2-(2-butoxyethoxy)ethyl acetate

Endpoint summary

Description of key information

Acute oral toxicity (LD50): rat=11920mg/kg, 7.1ml/kg, guinea pig=2340mg/kg, 2.7ml/kg.  mouse=6.6ml/kg, rabbit=2.8ml/kg, chicken=5.0ml/kg.

Acute inhalation (LC50).  Cannot be reached at saturated vapour concentration.

Acute dermal toxicity (LD50) rabbit=5400-5700mg/kg.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 340 mg/kg bw

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

5 400 mg/kg bw

Additional information

In a single dose acute oral toxicity study, male Wistar albino rats were exposed to 2 -(2 -butoxyethoxy)ethyl acetate. The LD50 value established was 11920mg/kg. In a single dose acute oral toxicity study, male and female guinea pigs were exposed to 2 -(2 -butoxyethoxy)ethyl acetate (DEGBEA). The LD50 established was 2340mg/kg. In an old acute toxicity study where only basic details were reported, oral acute LD50's were established for a number of species as follows: rat 7.1ml/kg , rabbit 2.8ml/kg, mouse 6.6ml/kg, guinea pig 2.7ml/kg, chicken 5.0ml/kg.

No data is available for the acute inhalation toxicity of this substance. A weight of evidence approach can be used using data from surrogate substances to predict both local and systemic effects from inhalation exposure. In an acute inhalation toxicity study in rats where basic study details were reported, the LC50 of 2 -butoxyethyl acetate (a read across substance for 2 -(2 -butoxyethoxy)ethyl acetate - EGBEA - for local effects) could not be established due to the low volatility of the substance. Exposure to the saturated vapour concentration (quantified as approximately 400ppm) for 4 hours produced no adverse response. In another acute inhalation study, rats were exposed to an atmosphere saturated with vapors of the substance 2 -(2 -butoxyethoxy)ethanol (DEGBE) for a period of 2 hours. This substance is a good surrogate for systemic effects due to the rapid in vivo hydrolysis of DEGBEA to DEGBE. No signs of mortality or adverse clinical signs apart from evidence for some eye irritation were observed, the latter probably due to aerosol exposure.

In an old acute dermal toxicity study, 2 -(2 -butoxyethoxy)ethyl acetate was found to have an LD50 of around 5.5 -5.8ml/kg in rabbits. This study did not meet the full requirements of current OECD guideline (not all end points reported), but the method was reported in some detail and the results therefore considered reliable. This figure is consistent with the acute oral toxicity data.

Justification for classification or non-classification

Based on the results for acute toxicity by the oral route (guinea pig data as worst case assumption), this this substance would not be classified for acute toxicity in accordance with the current EU guidelines. It should also be noted that, in any case, the guinea pig data is not normally used for acute toxicity classification (normally rat or mouse). However, the test substance would also not warrant classification for acute toxicity in both these two species. From the limited hazard data available, there appears to be no hazard from the inhalation of 2 -(2 -butoxyethoxy) ethyl acetate, not least because of its very low volatility. Classification criteria are clearly not met. The data for dermal acute toxicity in rabbits does not meet the classification criteria.