Raina et al. [47] have developed a LC–MS/MS method for determination
of 24 OPPs and their degradation products in air samples,
using electrospray ionization in the positive mode (ESI+). They
reported that APCI ionization mode gave poorer sensitivity for
these molecules than ESI+. Formost compounds two characteristics
transitions with best sensibility for each compound were selected,
choosing the most intense for quantitative analysis (SRM1) and the
second transition (SRM2), along with the ratio SRM1/SRM2 for confirmation
of the compound. The method detection limits ranging
typically from0.2 to 10 pgm−3 with typical air volumes of 2700m3.