Zinc dimyristate

Hydrolysis

Description of key information

The assessment entity “C14-Ditetradecanoate” is the anion of a common saturated C14- fatty acid (tetradecanoic/myristic acid), present in e.g. bovine milk, butterfat as well as palm kernel and coconut oil. The endpoint is addressed with publicly available data on fatty acids with the same or a similar structure, including conservatively fatty acids with a shorter chain(i.e. C12) if relevant and appropriate in accordance with previously applied read-across approaches (U.S. EPA Fact Sheet, 2008). A registration dossier shall contain information on the environmental hazard assessment (Regulation 1907/2006, Article 10). For the environmental hazard assessment of myristic acid, the standard testing regime set out in Annexes VII and VIII is adapted in accordance with Section 1.2 and 1.3 of Annex XI so that “testing does not appear to be scientifically necessary” as follows: (I) The ecotoxic potential of the fatty acid (myristic acid) is assumed to be negligible. Fatty acids are generally not considered to represent a risk to the environment, which is reflected in their exemption from the obligation to register (Annex V, Section 9 and Regulation (EC) No 987/2008). (II)“Hydrolysis is not an important fate path in the environment due to the fact that fatty acids lack hydrolysable functional groups” OECD SIDS (2014) that are readily hydrolysed under environmental conditions (Health Canada, 2017). Fatty acids are hydrolytically stable in aqueous solutions in the pH range of 1-14 (U.S. EPA Fact Sheet, 2008, EFSA Journal, 2013). Since myristic acid does not contain hydrolysable functional groups, hydrolysis is not relevant for its fate of in the environment since it. (III) Myristic acid is expected to be biodegradable under aerobic conditions. In sum, hydrolysis does not appear to be a relevant degradation process of myristic acid in the environment.Taking into account thatmyristic acid is expected to be readily biodegradable under aerobic conditions, further tests withmyristic acid(C14- fatty acid) are not considered to be required.   References: OECD SIDS initial assessment profile- aliphatic acids (2014), CoCAM 6 September 30-October 3, Italy/ICCA, p. 41 Health Canada’s PMRA, Pest Management Regulatory Agency (2017). Ammonium Salt of Fatty Acid Proposed Registration Decision PRD2017-04, p. 36 U.S. Environmental Protection Agency, U.S. EPA (2008). Ammonium nonanoate (031802) Fact Sheet, OPP Chemical Code: 031802, p. 2 EFSA Journal (2013). Conclusion on the peer review of the pesticide risk assessment of the active substance Fatty acids C7 to C18 (approved under Regulation (EC) No 1107/2009 as Fatty acids C7 to C20), European Food Safety Authority, Parma, Italy, Vol 11(1):3023