4-oxo-4-(p-tolyl)butyric acid adduct with 4-ethylmorpholine

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10.04.1995 - 12.04.1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

An amount of test material (200 mg) was dissolved in 2 litres of reconstituted water with the aid of ultrsonic disruption to give a test concentration of 100 mg/l.
The concentration and stability of the test material in the test solutions were verified by chemical analysis at 0 and 48 hours.

Vehicle:

no

Details on test solutions:

For the purpose of the definitive study the test material was prepared by a direct dispersion in water.

Test organisms (species):

Daphnia magna

Details on test organisms:

The test was carried out using 1st instar Daphnia magna. Daphnia magna (Straus) were maintained in a laboratory culture originating from a strain supplied by the Institut National de Recherche Chimique Appliquée (I.R.CH.A.).
Adult Daphnia magna were maintained in polypropylene vessels containing approximately 2 litres of reconstituted water at a temperature of 21 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle. Each culture was fed daily with a suspension of mixed algae (predominantly Chlorella spp.). Culture conditions ensured that reproduction was by parthenogensis. Gravid adults were isolated 24 hours prior to the initioation of the test, the young daphnids produced overnight were then removed from the testing. The diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

2 d

Remarks on exposure duration:

Any immobilisation or adverse reactions to exposure were recorded at 24 and 48 hours after the start of exposure.

Hardness:

270 mg/l as CaCO3

Test temperature:

21 °C

pH:

7.8 +/- 0.2

Dissolved oxygen:

air-saturation value

Salinity:

25 ml of each solution a-d were added to each litre (final volume) of deionised water.
a) CaCl2 x 2H2O: 11.76 g/l
b) MgSO4 x 7H2O: 4.93 g/l
c) NaHCO3: 2.59 g/l
d) KCl: 0.23 g/l

Conductivity:

deionised water (conductivity <5 μS/cm)

Nominal and measured concentrations:

With respect to benzenebutanoic acid, 4-methyl-γ-oxo:
Vessel 1-2:
0 hours: nominal: 100 mg/l; measured: 106 mg/l
48 hours: nominal: 100 mg/l; measured: 104 mg/l

Vessel 3-4:
0 hours: nominal: 100 mg/l; measured: 106 mg/l
48 hours: nominal: 100 mg/l; measured: 106 mg/l

With respect to 4-ethylmorpholine:
Vessel 1-2:
0 hours: nominal: 100 mg/l; measured: 97.6 mg/l
48 hours: nominal: 100 mg/l; measured: 94.4 mg/l

Vessel 3-4:
0 hours: nominal: 100 mg/l; measured: 94.6 mg/l
48 hours: nominal: 100 mg/l; measured: 96.1 mg/l

Details on test conditions:

250 ml glass jars containing approximately 200 ml of test solution were used. At the start of the study 10 daphnids were placed in each test and control vessel at random, in prepared test solutions. Four replicate test vessels were prepared with duplicate control vessels. The test vessels were then covered to reduce evaporation and maintained at 21 °C with a photoperiod of 16 hours light and 8 hours darkness. The daphnids were not individually identified, received no food during exposure and the test vessels were not aerated.
The test solutions were not renewed during the exposure period. Any immobilisation or adverse reactions to exposure were recorded at 24 and 48 hours after the start of exposure. The criterion of effect used was that Daphnia were considered to be immobilised if they were unable to swim for approximately 15 seconds after gentle agitation.
Water termperature was recorded daily throughout the study. Dissolved oxygen concentrations and pH were recorded at the start and termination of the study. Water samples were taken from the control and the 100 mg/l test groups (replicates R1 and R2 pooled and replicates R3 and R4 pooled) at 0 and 48 hours for individual qualitative analysis of each of the chemical components in the test solutions.
An estimate of the EC50 values was given by inspection of the immobilisation data.

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

There was no immobilisation in 40 daphnids exposed to a test concentration of 100 mg/l for a period of 48 hours. The No Observed Effect Concentrations after 24 and 48 hours exposure were greater than or equal to 100 mg/l respectively. The No Observed Effect Concentration is based upon zero immobilisation at this concentration.
It was considered unnecessary and unrealistic to test at concentrations in excess of 100 mg/l.
There were no adverse reactions to exposure.
Temperature was maintained at 21 °C throughout the study. While there were no treatment related differences for oxygen concentration, a difference in pH was observed in the fresh test preparations at 0 hours between the control (mean pH = 7.7) and 100 mg/l test groups (mean pH = 6.7). After 48 hours the pH of the 100 mg/l test preparations was observed to have risen (mean pH = 7.1) compared to the 0 hour values, however the control values remained unchanged.
Analysis of the test solutions at 0 and 48 hours was carried out seperately for the chemical components benzene butanoic acid, 4-methyl-γ-oxo and 4-ethylmorpholine. The analysis showed measured test concentrations of both chemical components to be near nominal on both sampling occasions and so it was considered justifiable to estimate EC50 values in terms of nominal test concentrations only.

