The ratio of the intensity of the quantification transition (Q) to the confirmation transition (q), Q/q, was used to confirm the peak identity of the samples. The identity of each peak was confirmed by comparing the experimental Q/q ratio of the sample with the theoretical Q/q ratio of the reference standard. Briefly, deviations were classified as ±20%
(relative intensity greater than 50%, Q/q ratio b2), ±25% (relative intensity of 20–50%, Q/q ratio 2–5), or ±30% (relative intensity of 10–20%, Q/q ratio N 10). These criteria are in accordance with the 2002/657/EC Decision [28].