Sodium N-methyl-N-(1-oxo-9-octadecenyl)aminoacetate

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

The PBT Assessment for Reaction products of oleoyl sarcosine with sodium hydroxide is based on the criteria set out in the “Guidance on information requirements and chemical safety assessment, Chapter R.11: PBT Assessment” (ECHA, 2012).

Persistence

Reaction products of oleoyl sarcosine with sodium hydroxide is considered to be readily biodegradable based on one study according to OECD 301B performed with the structurally closely related category member (Z)-N-methyl-N-(1-oxo-9-octadecenyl) glycine (C18-acid, CAS 110-25-8) (85.2% (ThCO2) after 28 d). Thus, the test substance does not meet the screening criterion for persistency and it is not considered to be P or vP.

Bioaccumulation

No experimental data on bioaccumulation are available. The high log Kow of 6.62 - 7.64 (KOWWIN v1.68) as an intrinsic chemical property of the substance might indicate a potential for bioaccumulation since it is above the trigger value set out in Annex IX, column 2 of Regulation (EC) No 1907/2006. However, this value might over- or under-estimate the bioaccumulation potential since the environmental fate in regard to biodegradation and metabolism and excretion of the substance are not reflected by the log Kow itself. The gathered information from QSAR-estimation in combination with data on environmental behaviour and excretion provide enough evidence (in accordance to the Regulation (EC) No 1907/2006, Annex XI General rules for adaptation of the standard testing regime set out in Annexes VII to X, 1.2.), to cover the data requirements of Regulation (EC) No 1907/2006, Annex IX to state that the substance is likely to show low bioaccumulation potential.

Due to ready biodegradability and considerable potential of adsorption, the substance can be effectively removed in conventional sewage treatment plants (STPs) by biodegradation and by sorption to biomass (ECHA, 2012). If released into the aquatic environment, Reaction products of oleoyl sarcosine with sodium hydroxide undergoes extensive biodegradation and sorption on organic matter. Thus, the bioavailability of the substance to aquatic organisms in the water column is reduced rapidly. The relevant route of uptake of the substance in aquatic organisms is considered predominantly by ingestion of particle bound substance. 

Should the substance be taken up by fish it is not expected to be rapidly metabolized via enzymatic hydrolysis to the corresponding hydrolysis products. However, mammalian data (rats) available for one of the category members showed that after oral administration of [14C]Sodium N-lauroylsarcosinate (CAS 137-16-6), 82 - 89% was excreted after 24 h in the urine and faeces (CIR, 2001), clearly indicating the capacity of mammal depuration systems to rapidly eliminate the substance from the body. Moreover, frequent oral application to rats did not cause accumulation of radiolabelled [14C]Sodium N-lauroylsarcosinate (CAS 137-16-6) in bone and in muscle tissue (Allison, 1994). These two studies provide strong evidence of the expected low bioaccumulation potential of the Sarcosine category members. A validated (Q)SAR model (BCFBAF v3.01) resulted in BCF values of 335.4 - 1509 L/kg based on Arnot-Gobas model (upper trophic). This value is clearly below 2000 L/kg to be classified as bioaccumulative or very bioaccumulative (Annex XIII criterion for Bioaccumulative (B) substances, Regulation (EC) No 1907/2006)).

In conclusion, the log Kow of 6.62 - 7.64 overestimates the true potential for bioaccumulation. Only low concentrations are expected to be found in the aquatic environment. After uptake, fast excretion and direct elimination is expected based on mammalian data reducing the bioaccumulation potential. BCF/BAF values estimated with the BCFBAF v3.01 program also indicate that the substance will not be bioaccumulative (all well below 2000 L/kg (Annex XIII criterion for Bioaccumulative (B) substances, Regulation (EC) No 1907/2006)). Based on the above information, the substance does not meet the Bioaccumulative (B) or very Bioaccumulative (vB) criteria.

Toxicity

Available acute aquatic toxicity data are > 0.1 mg/L. Moreover, the test substance is readily biodegradable and not classified as carcinogenic (category 1 or 2), mutagenic (category 1 or 2), or toxic for reproduction (category 1, 2 or 3) according to Directive 67/548/EEC or carcinogenic (category 1A or 1B), germ cell mutagenic (category 1A or 1B), or toxic for reproduction (category 1A, 1B or 2) according to Regulation (EC) No 1272/2008. Additionally, there is no other evidence of chronic toxicity, as identified by the classifications T, R48 or Xn, R48 according to Directive 67/548/EEC or specific target organ toxicity after repeated exposure (STOT RE category 1 or 2) according to Regulation EC No 1272/2008. Thus, the screening criteria are not met and the substance is not considered to meet the T criterion.

Conclusion

In conclusion the substance is not considered to meet the criteria to be classified as PBT or vPvB based on the available data.