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Biodegradation screening studies for suitable read across substances indicate that Reaction mass of sodium hydrogen N-(1-oxooctadecyl)-L-glutamate and stearic acid is readily biodegradable according to OECD criteria (> 94% biodegradation in 28 and 21 days, respectively). Due to their ready biodegradability, hydrolysis is not expected to be a relevant degradation pathway for this substance. This assumption is based on the assumption that i) indirect photo transformation is negligible since the substance will not evaporate into the atmosphere based on its very low volatilization potential (vapour pressure < 0.00001 Pa) and ii) hydrolysis is negligible since most amides hydrolyze to acids extremely slowly under environmental conditions with half-lives measured in centuries. Electronegative groups on carbon or nitrogen greatly accelerate base catalyzed hydrolysis, but alkyl groups on nitrogen retard both acid and base catalyzed processes (Mabey and Mill, 1978).

Reaction mass of sodium hydrogen N-(1-oxooctadecyl)-L-glutamate and stearic acid is high water soluble (4.36 g/L) and has a low log Kow value (log Kow < -1.85) assuming a low adsorption potential. Thus, the substance will tend to be mainly distributed into the water phase if entering the environment. However, as the substance is considered to be readily biodegradable, persistence in this compartment is not expected.

Bioaccumulation in aquatic organisms is unlikely since Reaction mass of sodium hydrogen N-(1-oxooctadecyl)-L-glutamate and stearic acid has a very low log Kow of -1.85, which assume that the substance will not cross biological membranes. This assumption is supported by the complex structure and conformational flexibility of the substance, which indicate that passive diffusion through biological membranes is also sterically hindered.

In addition, if uptake by fish species occurs, extensive and fast biotransformation of the substance by amide hydrolases into glutamic acid and fatty acids is expected. Both glutamic acid and fatty acids will then be further used by these organisms as their main source of energy throughout all the different life stages (e.g., Juerss and Bastrop, 1995).  

Juerss K, Bastrop R. 1995. Chapter 7: Amino acid metabolism in fish. Biochem Mol Biol Fish 4: 159 -189

Mabey W & Mill T. 1978. Critical review of hydrolysis of organic compounds in water under environmental conditions.J Phys Chem Ref Data 7(2): 383-415