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of the test material to the freshwater invertebrate Daphnia magna has been investigated and gave a 58 hour EC50 of greater than 100 mg/l. Correspondingly the No Observed Effect Concentration was greater than or equal to 100 mg/l.

Executive summary:

A study was performed to assess the acute toxicity of the test material to Daphnia magna. The method followed that described in OECD Guidelines for testing of Chemicals (1984) No. 202, "Daphnia sp., Acute Immobilisation Test and Reproduction Test" referenced as Method C.2 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

Following a preliminary range-finding study, forty daphnids (4 replicates of 10 animals) were exposed to an aqueous dispersion of the test material at a concentration of 100 mg/l for 48 hours under static test conditions. Immobilisation and any adverse reactions to exposure were recorded after 24 and 48 hours.

The 48 hour EC50 for the test material to Daphnia magny based on nominal test concentrations was greater than 100 mg/l and correspondingly the No Observed Effect Concentration was greater than or equal to 100 mg/l.

It was considered unnecessary and unrealistic to test at concentrations in excess of 100 mg/l.

Individual analyis of each of the chemical components in the test solutions at 0 and 48 hours showed the measured test concentrations to be near nominal and so the results are based on nominal test concentrations only.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

13.02.1955 - 15.02.1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Details on sampling:

An amount of test material (100 mg) was dissolved in 1 litre of reconstituted water with the aid of ultrasonic disruption to give a 100 mg/l test concentration from which serial dilutions were made to give the test series.

Vehicle:

no

Details on test solutions:

In the range-finding study Daphnia magna were exposed to a series of nominal test concentrations of 0.1, 1, 10 and 100 mg/l. The test material was dispersed directly in water.

Test organisms (species):

Daphnia magna

Details on test organisms:

The test was carried out using 1st instar Daphnia magna. Daphnia magna (Straus) were maintained in a laboratory culture originating from a strain supplied by the Institut National de Recherche Chimique Appliquée (I.R.CH.A.).
Adult Daphnia magna were maintained in polypropylene vessels containing approximately 2 litres of reconstituted water at a temperature of 21 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle. Each culture was fed daily with a suspension of mixed algae (predominantly Chlorella spp.). Culture conditions ensured that reproduction was by parthenogensis. Gravid adults were isolated 24 hours prior to the initioation of the test, the young daphnids produced overnight were then removed from the testing. The diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

2 d

Remarks on exposure duration:

After 24 and 48 hours the number ob immobilised Daphnia magna were recorded.

Hardness:

270 mg/l as CaCO3

Test temperature:

21 °C

pH:

7.8 +/- 0.2

Dissolved oxygen:

air-saturation value

Salinity:

25 ml of each solution a-d were added to each litre (final volume) of deionised water.
a) CaCl2 x 2H2O: 11.76 g/l
b) MgSO4 x 7H2O: 4.93 g/l
c) NaHCO3: 2.59 g/l
d) KCl: 0.23 g/l

Conductivity:

deionised water (conductivity <5 μS/cm)

Nominal and measured concentrations:

0.1 mg/l
1 mg/l
10 mg/l
100 mg/l

Details on test conditions:

For each concentration 10 daphnids were placed in each test and control vessel and maintained at 21 °C with a photoperiod of 16 hours light and 8 hours darkness for a period of 48 hours. Each 250 ml test and control vessel contained 200 ml of test media and was covered to reduce evaporation. After 24 and 48 hours the number of immobilised Daphnia magna were recorded.

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Conclusions:

The results of the range-finding study showed no immobilisation at the test concentrations of 0.1, 1, 10 and 100 mg/l.

Executive summary:

Based on this information, a single test concentration of four replicates, of 100 mg/l was selected for the definitive study. This experimental design conforms to a "Limit test" to confirm that at the maximum test concentration given in the OECD/EEC Guidelines no immobilisation or adverse reactions to exposure were observed.

Description of key information

The acute toxicity of the test material to the freshwater invertebrate Daphnia magna has been investigated and gave a 58 hour EC50 of greater than 100 mg/l. Correspondingly the No Observed Effect Concentration was greater than or equal to 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L