Determination of perfluoroalkyl acids in different tissues of graminaceous plants

A method for the determination of 12 perfluoroalkylacids (PFAA) in vegetal samples was proposed. The analytical procedure was developed to optimize the detention of short-chain PFAA (C<8) due to their higher potential to be translocated and bioaccumulated in plants than long-chain congeners. The method, based on ultrasonic extraction, clean-up and HPLC-MS/MS analysis, determined PFAA in the different plant tissues allowing to study the PFAA distribution and partition in vegetal compartments. The performance of this analytical procedure was validated by analysing samples (root, stem and leaf) of reed grass. The validated method was then applied to graminaceous plants from an agricultural area impacted by a fluorochemical plant discharge (Northern Italy). The PFAA congeners were detected in the most of samples with PFAA concentrations in whole plant ranging from < LOD to 10.4 ng g-1 ww and with a greater rate of PFAA accumulation in corn cob than corn kernel. The proposed approach is particularly relevant in edible plant investigation because PFAA levels recorded in the comestible fractions provide information for human risk assessment due to vegetable consumption. Furthermore data on the remaining not edible parts, intended for breeding forage, are also useful for the assessment of the PFAA transfer in the breeding trophic chain.