Ethoxyquin

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Peer-reviewed assessment report (attached in section 13)

Qualifier:

according to guideline

Guideline:

other: OECD II A 8.3.1

GLP compliance:

yes

Test organisms (species):

Daphnia magna

Test type:

flow-through

Total exposure duration:

48 h

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 2.9 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

2 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality

Conclusions:

The study was conducted according to OECD II A 8.3.1 FIRRA 72-2(a) on ethoxyquin (CAS 91-53-2) itself. The study is specified in a draft assessment report and can be considered scientifically reasonable with no deficiencies in documentation or deviations from the guidelines. Hence, the validity criteria were met and the results can be considered as reliable to assess the toxicity of the test item towards daphnia magna.
Short term toxicity to aquatic invertebrates was tested in a flow-through test design, the 48-hour EC50 value for daphnia magna exposed to ethoxyquin was 2 mg ethoxyquin/L based on mortality.

Executive summary:

The Daphnia magna 48 hour EC50 for ethoxyquin technical was determined in flow-through conditions to be > 2.0 mg/L. The 95 % confidence limits were 1.7 and 2.9 mg/L. The no mortality/immobility concentration and NOEC were 1.0 mg ethoxyquin/L.

Description of key information

Short-term toxicity to invertebrates: EC50 (48 h) = 2.0 mg/L for daphnia magna (OECD II A 8.3.1, flow-through)

Short-term toxicity to invertebrates: EC50 (24 h) > 2.9 mg/L for daphnia magna (OECD II A 8.3.1, flow-through)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2 mg/L

Additional information

There is a valid, peer-reviewed OECD II A 8.3.1 guideline study without relevant deviations on ethoxyquin itself available, assessed with Klimisch 2. In this study, the following EC50 values were determined: 2.0 mg/L (48 h) and > 2.9 mg/L (24 h). The results can be considered as sufficiently reliable to assess the toxicity of ethoxyquin to daphnids.

Based on the obtained results, the test item does not need to be classified as acute hazardous to the aquatic environment according to the Regulation (EC) No. 1272/2008.