SAL use DCM for the extraction and therefore whoever Lawrence is is
ill-informed re SAL practice. The extraction solvent used by labs has
been a matter of debate for some time. Others use hexane,
hexane:acetone, pentane etc. The problem is that the EA will not
stipulate a specific method. The use of DCM does mean that there is a
risk of extracting more polar analytes, such as humic acids but SAL use
a silica clean up to remove these before analysis.
regards
Marcus Wright
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