2-ethylhexyl 3-mercaptopropionate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Pretreatment of the test substance: dilution in tap water used for ther fish-test whilst shaking on a shaking machine for 24h followed by separation of the water-insoluble part from the water soluble part of the test substance via filtration through paper filters previously rinsed with deionised water.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: zebrafish
- Source: Aquafarm Ryba, Zeven

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

96 h

Nominal and measured concentrations:

Screening test: 10, 1, 0.1 mg/L
1st main test: 10, 8, 4, 2, 1 mg/L
2nd main test: 1, 0.8, 0.4, 0.2, 0.1 mg/L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

1.03 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

Screening test

Concentration of Test Substance	Number of dead fish [%]
	24 h	48 h	72 h	96 h
10	100	100	100	100
1	0	0	0	0
0.1	0	0	0	0

 

1° Main test (Static Test Procedure):

Concentration of Test Substance	Number of dead fish [%]
	24 h	48 h	72 h	96 h
Control	0	0	0	0
10	100	100	100	100
8	100	100	100	100
4	100	100	100	100
2	100	100	100	100
1	86	86	86	86

 

2" Main test (Definitive Test, Semi-Static Test Procedure):

Concentration of Test Substance	Number of dead fish [%]
	24 h	48 h	72 h	96 h
Control	0	0	0	0
1.0	29	29	29	43
0.8	14	14	14	14
0.4	0	0	0	0
0.2	0	0	0	0
0.1	0	0	0	0

 

 

Executive summary:

The test substance was tested under semi-static conditions for toxicity towards fish according to OECD-Test Guideline 203. For this purpose the animals were exposed to different concentrations of the test substance. Under the conditions used for this study the LCso-value after 96h was caiculated to be 1.03 mg of test substance per litre.

Description of key information

LC50 = 1.03 mg/L (nominal)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

1.03 mg/L

Additional information

EHMP was tested under semi-static conditions for toxicity towards fish according to OECD-Test Guideline 203. For this purpose the animals were exposed to different concentrations of the test substance. Under the conditions used for this study the LC50-value after 96 h was caiculated to be 1.03 mg of test substance per litre.

 

Nominal values represent the real environmental conditions because the test substance is rapidly oxidized by the oxygen content in the aqueous phase. As the transformation products are less toxic than the parent substances (no free –SH groups) regulatory endpoints calculated on the basis of nominal concentrations represent a realistic worst case approach.