers and coffee shops. A total of 124 static and personal samples were collected. In the majority of personal samples airborne concentrations of diacetyl were <5 ppb, with those at coffee shops generally <1 ppb. However, diacetyl concentrations in ~40% of the long-term personal samples, mainly originating from one site, were found to be in excess of the newly adopted European TWA-OEL of 20 ppb. Diacetyl concentrations up to 400 ppb were detected on the static samples, with the highest values occurring during grinding of roasted coffee beans. 2,3-Pentanedione was also detected in most of the samples at airborne concentrations around half of those for diacetyl. A significant number of other volatile organic compounds (VOCs) were also detected at sub-ppm concentrations, including acetoin, aliphatic carboxylic acids, aldehydes, ketones and esters, methylfuran, furfural and furfuryl-based alcohols and ketones, and nitrogen containing compounds, such as pyridines and pyrazines. In laboratory tests, diacetyl emissions generated during heating of whole beans were found to be significantly lower than those from heating the same beans after grinding. Diacetyl emissions from both ground and whole beans were also found to be significantly dependent on temperature.