2-Propenoic acid, 2-isocyanatoethyl ester

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:

The experimental start and completion dates of the study were 4 June 2007 and 16 April 2008, respectively.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Remarks:

from MHRA (UK GLP Monitoring authority)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

482-140-6

EC Name:

-

Cas Number:

13641-96-8

Molecular formula:

Hill formula: C6 H7 N O3 CAS formula: C6 H7 N O3

IUPAC Name:

2-isocyanatoethyl prop-2-enoate

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test substance (100 mg) was dispersed in dilution medium in a volumetric flask (1 L).
The contents of the flask were shaken vigorously before being made up to volume and either
used directly at the highest test concentration (100 mg/L) or was diluted to provide the test
media at the lower concentrations of 4.27, 9.39, 20.7 and 45.5 mg/L.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Daphnia magna (Straus)
- Source: Daphnia magna (Straus) used in this study were cultured in-house and were obtained from a strain originating from the National Institute for Applied Chemical Research (IRCHA), France
- Age at study initiation: < 24 hours
- Method of breeding: Culture conditions ensure that the stock animals reproduce by parthenogenesis.

HOUSING
- HOUSING conditions: Stock cultures of Daphnia magna were maintained in glass vessels containing approximately 0.5 to 0.8 litres of Elendt M4 culture medium in a temperature-controlled laboratory at nominally 20 ± 2°C. A photoperiod of 16 hours light : 8 hours dark was maintained, with
periods of subdued lighting at the beginning and end of each light phase. The culture medium (Elendt M4 medium) was renewed three times each week.
- Type and amount of food: Cultures were fed with a suspension of the unicellular green algae, Pseudokirchneriella subcapitata, to provide nominally 0.1 to 0.2 mg carbon per daphnid, per day, except during the initial three days when a slightly lower ration was given.
- Feeding frequency: Daily

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

262 mg/L as CaCO3

Test temperature:

21.4 - 22.1 °C

pH:

7.24 - 7.75

Dissolved oxygen:

99- 100 % saturation

Nominal and measured concentrations:

Nominal concentrations: 4.27, 9.39, 20.7, 45.5 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: glass jars containing 100 ml of medium. The jars were loosely covered with watch glasses.
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to guideline


OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16 hours light : 8 hours dark


EFFECT PARAMETERS MEASURED: The numbers of mobile, immobile and floating Daphnia were counted approximately 24 and
48 hours after the start of the study.

TEST CONCENTRATIONS

- Results used to determine the conditions for the definitive study: The study comprised of three range finding tests followed by a definitive test with five test concentrations, plus a dilution medium control group.

In the first and second range finding tests, AOI was dissolved in dimethyl formamide before its addition to water and the tests employed nominal concentrations of 0.1, 1 and 10 mg/L. In the first test, the Daphnia were added to the test vessels containing the test media approximately 45 minutes after the test substance was first added to the dilution medium. In the second test, the animals were added to the dilution medium before the test substance was added (as a 10 µL aliquot). No immobility was observed in the first test but in the second test, all of the animals died at 10 mg/l but no immobilisation occurred at 0.1 or 1 mg/L after 48 hours.
In the second range finding test, samples were analysed immediately after dosing and again after approximately one hour. On this occasion of analysis, the result obtained for the procedural recovery sample was acceptable (96%) so the results of analysis for test samples have been quoted. A measurable level of AOI (ca. 0.853 mg/L) was found at a nominal 10 mg/L in the sample taken immediately after dosing; no AOI was detected in either of the
samples taken at 0.1 and 1 mg/L immediately after dosing, or in any of the samples taken one hour after dosing. These results confirmed that AOI was very unstable in the test dilution medium and that it was not possible to achieve or maintain exposure concentrations.

Following a review of the data, the results of the second range finding test, where the Daphnia had been placed in the test vessels before the test substance was added, were considered unrealistic because of the highly unstable nature of AOI following its addition to water. Consequently, it was decided to follow the guidance given in OECD Monograph Number 23 for the testing of unstable compounds. As the test substance had a half-life of
less than one hour, the test substance was allowed to degrade after its addition to water before the Daphnia were added.

The third test was conducted, without the use of solvent, to enable testing up to 100 mg/l. After 48 hours, all of the Daphnia at 100 mg/L and 20% of the Daphnia at 10 mg/L were immobile. Based on these results, the definitive test was conducted at nominal concentrations of 4.27, 9.39, 20.7, 45.5 and 100 mg/L.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

30.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

20.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Any other information on results incl. tables

The 48-hour EC50 of AOI for the immobilisation of Daphnia magna was 30.7 mg/l (95% confidence limits of 20.7 and 45.5 mg/l). The ‘no-observed effect concentration’ of AOI with Daphnia magna was 20.7 mg/l.