Identification and quantification of per- and polyfluorinated alkyl substances (PFAS) migrating from food contact materials (FCM).

Per- and polyfluorinated alkyl substances (PFAS) can be added to food contact materials (FCM) to increase their water and/or grease repellent properties. Some well-known PFAS are perfluoroalkyl carboxylic acids (PFCA), perfluoroalkyl sulfonic acids (PFSA), and polyfluorinated telomer alcohols (FTOH). Due to the strength of the carbon-fluorine bond, PFAS are chemically very stable and highly resistant to biological degradation, posing a risk to human health and the environment. To examine the presence of PFAS in paper-based FCM, various samples were collected, including popcorn bags, muffin cups, and pizza boxes with high total organic fluorine (TOF) content from the Danish and Spanish markets. The FCM composition was characterised by FTIR. Quantification of some well-known PFAS such as PFCA, PFSA, and FTOH was performed in food simulants using LC-MS/MS, and in addition a non-targeted screening approach was performed by LC-Orbitrap-HRMS. Among analysed samples, the highest concentrations of PFAS were found in a muffin cup made of cellulose (PFCA âˆ¼ 1.41 µg kg-1 food, FTOH âˆ¼ 11.5 µg kg-1 food), and the results were used to estimate dietary exposures to PFAS migrated from this FCM. Compared to measured TOF value in this sample, the fluorine from all quantified PFAS accounted for only 0.6%. Thus, a more powerful analytical approach was used to further investigate PFAS occurrence in this sample. Using non-targeted screening, an additional twenty compounds were identified, among them five with confidence level 1 and ten with confidence level 2. Many of them were either fluorotelomer carboxylic acids or sulfonic acids or ether-containing compounds.

Hypoglycin A in biological material: its detection and assay

A procedure for detection and measurement of Hypoglycin A in biological material is described, based on reaction of the amino acid with 1-dimethylaminonaphthalene-5-sulphonyl chloride (Dansyl chloride). The desired flourescent derivative can be separated from others by paper chromatography and measured by flourimetry after elution. Less than 0.2 microgram of hypoglycin A is detectable on chromatograms (AU)