Distribution of Chlorinated Hydrocarbon Pesticides and PCBs in the ...

60 m column
conditions used were the same as those used for the 15 m
column with the following exceptions:
Oven Program:
Injection Mode:
initial temperature 100"~; hold
for-? min, then program at 10°C
mln to 300°C and hold 5 min.
Gr~b splitless injection carrier
splitting resumed after 1 min.
A baseline a-nd injection blank (e., solvent injected)
and calibration standard were run at the start of each daily use
of the gc.
b) ~ssignment Criteria of CG/ECD Chromatograms
A peak was assigned to a given chlorinated compound only
if all of the following criteria were satisfied:
e
i) The corrected retention time was within f0.02 minutes
of that expected.
ii) Upon co-injection with the authentic material, the
sample and standard compounds co-eluted as one peak.
iii) The compound was expected in the florisil column
fraction injected.
iv) The GC peak shape resembled that of the authentic
compound.
Quantitation
Response was measured by peak height (1986 samples, trips
one and two) or by peak areas (1987 samples and all biota
samples). All compound peaks were quantitated against the
internal standard, decachlorobiphenyl, using the formula,