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The VOC Solvents Emissions Directive was the main policy instrument for the reduction of industrial emissions of volatile organic compounds (VOCs) in the European Union. It covers a wide range of solvent-using activities, e.g. printing, surface cleaning, vehicle coating, dry cleaning and manufacture of footwear and pharmaceutical products.
Breath gas analysis is a method for gaining information on the clinical state of an individual by monitoring volatile organic compounds (VOCs) present in the exhaled breath. Exhaled breath is naturally produced by the human body through expiration and therefore can be collected in non-invasively and in an unlimited way. [1]
IMS chip at the U.S. Pacific Northwest National Laboratory: this dime-sized chip provides dozens of channels through which ions travel (perpendicular to plane of view) to be separated and identified Ion mobility spectrometry ( IMS ) It is a method of conducting analytical research that separates and identifies ionized molecules present in the ...
For the analysis of volatile compounds, a purge and trap (P&T) concentrator system may be used to introduce samples. The target analytes are extracted by mixing the sample with water and purge with inert gas (e.g. Nitrogen gas) into an airtight chamber, this is known as purging or sparging.
The profiling of VOCs emitted by living organisms takes an increasing importance in various scientific domains like in medicine, in food sciences or in chemical ecology. For instance, in medicine, non-invasive diagnosis techniques of cancer based on the profiling of VOCs from the exhaled breath have been developed.
They are nitrates produced in the thermal equilibrium between organic peroxy radicals by the gas-phase oxidation of a variety of volatile organic compounds (VOCs), or by aldehydes and other oxygenated VOCs oxidizing in the presence of NO 2. [1] [2] [3]
In a photoionization detector, high-energy photons, typically in the vacuum ultraviolet (VUV) range, break molecules into positively charged ions. [2] As compounds enter the detector they are bombarded by high-energy UV photons and are ionized when they absorb the UV light, resulting in ejection of electrons and the formation of positively charged ions.
Indoor materials such as gypsum boards or carpet act as VOC 'sinks', by trapping VOC vapors for extended periods of time, and releasing them by outgassing. The VOCs can also undergo transformation at the surface through interaction with ozone. [42] In both cases, these delayed emissions can result in chronic and low-level exposures to VOCs. [50]