Chloramphenicol (CAP), a broad-spectrum antibiotic, was detected in several herb and grass samples from different geographic origins. Due to its suspected carcinogenicity and linkages with the development of aplastic anemia in humans, CAP is banned for use in food-producing animals in the European Union (EU) and many other countries. However, products of animal origin originating from Asian countries entering the European market are still found noncompliant (containing CAP) on a regular basis, even when there is no history of chloramphenicol use in these countries. A possible explanation for the continued detection of these residues is the natural occurrence of CAP in plant material which is used as animal feed, with the consequent transfer of the substance to the animal tissues. Approximately 110 samples were analyzed using liquid chromatography coupled with mass spectrometric detection. In 26 samples, the presence of CAP was confirmed using the criteria for banned substances defined by the EU. Among other plant materials, samples of the Artemisia family retrieved from Mongolia and from Utah, USA, and a therapeutic herb mixture obtained from local stores in the Netherlands proved to contain CAP at levels ranging from 0.1 to 450 µg/kg. These findings may have a major impact in relation to international trade and safety to the consumer. The results of this study demonstrate that noncompliant findings in animal-derived food products may in part be due to the natural occurrence of chloramphenicol in plant material. This has implications for the application of current EU, USA, and other legislation and the interpretation of analytical results with respect to the consideration of CAP as a xenobiotic veterinary drug residue and the regulatory actions taken upon its detection in food.

In this study, a version of the "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method was modified to use ethyl acetate (EtOAc) rather than acetonitrile (MeCN) for extraction in the determination of multiple pesticide residues in fruits and vegetables. EtOAc is better suited than MeCN for gas chromatographic (GC) analysis with electron capture detection (ECD) and nitrogen-phosphorus detection (NPD). The method entailed extraction of 30 g chopped sample plus 5 g NaHCO(3) and 30 g anhydrous Na(2)SO(4) with 60 mL EtOAc using a probe blender. After a centrifugation step, removal of residual water and cleanup were performed using dispersive solid-phase extraction (dispersive-SPE) with MgSO(4) and primary secondary amine (PSA) sorbent. (14)C-labeled chlorpyrifos with liquid scintillation counting was used to assist in optimizing and characterizing the method, and GC-ECD and GC-NPD were used for analysis of 24 selected pesticides. The method was validated using tomato, apple and frozen green bean matrices spiked at 0.05, 0.5, and 5 mg/kg. For 22 of the analytes, recoveries averaged 93% for all three commodities over the validation range with a relative standard deviation of 10% (n = 1182). Lower recoveries of dichlorvos were obtained with the method and iprodione determination was compromised in the green beans by an interfering peak. Typical limits of detection were 0.005-0.01 mg/kg with the method.

This article gives an extensive overview of the wide range of analytical procedures developed for the detection of amphenicol antibiotic residues (chloramphenicol, thiamphenicol, and florfenicol) in many different types of foodstuffs (milk, meat, eggs, honey, seafood). Screening methods such as microbial inhibition methods, antibody-based immunoassays using conventional and biosensor-based detection systems, and some methods based on alternative recognition systems are described. The relative advantages and disadvantages of these methods are discussed and compared. The current status and future trends and developments in the need for accurate and rapid detection of this group of antimicrobials are also discussed.