Nevertheless, peaks A-C for OIL2 and Oil 8 were identified using One of the replicate 50 ng on column injections produced peaks that were around four times higher than the other two replicates, gave lighter values for all three peaks and was most variable for peak A, which may relate to linearity. OIL2 was analysed twice with injections of 50 and 100 ng on column. Whilst there was an order of magnitude difference in peak amplitude the  13 C values for peaks B and C were reasonably consistent whilst the smallest peak A varied by around 3.6 ‰ (Figure ).