2-methoxyethyl methacrylate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read-across is based on the hypothesis that source and target substances have similar toxicological properties because
• they are manufactured from similar or identical precursors under similar conditions
• they share structural similarities with common functional groups: methacrylate esters
• the metabolism pathway leads to comparable products (methacrylic acid and short chain alcohol).

Therefore, read-across from the existing (eco)toxicity studies on the source substances is considered as an appropriate adaptation to the standard information requirements of REACH regulation

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
see cross reference “Justification for read-across”

3. ANALOGUE APPROACH JUSTIFICATION
see cross reference “Justification for read-across”

4. DATA MATRIX
see cross reference “Justification for read-across”

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

310 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: 95% c.i. 230-580 mg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

170 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: 95% c.i. 130-230 mg/L

Validity criteria fulfilled:

yes

Conclusions:

The 48 h EC50 in Daphnia magna was 170 mg/L (95% c.i. 130-230 mg/L).

Description of key information

48 h EC50=170 mg/L (95% c.i. 130-230 mg/L); OECD Guideline 202/ EU Method C.2; GLP; read-across from ETMA

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

170 mg/L

Additional information

No short-term toxicity data in freshwater invertebrates are available for MTMA. A short-term study in freshwater invertebrates is available for ETMA, which is considered reliable without restriction (Klimisch score 1). A justification for read-across is given in the endpoint summary "Aquatic toxicity".

The 48 h acute toxicity of ETMA to Daphnia magna was studied under static conditions according to OECD Guideline 202, adopted 4 April 1984 and EU Method C.2. Daphnids were exposed to control and test chemical at nominal concentration of 52.7, 79.0, 118.5, 177.8, 266.7, 400.0 mg/L for 48 h. Mortality/immobilisation was observed daily.

The 24 h EC50 based on measured initial concentrations was 310 mg/L (95% c.i. 230 – 580 mg/L); the 48 h EC50 based on measured initial concentrations was 170 mg/L (95% c.i. 130 – 230 mg/L).

LC50 values of 62.3 mg/L for MTMA and 30.97 mg/L for ETMA were predicted using ECOSAR V1.11. This supports the hypothesis, that effect levels in the same order of magnitude can be expected for the target and source substance. Thus, the result obtained with the source substance ETMA can be used as surrogate date for the target substance MTMA.