Potassium 1,1,2,2,3,3,4,4,4-nonafluorobutane-1-sulphonate

Endpoint summary

Additional information

Information on bioaccumulation of PFBS-K salt is provided by laboratory studies in the aquatic (fish), sediment (worm), and terrestrial (worm, plant species) compartments. In addition, studies are available of mammals and birds (see Toxicological information). Due to its high water solubility and low adsorption coefficient, the most likely route of exposure is by water. Bioconcentration factors measured for fish, as well as feeding studies on fish and a BSAF calculated for the sediment worm Lumbriculus variegatus, indicate little potential for PFBS-K salt to accumulate in aquatic organisms. Similarly, tests conducted on earthworms of Genus Eisenia showed little potential for PFBS-K salt to accumulate in terrestrial organisms. Studies of plants grown in intentionally-dosed soil or hydroponically in exposed medium showed little tendency for PFBS-K salt to accumulate in terrestrial plants.

A feeding study performed on dairy cows (elsewhere in this dossier) did not report a BMF, but showed that PFBS was eliminated rapidly during depuration in urine. In the chronic avian toxicity test, liver and serum samples were taken and analyzed to address potential bioaccumulation. Serum PFBS concentrations in males and females were approximately 6- to 13-fold less than those measured in diet, while liver PFBS concentrations were approximately 30-to 56-fold less than that in the diet. Additionally, a biomagnification study was done on pigs (elsewhere in this dossier). This study was deemed unreliable (Klimisch 3) for several reasons. While the BMF was slightly greater than one, no analysis of experimental error was provided. The authors did not measure depuration rate constants, but rather used several assumptions to model various rates and calculate a BMF. The steady state concentration and elimination half-life estimates used to calculate BMF were based on the rate constants which showed a broad confidence interval. It is felt that the reported BMF has enough potential for error associated with several aspects of its calculation that it can be considered to not be statistically significantly different from 1. Further, the actual values measured in each compartment were not available for review and there are no time-matched tissue and blood data. It is not possible to verify the BMF calculation given the information presented in the paper.

In addition to biomagnification studies, toxicokinetic data from higher mammals are available (elsewhere in this dossier). These include estimated serum elimination half-lives in rodents (~ 4 hours), non-human primates (~ 96 hours), and occupationally exposed workers (~ 26 days). Additional toxicokinetic studies of more limited reliability are also available. Taken together, these results indicate rapid elimination from terrestrial organisms.