Conclusion

The approach taken in this ecological screening assessment was to examine various supporting information and develop conclusions based on multiple lines of evidence approach. Evidence that a substance is highly persistent and bioaccumulative together with evidence of potential for releases associated with commercial activity (including precursors) provides a significant indication of its potential to enter the environment under conditions that may have harmful long-term ecological effects. Substances that are persistent remain in the environment for a long time after being released, increasing the potential magnitude and duration of exposure. Substances (or their precursors) that have long half-lives in mobile media such as air and water, and partition into these media in significant proportions, have the potential to cause widespread contamination. Releases of small amounts of bioaccumulative substances (or related precursors) may lead to high internal concentrations in exposed organisms. Highly bioaccumulative and persistent substances are of special concern, since they may biomagnify in food webs, resulting in very high internal exposures, especially for top predators.

The presence of long-chain (C9-C20) PFCAs, their salts and their precursors results from anthropogenic activity. The long-chain (C9-C20) PFCAs and their salts are persistent.They have been found in remote regions, likely due to the long-range atmospheric or oceanic transport of volatile precursors and/or the acids themselves. Long-chain (C9-C20) PFCAs and their precursors have been detected in biota in Canada, including the Canadian Arctic. There is evidence that environmental concentrations are increasing with time for Canadian Arctic species such as polar bears, ringed seals, northern fulmars and thick-billed murres.There is empirical evidence that long-chain (C9-C20) PFCAs are bioaccumulative and can biomagnify in fish, some piscivorous birds, and mammals.

Based on the information presented in this draft screening assessment, it is proposed that long-chain (C9-C20) perfluorocarboxylic acids, their salts and their precursors are entering or may be entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity. While there is scientific evidence that long chain (C9-C20) PFCAs and their salts accumulate and biomagnify in terrestrial and marine mammals, only C11, C12 and C14 long chain PFCAs and their salts meet the numeric criteria for bioaccumulation as defined in the Persistence and Bioaccumulation Regulations.. Additionally, it is proposed that long chain PFCAs and their salts meet the criteria for persistence as set out in the Persistence and Bioaccumulation Regulations. It is, therefore, proposed that long-chain (C9-C20) perfluorocarboxylic acids, their salts, and their precursors meet one or more of the criteria in section 64 of CEPA 1999.