Validation of evacuated canisters for sampling volatile organic compounds in healthcare settings
ABSTRACT Healthcare settings present a challenging environment for assessing low-level concentrations of specific volatile organic compounds (VOCs) in the presence of high background concentrations of alcohol from the use of hand sanitizers and surface disinfectants. The purposes of this laboratory-based project were to develop and validate a sampling and analysis methodology for quantifying low-level VOC concentrations as well as high-level alcohol concentrations found together in healthcare settings. Sampling was conducted using evacuated canisters lined with fused silica. Gas chromatography/mass spectrometry analysis was performed using preconcentration (for ppb levels) and loop injection (for ppm levels). For a select list of 14 VOCs, bias, precision, and accuracy of both the preconcentration and loop injection methods were evaluated, as was analyte stability in evacuated canisters over 30 days. Using the preconcentration (ppb-level) method, all validation criteria were met for 13 of the 14 target analytes-ethanol, acetone, methylene chloride, hexane, chloroform, benzene, methyl methacrylate, toluene, ethylbenzene, m,p-xylene, o-xylene, alpha-pinene, and limonene. Using the loop injection (ppm-level) method, all validation criteria were met for each analyte. At ppm levels, alpha-pinene and limonene remained stable over 21 days, while the rest of the analytes were stable for 30 days. All analytes remained stable over 30 days at ppb levels. This sampling and analysis approach is a viable (i.e., accurate and stable) methodology that will enable development of VOC profiles for mixed exposures experienced by healthcare workers.
SourceAvailable from: Ryan F Lebouf[Show abstract] [Hide abstract]
ABSTRACT: Objectives To identify and summarise volatile organic compound (VOC) exposure profiles of healthcare occupations. Methods Personal (n=143) and mobile area (n=207) evacuated canisters were collected and analysed by a gas chromatograph/mass spectrometer to assess exposures to 14 VOCs among 14 healthcare occupations in five hospitals. Participants were volunteers identified by their supervisors. Summary statistics were calculated by occupation. Principal component analysis (PCA) was used to reduce the 14 analyte inputs to five orthogonal factors and identify occupations that were associated with these factors. Linear regressions were used to assess the association between personal and mobile area samples. Results Exposure profiles differed among occupations; ethanol had the highest geometric mean (GM) among nursing assistants (similar to 4900 and similar to 1900 mu g/m(3), personal and area), and 2-propanol had the highest GM among medical equipment preparers (similar to 4600 and similar to 2000 mu g/m(3), personal and area). The highest total personal VOC exposures were among nursing assistants (similar to 9200 mu g/m(3)), licensed practical nurses (similar to 8700 mu g/m(3)) and medical equipment preparers (similar to 7900 mu g/m(3)). The influence of the PCA factors developed from personal exposure estimates varied by occupation, which enabled a comparative assessment of occupations. For example, factor 1, indicative of solvent use, was positively correlated with clinical laboratory and floor stripping/waxing occupations and tasks. Overall, a significant correlation was observed (r=0.88) between matched personal and mobile area samples, but varied considerably by analyte (r=0.23-0.64). Conclusions Healthcare workers are exposed to a variety of chemicals that vary with the activities and products used during activities. These VOC profiles are useful for estimating exposures for occupational hazard ranking for industrial hygienists as well as epidemiological studies.Occupational and Environmental Medicine 07/2014; 71(9). DOI:10.1136/oemed-2014-102080 · 3.23 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: We report the instrumentation of a μ-GC system that was capable of performing real-time analysis of sub-ppb-levels of organic mixture vapors. This system consists of a multi-stage preconcentrator/injector, a capillary column with at-column heater configuration and a photo ionization detector (PID). A tablet computer was embedded inside the instrument case to form a stand-alone system that can provide both instrument control and chromatogram data handling without an external computer. Through the compact design of fluidic system, this fully functional GC measured 30 (l) × 17(w) × 8(h) cm and the weight was less than 3 kg. This system could be powered by either a 12 V DC adapter or batteries. Mixtures of 10 organic compounds were tested to demonstrate the performance of this system. Separation of the 10 compounds took only 2 min due to the rapid temperature programming ability of at-column heater. The detection limit ranged from 0.02 to 0.36 ppb can be achieved with 1.0 L sample volume. The analytical cycle including sampling, separation and cooling required only 15 min. The stability of this μ-GC was evaluated by analyzing VOCs at ~ 3 ppb vapor concentration through continuous operation over 24 h. The retention time varied less than 1.2% (RSD, n = 120). The variation in peak areas ranged from 2.2% (benzene) to 5.2% (m-xylene).Microchemical Journal 05/2013; 108:161–167. DOI:10.1016/j.microc.2012.10.016 · 3.58 Impact Factor