Analyzing Pesticide Residue in Baby Food Using Atmospheric Pressure Ionization

The food industry is always seeking better ways to measure the presence of pesticides and other residues in baby food, which often face strict government regulations surrounding the levels that can be present.

On Monday, Simon Hird, a scientist at the Waters Corporation, presented findings from a study on the advantages of using atmospheric pressure ionization to analyze pesticide residues in baby food at the North American Chemical Residue Workshop (NACRW) in Fort Lauderdale, Florida.

Hird and his team used gas chromatography–tandem mass spectrometry (GC–MS/MS) to detect over 200 pesticides in baby food samples. They modified the widely used QuEChERS CEN Method 156624 by replacing the dispersive solid-phase extraction step with pass-through solid-phase extraction to remove fats, phospholipids, and pigments from the extracts of cottage pie baby food (1).

This method is suitable for the determination of GC-amenable pesticide residues in baby food, enabling compliance with the specific maximum residue levels set for food intended for infants and young children in Europe. Moreover, it provides a valuable tool for the food industry, allowing them to exercise due diligence and protect their brands.

“In baby food, in the European Union and the UK as well, we have specific regulations around baby food and infant formula,” Hird told LCGC in an interview. “We try to protect that population as much as possible.”

Because of the highly sensitive nature of GC–MS/MS, which incorporates atmospheric pressure ionization source (APGC) technology, the team was able to detect almost all the analytes at low concentrations of 0.00025 mg/kg (0.25 μg/kg), with a 1 μL injection volume.

The team used nitrogen gas for the separation, a cheaper and more accessible alternative to hydrogen. “Because of the ionization we can actually use nitrogen as an alternative, it's really cheap, really accessible,” Hird said. “You can switch very easily from hydrogen to nitrogen.”

Because of its ability to test low levels of pesticides, this method of investigation could also be used for environmental analysis, particularly in drinking water or soil, Hird added.

"It's not just a research exercise; this is something that can be really valuable in real laboratories in real life,” Hird said.

Reference

Hird, S. The Advantages of Using Atmospheric Pressure Ionization (APGC technology) for Determination of Pesticide Residues in Baby Foods using GC-MS/MS. Presented at: North American Chemical Residue Workshop 2023. July 22–25, 2023. Fort Lauderdale, Florida. O-01.