The safety evaluation of food contact materials requires excluding mutagenicity and genotoxicity in migrates. Testing the migrates using in vitro bioassays has been proposed to address this challenge. To be fit for that purpose, bioassays must be capable of detecting very low, safety relevant concentrations of DNA-damaging substances. There is currently no bioassay compatible with such qualifications. High-performance thin-layer chromatography (HPTLC), coupled with the planar SOS Umu-C (p-Umu-C) bioassay, was suggested as a promising rapid test (~6 h) to detect the presence of low levels of mutagens/genotoxins in complex mixtures. The current study aimed at incorporating metabolic activation in this assay and testing it with a set of standard mutagens (4-nitroquinoline-N-oxide, aflatoxin B1, mitomycin C, benzo(a)pyrene, N-ethyl nitrourea, 2-nitrofluorene, 7,12-dimethylbenzanthracene, 2-aminoanthracene and methyl methanesulfonate). An effective bioactivation protocol was developed. All tested mutagens could be detected at low concentrations (0.016 to 230 ng/band, according to substances). The calculated limits of biological detection were found to be up to 1400-fold lower than those obtained with the Ames assay. These limits are lower than the values calculated to ensure a negligeable carcinogenic risk of 10⁻⁵. They are all compatible with the threshold of toxicological concern for chemicals with alerts for mutagenicity (150 ng/person). They cannot be achieved by any other currently available test procedures. The p-Umu-C bioassay may become instrumental in the genotoxicity testing of complex mixtures such as food packaging, foods, and environmental samples.

Assessment of food authenticity from upstream in the supply chain is critical for the food industry. Environmental challenges and geo-political situations are causing shortages of raw materials resulting in a potential risk for food fraud. An example of this issue is the adulteration of edible oils by the addition of low-price oil, frying oil, or even non-edible grade oils mixtures threatening foods industries, consumer safety, and trust. Reliable screening tools to assess raw materials authenticity are therefore needed. Assessment of an improved alternative approach using high performance thin layer chromatography (HPTLC) is shown as a tool to evaluate edible oil authenticity and adulteration. Two methods were tested including an untargeted method based on fingerprints profiling for detection of adulteration with vegetable oil and a targeted method for mineral oil adulteration detection (e.g., paraffin wax). Statistical analysis was applied to determine acceptance criteria range to assess variability, limit of adulteration detection, and reproducibility. The robustness of the method was tested within an interlaboratory study using palm oil. Detection of adulteration with edible oils was achieved at levels from 5 to 25% while < 5% was predicted for mineral oils adulteration. Both methods showed promising results in terms of adulteration detection capability making this approach a reliable, and efficient tool to assess and monitor edible oils quality with added value in the field.