Perfluorinated chemicals have been widely used in commerce for the last few decades

Introduction Perfluorinated chemicals have been widely used in commerce for the last few decades. Until recently little was known about their environmental fate and even less was known about their potential environmental effects. Since Giesy and co-workers first demonstrated the widespread occurrence of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in wildlife there has been interest in determining the biological and possible ecological effects of these compounds. The assessment of possible effects of these chemicals has been hampered by a limited understanding of their mode of action. While certain of the chemicals are known to be peroxisome proliferators, the most abundant compound PFOS is not a classic or complete peroxisome proliferator. Here we summarize recent toxicological and mode of action studies available for perfluorinated compounds (PFCs) and use this information and environmental concentration data to determine the degree of environmental risk these compounds pose.