Continual advances in the analysis of chemical residues in foods: Are methods finally good enough?

Steven Lehotay, Eastern Regional Research Center, USDA Agricultural Research Service, Wyndmoor, USA

Monitoring of pesticides, veterinary drugs, environmental pollutants, and other residues in a variety of food commodities are needed for a variety of purposes, including:

1) help ensure that agricultural, food safety, and environmental regulations are being followed; 2) check that products meet international food trade standards;

2) investigate antimicrobial resistance;

3) asses if organic food production practices are being followed when labeled as such;

4) provide survey data for risk assessment and assurances to consumers.

However, the cost and time needed for analysis places an incentive to develop and implement highly efficient and rapid methods that still meet monitoring needs. The fitness-for-purpose concept in analytical chemistry boils down to the question: Are the results good enough? Thus, the overarching goal of analytical chemists is to develop, validate, and implement the fastest, most cost-effective, and reliable methods that achieve “good enough” results.

The most efficient approach is to use the least resources (time, money, and labor) to analyze for as many contaminants at their concentrations of concern in as many sample types as possible. Due to many advantages, chromatography coupled with mass spectrometry has been the mainstay in chemical residue analysis for nearly 30 years, and commercial instruments have been continually getting faster, more sensitive, more selective (even with broader scope), albeit more expensive for the most powerful tools.

The limit of quantification (LOQ) needs for monitoring chemical residues has not changed much in the past 25 years, which has enabled much faster and easier sample preparation for high-throughput analysis followed by much less equivalent sample being introduced into the instruments to meet the needed LOQs.

The speaker will give an overview of the past, present, and future of efficient and effective methods to meet monitoring needs for chemical residues in food.