Reaction mass of stearoyl sarcosine and palmitoyl sarcosine

Endpoint summary

Additional information

One study for aquatic invertebrates is available for Reaction mass of N-(1-oxooctadecyl)sarcosine and N-hexadecanoyl-N-methylglycine (EC 947-850-7). Read-across to the structurally related source substances Reaction products of oleoyl sarcosine with sodium hydroxide and N-methyl-N-(C18-(unsaturated)alkanoyl)glycine (EC 701-177-3) were conducted for short-term toxicity to fish. N-methyl-N-(C18-(unsaturated)alkanoyl)glycine (EC 701-177-3) was used as source substance for long-term toxicity to aquatic invertebrates, toxicity to aquatic algae and toxicity to microorganisms. This read-across approach was applied in order to fulfil the standard information requirements according to Annex IX of Regulation (EC) No 1907/2006 and is in compliance with Annex XI, 1.5, of Regulation (EC) No 1907/2006.

The physico/chemical properties of the target and source substances are similar due to the structural similarities, i.e., sarcosine head group and the hydrocarbon tail. In addition, due to the pKa of the target substance (pKa = 3.96, major constituent), at physiological pH values (above 6) the target substance is expected to be in the anionic form, as are the source substances. As a result, the chemistry of the target and source substances, in solution (above pH 6), are expected to be similar. The sodium cation (Na+) found in one source substance is not expected to create much difference in properties, particularly for solution behavior, such as Log Kow and water solubility. In aqueous solution, these cations are dissociated from the molecule.

Thus, the selected source substances are considered suitable representatives for the assessment of the aquatic toxicity of the target substance. A detailed read-across justification in provided in IUCLID section 13.

The short-term toxicity to freshwater fish was assessed for Reaction products of oleoyl sarcosine with sodium hydroxide and N-methyl-N-(C18-(unsaturated)alkanoyl)glycine (EC 701-177-3). Both studies were carried out according to OECD guideline 203 and GLP. The lowest reported effect concentration is a LC50 (96 h) of 0.37 mg/L (nominal).

The short-term toxicity to aquatic invertebrates was determined in a study with the target substance Reaction mass of N-(1-oxooctadecyl)sarcosine and N-hexadecanoyl-N-methylglycine (EC 947-850-7). The study was carried out according to OECD guideline 202 and GLP resulting in an EC50 (48h) of 15.93 µg/L (meas. TWA).

The long-term toxicity to aquatic invertebrates was assessed for N-methyl-N-(C18-(unsaturated)alkanoyl)glycine (EC 701-177-3). The study was carried out according to OECD guideline 211 and GLP. The NOEC (21d) was determined to be ≥ 183 µg/L (meas. TWA).

The toxicity to aquatic algae conducted with the source substance N-methyl-N-(C18-(unsaturated)alkanoyl)glycine (EC 701-177-3) was tested in two studies according to OECD 201 resulting in an ErC50 (72 h) 6.3 mg/L (measured initial) and a NOErC (72 h) of 0.91 mg/L (measured).

The toxicity to microorganisms was assessed in two studies according to OECD 209 for the source substance N-methyl-N-(C18-(unsaturated)alkanoyl)glycine (EC 701-177-3) with activated sludge as inoculum. Effects on the respiration of activated sludge microorganisms was recorded resulting in an EC50 (3 h) of > 100 mg/L and a NOEC (3 h) of 10 mg/L (nominal).

Based on the available results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5), which is characterized by a comparable structure and chemistry, it can be concluded that the target substance Reaction mass of N-(1-oxooctadecyl)sarcosine and N-hexadecanoyl-N-methylglycine (EC 947-850-7) will exhibit comparable effects on aquatic organisms.