sufficient to prevent degradation of benzenic aromates, naphthalene, phenols and petrol hydrocarbons ... was le to rest for 24 h at ambient temperature in order to allow .... heat inactivation or deep-freezing is impossible in the case of.
Environmental Science Processes & Impacts PAPER Stabilisation of groundwater samples for the quantification of organic trace pollutants† Cite this: Environ. Sci.: Processes Impacts, 2013, 15, 2329
Roland Becker,a Ute Dorgerloh,*a Hubert Theißenb and Irene Nehlsa The concentration of contaminants in groundwater samples can be decreased by degradation in the time course between field sampling and quantification in the laboratory, especially in samples from sites where degradation activity is enhanced by remediation measures. The sampling sites covered a variety of priority organic pollutants such as volatile aromatic and chlorinated compounds, phenols and petroleum hydrocarbons and different remediation strategies such as anaerobic and aerobic microbial in situ degradation, in situ chemical oxidation, and on-site purification with biological treatment. The stability of the contaminants' concentration was investigated over a time range of several hours without cooling in the autosampler of the analytical equipment (short term) and over several days of storage until analysis (long term). A number of stabilisation techniques suggested in international standards ISO 5667-3:2013 and ASTM D6517:2000 were compared both with regard to short term and long term stabilisation of the contaminants and their practicability for field sampling campaigns. Long term storage turned out to be problematic for most compound groups even under cooling. Short term stability was problematic also for volatiles such as benzenic aromates, naphthalene and volatile organic
Received 26th June 2013 Accepted 10th October 2013
halogenated compounds to be analysed by headspace gas chromatography. Acidification (pH
