2-(2-(2-ethoxyethoxy)ethoxy)ethanol

Endpoint summary

Description of key information

ORAL - RATS (mg/kg): 10600

DERMAL LD50 (mg/kg)

TEGME read across substance: Rabbit: 7.45mg/kg

TEGBE read across substance: Rabbit: 3.45ml/kg

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

10 610 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Additional information

In an old but reliable acute oral toxicity study, male albino rats were administered single doses of 2-(2-(2-ethoxyethoxy)ethoxy)ethanol by gavage. The LD50 was calculated at 10.61g/kg. In a poisoning case, a young child self administered a huge dose estimated in excess of 25g/kg of a formulated brake fluid based on triethylene glycol ethers. Whilst intensive medical support was briefly required, the patient made a full recovery

There is however measured data for two substances either side of it in the homologous series of these triethylene glycol ethers. A full and detailed justification for a category approach for meeting the individual data requirements for glycol ethers is included as an attachment in chapter 13 to this dossier. For this specific end point, Chapter 13 of the IUCLID dossier submitted by the lead registrant contains a full and detailed justification for using a category approach to fulfil the data requirements for glycol ethers and to specifically justify the use of read across for certain end points, including this one. The analysis included in this document shows there is a clear trend towards reducing toxicity vertically down a homologous series. Interpolation between the results of other glycol ethers within the same homologous family of triethylene glycol ethers can be considered a valid approach to meeting the data requirements of this substance and sufficient to conclude that there is no hazard from this substance by this route up to the limit dose exposure of 2000g/kgbw. Data for the two analogue substances is shown below:

In an acute dermal toxicity study in rabbits under occluded conditions with the substance 2 -(2 -(2 -methoxyethoxy)ethoxy)ethanol in which key basic details were reported, an LD50 of 7100mg/kg was obtain. In an acute dermal toxicity study under occluded conditions using the substance 2 -(2 -(2 -butoxyethoxy)ethoxy)ethanol in rabbits, in which only basic details were reported, an LD50 of 3540mg/kg was obtain. It is reasonable to conclude that the acute LD50 by the dermal route for the substance 2 -(2 -(2 -ethoxyethoxy)ethoxy)ethanol will fall somewhere between these two values.

No acute toxicity data is available by the inhalation route but the extremely low volatility of this substance and low acute toxicity by other routes leads to the conclusion that such data is not required to conclude that there is no acute toxicity hazard by the inhalation route.

Justification for classification or non-classification

The available data indicates that this substance is of very low acute toxicity by all routes of exposure and classification is not warranted.