Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Link to relevant study record(s)

Description of key information

The available evidence suggests that the substance is metabolised in the liver becoming bioavailable via the oral and dermal routes and also by inhalation if exposure occurs. The substance is expected to be mainly excreted in urine and has no potential to bioaccumulate.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential
Absorption rate - oral (%):
Absorption rate - dermal (%):
Absorption rate - inhalation (%):

Additional information

In accordance with the section 8.1.1 of Annex X of Regulation (EC) No 1907/2006 (REACH), the toxicokinetic profile of the substance (i.e. absorption, distribution, metabolism and elimination) was derived from the relevant available information collated in the dossier. The physical chemical characteristics, the results obtained from acute, repeated-dose, and reproductive toxicity studies on the substance, as well as information gained from genotoxicity assays were used to predict its toxicokinetic behaviour. The substance is used as a thickener, foam booster and emulsifier.


Structure and physical-chemical properties:

The target substance is a UVCB having a range molecular weight from 345 g/mol to 505 g/mol depending on the lenght of alkyl chain and the the number of ethylene oxide moieties (from 1 to 4). Its molecular structure is given below :

R-O-(CH2-CH2-O)n- CH2-C(=O)-NH- CH2- CH2-OH                (R = C13/15, n=1-2)

The alkyl chain (R) consists of either a C13 (about 70%) or a C15 chain (about 30%) which both can be linear (about 55%) but also branched (about 45%). The amount of condensed ethylene oxide moieties normaly varies between one and two but can also be up to four.

The substance is an active surface substance with a critical micelle concentration of 36 mg/L (log Kow not reliable). It has very low volatility based on its vapour pressure (7.65x10-10 Pa at 25°C). In the environmentally relevant pH range (pH4 to pH9), the substance is in the neutral form (i.e. no pH-dependency).




Oral/GI absorption:

The physical chemical characteristics described above suggest that the target substance is of adequate molecular size (< 500 g/mol) to participate in endogenous absorption mechanisms within the mammalian gastrointestinal tract. Being uncharged nature at physological pH values, the target substance is likely expected to cross gastrointestinal epithelial barriers. The absorption may be potentiated by the ability of the substance to dissolve into gastro-intestinal fluids and hence make contact with the mucosal surface.

These hypotheses are supported by oral systemic effects observed in the 90-day repeated dose toxicity study (OECD 408) and in the reproductive/developmental Toxicity Screening Test in the Han Wistar Rat test (OECD 421) performed on the substance in rats by gavage. In these studies, metabolic physiological adaptation to the substance in form of hepatocytes hypertrophy was noted, as well as inflammatory cell infiltration in the heart and myocardial fibres degeneration in male animals. These changes were concentration dependent and reversible within the 28-day recovery period.

The NOAEL was set to 300 ppm mg/kg bw/day in the 90-day repeated dose toxicity study. The observation of systemic effects indicates the oral bioavailability of the substance and/or its metabolites.

In light of these data, and the lack of specific information, the target substance was assumed to be 100% bioavailable by oral route for the DNELs calculation in the purpose of human health risk assessment.


Dermal absorption:

Based on its active surface properties, the uptake of the substance into the stratum corneum is enhanced considering its potential to solubilize lipids allowing the transfer between the stratum corneum and the epidermis. Furthermore, it is assumed that the dermal uptake of the substance in the blood is increased by its high water solubility. Finally, the substance is irritating to the skin which may upon high-dose contact favour dermal penetration of the substance. Nevertheless, no evidence of bioavailability via dermal route was observed in the acute dermal toxicity study up to 2000 mg/kg bw.

In light of these data, and the lack of specific information on the target substance, a dermal absorption of 100% was conservatively assumed for the DNELs calculation in the purpose of human health risk assessment.


Respiratory absorption:

The potential for inhalation toxicity was not evaluated in vivo.

The vapour pressure of the target substance (VP = 0.34 Pa at 25°C) indicated an absence of volatility and inhalability and therefore no exposure by inhalation is anticipated. Thus, at ambient temperature, no respiratory absorption is expected under normal use and handling of the substance.

Based on the result of the physico-chemical properties, toxicological properties and pattern of use, e.g. potential human exposure, it has been determined that inhalation is not anticipated to be a potential route of exposure during the normal use(s) of this material (cosmetics).

However, if inhalation occurs, the substance is expected to be directly absorbed across the respiratory tract epithelium by passive diffusion.

In light of these data, and the lack of specific information on respiratory absorption, the substance was conservatively assumed to be 100% bioavailable by inhalation for the DNEL calculation in the purposes of human health risk assessment.



Systemic distribution can be predicted from its physical chemical characteristics. Considering that the substance is active surface substance with highly water soluble, it is suggested that, upon systemic absorption by oral and dermal routes or by inhalation, the substance may be transported through the circulatory system in association with a carrier molecule. Afterwards, based on its character, the substance may cross cellular barriers without potential to accumulate into fatty tissues.



The results of the the 90-day repeated dose toxicity study (OECD 408) performed in the rat with the substance showed liver changes that are consistent with the increased metabolism associated with detoxification of a xenobiotic. This liver induction confirmed that a non-negligible part of the substance is metabolised following gastrointestinal tract absorption.



The substance, having a molecular weight lower than 500 g/mol, is expected to be mainly excreted in urine unchanged or as glucuronide and sulfate conjugates following oral exposure and inhalation. A minor amount (< 10%) may be excreted in bile as such or as metabolites following metabolism.

Any substance that is not absorbed from the gastro-intestinal tract, following oral ingestion, will be excreted in the faeces.

Following dermal exposure, as the substance, that have penetrated the stratum corneum is likely to be absorbed in the blood following excretion in urine unchanged or as glucuronide and sulfate conjugates if metabolisation in the liver occurs.