N-ethyl-N-(3-methylphenyl)propionamide

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 July 1996 to 24 July 1996

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

N-ethyl-N-(3-methylphenyl)propionamide

EC Number:

423-640-6

EC Name:

N-ethyl-N-(3-methylphenyl)propionamide

Cas Number:

179911-08-1

Molecular formula:

C12H17NO

IUPAC Name:

N-ethyl-N-(3-methylphenyl)propanamide

Test material form:

liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

0 hour fresh, 24 hour aged, 24 hour fresh, 48 hour aged;

Test solutions

Vehicle:

no

Details on test solutions:

At 0 hours a 1000 mg/l stock was prepared y dispersing 0.503g S032 into 500 ml Elendt M7 medium using high shear mixing for approximately 20 minutes at 16000 rpm. Test media were prepared by adding known volumes of stock to 500 ml Elendt Medium. A fresh stock was prepared 24 hours and used to prepare the hardness (as mg/l CaCO3) of selected test media were measured at 0, 24 and 48 hours using the appropriate methods. Temperature was measured daily.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
Daphnia magna (Crustacea : Cladocera) is a planktonic, filter-feeding invertebrate, widely distributed in the freshwaters of temperate regions around the world. It is widely considered to be sensitive to changes in water quality.

Daphnia magna were cultured in the laboratory according tothe procedures described in Ecotoxicology SOP 019. Cultures were maintained in a synthetic medium with the same chemical composition and similar pH and dissolved oxygen concentration as that used to prepare test solutions. Cultures were maintained in 800 ml of Elendt M7 medium. The cultures were fed daily with cells of the green algae Chlorella vulgaris. Cultures were reset using 10 neonates, when they became gravid their numbers were reduced from 10 to 5. Neonates produced by adults were removed daily.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

248 mg/l as CaCO3

Test temperature:

19°C

pH:

7.9

Dissolved oxygen:

8.1 mg/l

Nominal and measured concentrations:

Nominal: 0, 32, 56, 100, 180 and 320 mg/l
Measured (geometric mean of measured): 0, 25, 47, 91, 150 and 290 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 6mm bore glass tube
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per vehicle control (replicates): 4

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light / 8 hours dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mobility

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

ca. 25 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 75 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 48 hours EC50 of the test item based on the geometric mean of measured concentrations and calculated by the probit method is 75 mg/l

Executive summary:

The acute toxicity of Agarbois to the freshwater cladoceran Daphnia magna was determined according to OECD Guideline 202 and EEC Directive 92/69/EECL383A.

 

The test was conducted under static - renewal conditions. Daphnia were not fed during the test.

 

Daphnia were exposed to a nominal range of concentrations 0, 32, 56, 100, 180 and 320 mg/l of Agarbois. The geometric means of the measured concentrations were between 78 and 91% of these nominal values.

 

The 24 and 48 hour EC50s of Agarbois based on the geometric mean of measured concentrations and calculated by the Probit method, are given below:

 

	EC50	95% Confidence	NOEC	Lowest Cone. Causing
24 hour	(mg/I)   130	Limits   110  - 150	(mg/I)   47	100% Mortality (mg/I)   290
48 hour	75	63 - 88	25	150