New POPs in the water environment: distribution, bioaccumulation and treatment of perfluorinated compounds - a review paper

Perfluorinated compounds such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are emerging environmental pollutants. From the available literature, tap and surface water samples in several countries were found to be contaminated with PFOS and PFOA. These compounds were detected globally in the tissues of fish, bird and marine mammals, but their concentrations in animals from relatively more industrialized areas were greater than those from the less populated and remote locations. The bioconcentration factors (BCFs) of PFOS in fish were in the range of 10,000 or above, while the BCF of PFOA in fish was below 200. Blood samples of occupationally exposed people and the general population in various countries were found to contain PFOS and PFOA which suggested a possibility of atmospheric transport of these compounds. There is still a dearth of information about the environmental pathways of PFOS and PFOA. Some advanced oxidation methods, photocatalysis, adsorption, and reverse osmosis membrane filtration were found effective in degrading or removing PFOS and PFOA from the water environment. The presence of these compounds in the tap water, surface water and animal and human tissues indicates their global contamination and bioaccumulative phenomena in the ecosystems.