Although targeted analysis is highly valuable to assess compliance
with safety and regulatory standards, it is applied with the
premise that the chemical is likely to be present and the purpose
of analysis is thus to quantify the target chemical or chemicals. A
growing number of routine analyticalmethods aremulti-residue in
nature, giving the potential to detect and quantify larger numbers
of compounds using non-selective clean-up with increased chromatographic
separation and selective (usuallyMS-based) detection
[26,27]. Techniques such asmultidimensional gas chromatography
(GC×GC) [28,29] can separate very large numbers of compounds
by the use of orthogonal stationary phases. The logical extension
to these approaches is the application of rapid spectroscopic
techniques in exploratory modes, such as time-of-flight MS [30],
to identify chemical residues in food. Such approaches are commonly
operated together with effect-based (e.g., in vitro) assays.
The assays may be online (in parallel or tandem) or offline and
such approaches could change the primary food safety question
of ‘how much?’ to ‘what is present?’ This is a very different question
to answer and will require significant advances in exposure
assessment and risk characterisation.