1,1'-[methylenebis(oxy)]dibutane

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: read-across

Justification for type of information:

HYPOTHESIS FOR THE ANALOGUE APPROACH , SOURCE AND TARGET CHEMICAL(S), ANALOGUE APPROACH JUSTIFICATION and DATA MATRIX are provided in the attached document.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: OECD Joint meeting of the chemicals committee and the working party on chemical, pesticides and biotechnology, Guidance on grouping of chemicals, ENV/JM/MONO(2007)28

GLP compliance:

no

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Conc. based on:

test mat.

Validity criteria fulfilled:

yes

Conclusions:

Butylal predicted EC50(3h) is >100 mg/L.

Executive summary:

A read-across approach was developped to derive butylal EC10. The suggested source chemicals , i.e. dioxolane, was considered sufficient structurally, physicochemical and reactivity similar to the target chemicals, i.e. ethylal and butylal, to apply the read-across approach. A one-to-many read-across was performed since the endpoint information of one chemical, dioxolane, was used to estimate the activated sludge respiration inhibition test data for the target chemicals, i.e. ethylal and butylal, leading to the conclusion that their predicted EC50(3h) > 100 mg/L. This result is supported by the EC50 (3h) > 1000 mg/L found in OECD 209 and GLP test performed on 2,5,7,10-TETRAOXAUNDECANE (another acetal which is also considered sufficient structurally, physicochemical and reactivity similar to the target and source chemicals).

Description of key information

A read-across approach was developped to derive butylal EC10.

The suggested source chemicals , i.e. dioxolane, was considered sufficient structurally, physicochemical and reactivity similar to the target chemicals, i.e. ethylal and butylal, to apply the read-across approach. A one-to-many read-across was performed since the endpoint information of one chemical, dioxolane, was used to estimate the activated sludge respiration inhibition test data for the target chemicals, i.e. ethylal and butylal, leading to the conclusion that their predicted EC50(3h) > 100 mg/L. This result is supported by the EC50 (3h) > 1000 mg/L found in OECD 209 and GLP test performed on 2,5,7,10-TETRAOXAUNDECANE (another acetal which is also considered sufficient structurally, physicochemical and reactivity similar to the target and source chemicals).

Key value for chemical safety assessment

EC50 for microorganisms:

100 mg/L