Perfluorinated compounds (PFCs) are predominantly used in the textile industry for manufacturing breathable clothing and in the paper industry for producing dirt, grease and water repellent papers. Methods used: LC-MS, GC-MS, GC-FID, HPLC-UV/MS Furthermore the UV- and MS-responses of these model substances are studied under different conditions in order to evaluate possible approaches for semi-quantification. This method should also be easily transferable between different LC-MS/UV systems. Starting point is a method to separate and detect different substances which are already known to be present in food contact material and which comprise various chemical properties. The goal of this project is to develop an LC-MS method “as universally applicable as possible”. Quantification for the volatile compounds can be performed not only by GC-MS but also by GC-FID. ![]() But in most cases a standard substance is not available which would be needed for accurate quantification with LC-MS. A further challenge is the quantification of NIAS. Additionally: the ionization sources of different mass spectrometers do not produce the same mass spectra – this makes the transfer of methods to other devices difficult. Especially for LC-MS analysis there are various factors to pay attention to: different columns and different solvents for separation can be used, different ionization techniques are available – this all makes the identification challenging since different compounds need different settings. Signals are identified using MS-library matches (GC-MS) or accurate mass measurements and determination of the chemical formula followed by structure elucidation using MS/MS experiments and chemical structure databases. It has to keep in mind that it is almost impossible to identify all relevant NIAS in a sample.įollowing approach for the identification of NIAS is used: an extract of the respective material is prepared and analysed with GC-MS for volatile compounds and LC-MS for semi-volatile and non-volatile compounds. Since the physical and chemical properties of the NIAS present in a sample are often not known a combination of different analytical tools has to be used to detect most of those substances. In practice this means that there is a need to identify the non-intentionally added substances in a food contact material or a food sample and examine their migration potential and actual migration. ![]() Those substances should not exceed a migration rate of 10 µg/kg food (excluding substances that are carcinogenic, mutagenic or reprotoxic). According to article 3 of the Commission Regulation (EU) No 10/2011 a NIAS is defined as “an impurity in the substances used or a reaction intermediate formed during the production process or a decomposition or reaction product”. ![]() ![]() During the last years legislation and researchers focused more and more on “non-intentionally added substances” (NIAS) present in packaging materials. Additionally, the migration of substances present in the food contact materials into the food should not exceed unacceptable amounts. There are many requirements on these packaging materials for example physical protection of the groceries from temperature, compression and mechanical shock as well as barrier protection from oxygen, water vapor and dust or easy handling. During the last five decades the variety of food and beverage packaging increased with the development of numerous plastics materials and polymer modifications.
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