Perfluamine

Short-term toxicity to fish

Description of key information

Perfluorotripropyl amines (PTPA) is not expected to be toxic to fish at the limit of solubility (5.96 µg/L) by readacross from category members.  When other category members were tested, no toxicity was observed to fish in tests conducted with nominal concentrations ranging from 100 to 2700 mg/L .  This categorical result  is considered applicable to PTPA.

Additional information

Perfluorotripropyl amines (PTPA) is a member of the Perfluorinated Organic Chemicals, C5-C18 category. Because these substances exhibit similarity in their physicochemical properties and toxicological properties in mammals, and because available data indicates that parent molecules are not reactive toward biological molecules and cannot undergo bioactivation by normal enzymatic processes, they can be considered members of a chemical category. Data gaps for ecological toxicity can therefore be addressed by read-across and/or trend analysis between category members. Short-term toxicity of PTPA to fish has not been studied. However, two reliable studies are available for other category members. Perfluoro-N-C1,3-alkyl morpholines (FC-770) was tested using D. rerio. After 96-hours, no toxicity was observed from a water-soluble fraction prepared at 100 mg/L. The mean measured concentration during the test was 0.096 mg/L. Perfluoro-C6,8-furans, pyrans and acyclic ethers (FC-77) was tested using P. promelas. In this case, test chambers were prepared at an initial loading rate of 1000 mg/L. Exposure concentrations were not measured, however, the test material could not be entirely dissolved and was observed in the test chambers throughout the experiment. No toxicity was observed. Other category members had study reports which were less detailed but were suitable for weight of evidence in the aggregate. These category members were not toxic to fish in limit tests with nominal concentrations ranging from 750 to 2700 mg/L. The analytically determined concentrations for FC-770 is are not reasonable to use for readacross since FC-770 solubility is substantially higher than that of PTPA. Lack of toxicity at the limit of solubility is read across qualitatively to PTPA. The solubility of PTPA was determined to be 5.96 µg/L in organism-free Daphnia medium controls during the short-term toxicity test. This value is greater than the measured PTPA solubility in water (0.381 µg/L) but less than the analytically determined concentrations in medium containing live daphnids. The organism-free medium solubility value is understood to be better representative of PTPA solubility in natural waters, and avoids potential impacts on the analytical result by the action of living organisms. Therefore, 5.96 µg/L is accepted as the basis for estimating the highest possible exposure concentration of PTPA in order to define the LC50.

Please see IUCLID section 13 for the category justification and a matrix of aquatic toxicity data for members of the Perfluorinated Organic Chemicals C5-C18 category.