Emerging pollutants in the Maltese environment : perfluoroalkyl substances as organic pollutants in Maltese coastal waters

Abstract

This dissertation study was carried out around the analysis of PFAS outfall into the coastal seawater of the Maltese islands. The site selected for sampling and analysis was Hofra z-Zghira which is situated on the southern coast of mainland Malta and was deemed to be a suitable sampling site due to its vicinity to the Delimara power station. Samples were taken from the surface and subsurface waters of the sampling area and such samples were treated with Waters Oasis® HLB 6cc extraction cartridge by carrying out solid phase extraction. After treatment the samples were analysed using a Waters® ACQUITY UPLC® analysis system coupled with a TQ-D Detector which made use of UPLC-MS/MS parameters. Through this, the MRM spectra generated were able to be used for semiquantitative determination of PFAS concentration within all the samples tested. The prevailing results had shown that significant concentrations of three specific PFAS were detected reliably using this method, and such were PFHxA, PFHpA and PFBuS. Across the samples analysed, a statistical analysis was carried out in order to determine whether or not there was any significant difference in concentration of these PFAS both in an overall manner and in terms of distance from the shoreline. The statistical analysis had then shown that the difference was not significant enough to warrant the acceptance of the proposed hypothesis. All in all, it was determined that with concentrations seemingly on the rise, further study into PFAS outfall in the Maltese coastline is warranted based on these results.