Chemical airborne vapors from man-made sources constitute potential human health hazards, as well as having adverse effects on the Environment as a whole.
More and more attention is now being given to monitoring levels of volatile chemicals from PPM down to sub-PPB levels, as chronic exposure even at low levels may lead to a number of different health conditions, including cancer.
Volatile and Semi-volatile chemicals both in our outdoor and indoor air must be considered in determining overall human exposure. Measurement of these chemicals in air is usually performed by Gas Chromatography / Mass Spectrometry to quantify concentration levels of individual compounds to determine the overall exposure risks.
Usually, levels are too low for direct GCMS detection, requiring sample enrichment or pre-concentration for detection down to PPB (parts per billion) and sub-PPB levels. “Whole Air” field collection of air samples into inert canisters continues to be the Gold Standard for obtaining accurate air monitoring results, using evacuated containers which are opened in the field to collect the air sample, followed by laboratory analysis under reliable and controlled conditions.
Alternative approaches using thermal desorption tubes modify the sample in the field, exposing the collected chemicals to a more reactive environment which often results in inconsistent recovery during thermal desorption in the laboratory.
Entech is the world leader in providing canister monitoring technology based on US EPA Methods TO-14A and TO-15. Virtually hundreds of volatile and semi-volatile compounds can be recovered using this approach, making canisters the most universal technique for measuring virtually every GC compatible airborne compound of interest. Entech places a proprietary ceramic called Silonite™ on the inside of sampling canisters to make them extremely inert, allowing the recovery of more compounds than any other air sampling device.