Analytical strategies for determination of chlorinated paraffins in foods: an up-to-date review

Chlorinated paraffins (CPs) are an extremely complex mixture composed of various carbon and chlorine homologues and contain thousands of constitutional isomers. Both short- and medium-chain chlorinated paraffins are persistent environmental contaminants and can be found ubiquitously in the environment and in food. Many methods have been reported for quantification of the total concentration of these mixtures. However, the comparability of test results amongst different laboratories is still challenging. In addition, the transformation products of CPs, chlorinated olefins, also interfere with the analysis and can lead to the overestimation of CPs content. This paper reviews different aspects of methods for analysing CPs in food, including availability of standards, sample pre-treatment, extraction, clean-up, detection, and quantification. Besides, the method performance for dietary exposure assessment is also touched upon. Moreover, feasible future directions are identified based on the current knowledge and existing literature.