4-methylstyrene

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

The substance falls within the applicability domain of the selected (Q)SAR method.

Qualifier:

according to guideline

Guideline:

other: EPISUITE ECOSAR v 1.0 and 1.11

Principles of method if other than guideline:

QSAR

GLP compliance:

no

Test organisms (species):

Daphnia magna

Total exposure duration:

21 d

Remarks on exposure duration:

Chronic QSAR

Key result

Duration:

21 d

Dose descriptor:

other: ChV

Effect conc.:

0.451 mg/L

Nominal / measured:

not specified

Conc. based on:

act. ingr.

Basis for effect:

other: QSAR

Remarks on result:

other: D. magna

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.32 mg/L

Nominal / measured:

not specified

Conc. based on:

act. ingr.

Basis for effect:

other: QSAR

Remarks on result:

other: D. magna

Key result

Duration:

21 d

Dose descriptor:

other: ChV

Effect conc.:

0.098 mg/L

Nominal / measured:

not specified

Conc. based on:

act. ingr.

Basis for effect:

other: QSAR

Remarks on result:

other: Mysid shrimp

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.07 mg/L

Nominal / measured:

not specified

Conc. based on:

act. ingr.

Basis for effect:

other: QSAR

Remarks on result:

other: Mysid shrimp

Details on results:

The estimated toxicity to D magna using the EPA ECOSAR model was 0.451 mg/L (ChV). According to ECHA REACH Guidance R.10, if in the test report only the ChV is presented, the ChV can be divided by √2 to derive a NOEC. 0.451 mg/L was divided by root 2 to give a NOEC value of 0.32 mg/L. The same type of model was run for Mysid salt water shrimp. Obtained by modelling ChV value was 0.098, which gives the NOEC of 0.07 mg/L.

Validity criteria fulfilled:

not applicable

Conclusions:

Under the study conditions, 21 d NOEC for D. magna and Mysid shrimp were estimated to be 0.32 and 0.07 mg/L, respectively.

Executive summary:

A study was conducted to determine the 21 d chronic toxicity of the test substance to aquatic invertebrates using the EPI SUITE ECOSAR v 1.0 and 1.11 model. The estimated ChV (chronic value) in D. magna was 0.451 mg/L. The ChV corresponds to the geometric mean of the NOEC and LOEC. Thus, according to ECHA REACH Guidance R.10, the ChV can be divided by √2 to derive a NOEC. In this case 0.451 mg/L was divided by root 2 to give a NOEC value of 0.32 mg/L. The same type of model was run for Mysid saltwater shrimp. The obtained ChV value was 0.098, which gives a NOEC of 0.07 mg/L. Under the study conditions, 21 d NOEC for D. magna and Mysid shrimp were estimated to be 0.32 and 0.07 mg/L, respectively (US EPA, 2017).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.32 mg/L

Marine water invertebrates

Marine water invertebrates

Effect concentration:

0.07 mg/L

Additional information

A study was conducted to determine the 21 d chronic toxicity of the test substance to aquatic invertebrates using the EPI SUITE ECOSAR v 1.0 and 1.11 model. The estimated ChV (chronic value) in D. magna was 0.451 mg/L. The ChV corresponds to the geometric mean of the NOEC and LOEC. Thus, according to ECHA REACH Guidance R.10, the ChV can be divided by √2 to derive a NOEC. In this case 0.451 mg/L was divided by root 2 to give a NOEC value of 0.32 mg/L. The same type of model was run for Mysid saltwater shrimp. The obtained ChV value was 0.098, which gives a NOEC of 0.07 mg/L. Under the study conditions, 21 d NOEC for D. magna and Mysid shrimp were estimated to be 0.32 and 0.07 mg/L, respectively (US EPA, 2017).