Volatile organic compounds sampler

Each of these considerations must be resolved before a personal monitor can be applied to air pollution research and characterization studies. Some advances have been made for carbon monoxide, volatile organic compounds, acid aerosols, and particulate matter (PM-10 and RSP these represent the masses of all particles collected in samplers with 50% cut sizes of 10 and 25 xm, respectively) and its components (12, 22-31). Each advance is still undergoing development, and further advances can be anticipated for these as well as for other pollutants. The next generation of monitors will probably include devices for some pollutants that incorporate the use of microsensors. Currently, microsensors are being examined for detection of nitrogen dioxide and ozone, but the range of sensors available suggests that they can be used for a number of compounds (10, 32) ... 

The first representative reference values for indoor air in German households were derived from a study conducted by the old Federal Health Office into around 500 households in West Germany in 1985/86 (Krause, Chutsch and Henke, 1991). In 2007 updated reference values for individual volatile organic compounds (VOCs) and for aldehydes (Tables 9.3 and 9.4) were derived from long-term sampling in >550 households by means of diffusion samplers. Additionally a number of mostly regional studies have been made in schools (Heinzow et al., 1994), day-care centers (Schreiner, Wetzel and Kirchbach, 2001) and offices (Schlechter et al., 2004). 

Vroblesky, D.A. 2007. Passive diffusion samplers to monitor volatile organic compounds in groundwater. In R. Greenwood, G.A. Mills, and B. Vrana (eds), Passive Sampling Techniques in Environmental Monitoring, pp. 295-309. Amsterdam Elsevier. 

Pellizzari (1982) initiated the development and evaluation of trace levels of volatile organic compounds in industrial and chemical waste disposal sites. Ambient air samples were collected by a sampler equipped with Tenax GC adsorbent cartridges. Compounds were thermally removed from the adsorbent and analyzed by capillary GC/MS. The detection limit was at the pg/m level (Pellizzari 1982). 

Berg S. Jacobsson S. Nilsson B. 1980. Evaluation of an evacuated glass sampler for the analysis of volatile organic compounds in ambient air. J Chromatogr Sci 18 171-179. 

Cohen M.A., Ryan P.B., Yanagisawa Y. and Hammond S. (1990) The validation of a passive sampler for indoor and outdoor concentrations of volatile organic compounds. J. Air and Waste Management, 40, 993-997. 

Chung, C-W., M. T. Morandi, T. H. Stock M. Afshar, 1999. Evaluation of a passive sampler for volatile organic compounds at ppb concentrations, varying temperatures, and humidities with 24-hr exposures. 2. Sampler performance. Environ. Sci. Technol. 33 3666-3671. 

The risk of contamination must also be considered when a diffusive sampler is used to obtain air samples for determining volatile organic compounds. Thus, benzene, n-tetradecane. n-pentade-cane, n-hexadecane, n-heptadecane. and dioctyl phthalate [158], along with trichloromethane, 1.1,1-trichloroethane. trichloroethene, and tetrachloroethene [159] have all been detected in extracts from unexposed diffusive samplers. The measured concentrations varied from batch to batch, ranging from 0.005 pg to 0.14 pg per diffusive sampler in the case of the chlorinated hydrocarbons [159], and from 0.1 - 2.6 pg per diffusion collector for the aliphatic hydrocarbons and dioctyl phthalate [158]. 

A method was developed and tested for collecting semi- and non-volatile brominated organic compounds from air using a glass fiber filter and a high-volume air sampler. Exposed filters were extracted with acetone and the extracts analyzed by either glc/ms/comp, glc/ecd or tic. Recoveries of selected compounds from the filter material were >87%. 

Passive samplers are widely used in monitoring volatile organic chemicals (VOCs) in groundwater. Such samplers have the potential to reduce costs of monitoring from the high levels associated with the use of pumps to sample the test wells. Moreover, the risk of loss of volatile analytes during sample transport and storage is substantially reduced once the compounds are accumulated in the sampler sorption phase. 

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