The use of pesticides in fruit and vegetable production is a common practice to prevent pest infestations and extend the shelf life of fresh produce. However, the presence of pesticide residues in food has raised concerns about potential health risks for consumers. To address these concerns, regulators set maximum residue levels (MRLs) for pesticides, which define the maximum amount of a pesticide that can be present in a given crop.
In a recently published article, Kari Ogantini of Waters Corporation and colleagues discuss the combined analysis of pesticide residues using mass spectrometry (MS) with gas chromatography (GC) and liquid chromatography (LC) . They explain that using Quick, Easy, Cheap, Efficient, Rugged, and Safe (QuEChERS) sample extraction and cleanup improves analytical efficiency for multiresidue analyses. In addition, ultrahigh pressure liquid chromatography (UHPLC) coupled with tandem quadrupole mass spectrometry (MS/MS) has been widely used for multiresidue pesticide analysis.
A challenge in enforcing MRLs is that in the EU, where pesticides are not explicitly mentioned in legislation, default MRLs are used for enforcement. This default value is set equal to the achievable limit of quantitation (LOQ) of the analytical method used for the analysis. National authorities control and enforce MRLs by testing samples for pesticide residue levels using analytical monitoring procedures. These programs check for compliance with MRLs, assess dietary exposures, and check for use of unauthorized pesticides. The food industry also conducts its own due diligence analysis to ensure compliance with the MRL.
Recent advances in GC-MS/MS utilizing atmospheric pressure ionization (APGC) have shown significant improvements in the performance of challenging pesticides in terms of selectivity, specificity, and speed of analysis compared to electron bombardment (EI). The combined use of mass spectrometry and chromatography has enabled the development of a single method for the analysis of liquid and solid samples.
While MRLs are in place to ensure the safety of our food supply, consumers must be aware of the potential risks associated with consuming foods that have been treated with pesticides. Choosing to buy organic produce grown without synthetic pesticides is one way to reduce your exposure to pesticide residues. In addition, washing and thoroughly cooking fruits and vegetables can also help reduce pesticide residues. The authors of the article emphasize that the use of advanced analytical techniques is important to ensuring the safety of our food supply and enabling regulators to effectively enforce MRLs.
Organtini, K.; Cleland, G.; McCall, E.; Hird, S. LC-MS/MS and GC-MS/MS analysis of fruit and vegetable extracts on a single quadrupole mass spectrometer Pesticide residues in food. Labmates online. https://www.labmate-online.com/article/laboratory-products/3/fritsch-gmbh/extracting-active-ingredients-from-cannabis-plants/2228 (accessed 12 April 2023)