Current issues involving screening and identification of chemical contaminants in foods by mass spectrometry

•Invited contribution to Special Issue on qualitative analysis by mass spectrometry.•Update of TrAC critical review in 2008 on MS identification of residues in food.•Critical review of the pertinent literature since 2008 on MS of food contaminants.•Integrates qualitative aspects of ambient MS, flow-injection MS, HRMS, hybrid MS.•Reviews and suggests criteria for MS method validation and identification.

Although quantitative analytical methods must be empirically validated prior to their use in a variety of applications, including regulatory monitoring of chemical adulterants in foods, validation of qualitative method performance for the analytes and matrices of interest is frequently ignored, or general guidelines are assumed to be true for specific situations. Just as in the case of quantitative method validation, acceptable method performance criteria should be established for qualitative analysis purposes to suit the analytical needs for given applications, and empirical method validation should be conducted to demonstrate the qualitative performance capabilities the method. This critical review article is intended to describe and discuss recent developments with of respect to qualitative aspects in mass spectrometry, and to make recommendations for validation of qualitative methods that meet common needs for monitoring of chemical contaminants in foods.