Benzoic acid, 2-chloro-5-isocyanato-, 1,1-dimethyl-2-oxo-2-(2-propen-1-yloxy)ethyl 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

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

prop-2-en-1-yl 2-(2-chloro-5-isocyanatobenzoyloxy)-2-methylpropanoate

EC Number:

695-953-8

Cas Number:

204918-22-9

Molecular formula:

C15H14ClNO5

IUPAC Name:

prop-2-en-1-yl 2-(2-chloro-5-isocyanatobenzoyloxy)-2-methylpropanoate

Sampling and analysis

Analytical monitoring:

no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: Clone 5
- Source: Test facility laboratory
- Age at study initiation: <24 hours

Study design

Test type:

static

Total exposure duration:

48 h

Test conditions

Hardness:

214 mg/L CaCO3

Test temperature:

20°C ± 2°C, constant throughout the test within ± 1°C

pH:

8.0 - 8.1
Alkalinity: 0.8 mmol/l

Dissolved oxygen:

Saturation at the begining of the test. 96 - 100 % during the test.

Nominal and measured concentrations:

Nominal concentrations: 0.4, 0.9, 1.9, 4.3 and 9.4 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 ml beaers containing 100 ml test medium.
- No. of organisms per concentration: 20 Daphnia per concentration, two beakers per test concentration with 10 animlas each.
TEST MEDIUM / WATER PARAMETERS
The test medium was prepared with bi-distilled water and had the composition as detailed in Table 1.

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

EFFECT PARAMETERS MEASURED : For measurement refer to Table 3.
Oxygen: Oxygen content was measured at the start and at the end of the exposure period.
Temperature: Temperature was measured at the start and at the end of the exposure period.
pH: The pH was measured at the start and at the end of exposure period.
Immobilisation: The immobilisation of the Daphnia was recorded after 24 and 48 hours of exposure.
Those animals not able to swim within 15 seconds after gentle agitation of the test vessel were
considered immobile.

TEST CONCENTRATIONS
- Justification for using less concentrations than requested by guideline:
It was not possible to make a stock solution more concentrated than 10 % in DMF because of the
limited solubility of the test item CA 2814 B in DMF. Since the guidelines set the limit for the solvent
DMF at 0.01% in water, the test item concentration of 9.4 mg/L was the highest possible
concentration in the test.

- Range finding study: A range finding test was performed with concentrations of 0.1, 1.0 and 10 mg/L.

- Test concentrations: The main test was performed with nominal test item concentrations of 0.4, 0.9, 1.9, 4.3 and 9.4 mg/L in addition of blank control and a DMF control (0.01%), both without test item. Calculated amounts
of the stock solution were given into the test vessels to produce the desired test concentrations and
then made up to 200m with test medium. The200ml of test solutions were divided into two portions
of 10ml for each replicate test vessel.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 9.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

ca. 4.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 9.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

ca. 9.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

No immobilisation of the Daphnia was observed in the control and in the test item concentrations of 0.4, 0.9, 1.9 and 4.3 mg/L after the test period of 48 hours. Only at the highest test item concentration of 9.4 mg/L, 25 % of the Daphnia were immobilised after 48 hours. After 48 hours exposure no sublethal effects on the daphnia were recorded.

Number of immobilisaed daphnia after 24 and 48 hours refer to Table 2.

Results with reference substance (positive control):

Reference control on April 09, 2001: EC50 1.4 mg/L.

Reported statistics and error estimates:

Due to the absence of 50% mortality at the highest test item concentrations, the EC50 values were estimated without statistical program.

Any other information on results incl. tables

Table 2:

Mean measured concentration of test item (mg/L)	No of daphnia	No of immobilised daphnia		Immobility (%)
		24 h	48 h	24 h	48 h
Blank + DMF	10 10	0 0	0 0	0	0
Blank	10 10	0 0	0 0	0	0
0.4	V	0 0	0 0	0	0
0.9	10 10	0 0	0 0	0	0
1.9	10 10	0 0	0 0	0	0
4.3	10 10	0 0	0 0	0	0
9.4	10 10	0 0	3 2	0	25

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

not mote than 10% of the daphnia in the controls were immobilised

Conclusions:

The EC-values are based on the nominal concentrations of CA 2814 B:

Exposure period EC values (mg/L)
EC 0 EC 50 95% confidence limits of EC50
24 hours 9.4 >9.4 n.d
48 hours 4.3 >9.4 n.d
n.d.: could not be determined

Executive summary:

The water temperature was maintained at 20.2 – 21.0 °C throughout the exposure period in all test vessels. The oxygen content was in the range of 96 – 100% during the test and the pH ranged from 8.0 – 8.1. 

Since the test item is instable in water it was not possible to make a stock solution of CA 2814 Bin water (Pfeifle, 2001). Hence, N,N-Dimethylformamide (DMF) was used as solubilising agent for the preparation of a 10% stock solution (0.5 g CA 2814 B in 5 ml DMF). The following nominal concentrations were chosen for the definitive test 0.4, 0.9, 1.9, 4.3 and 9.4 mg/Lin addition to a blank control and a DMF-control, both without test item. It was not possible to make a stock solution more concentrated than 10 % in DMF because of the limited solubility of the test item CA 2814 B in DMF. Since the guidelines set the limit for the solvent DMF at 0.01% in water, the test item concentration of 9.4 mg/L was the highest possible concentration in the test. 

Due to the instability of the test item (Pfeifle, 2001), the actual test concentrations of CA 2814 B were not determined analytically. Hence, the results were calculated with the nominal concentrations. 

No immobilisation of the Daphnia was observed in the control and in the test item concentrations of 0.4, 0.9, 1.9 and 4.3 mg/L after the test period of 48 hours. Only at the highest test item concentration of 9.4 mg/L, 25 % of the Daphnia were immobilised after 48 hours. After 48 hours exposure no sublethal effects on the daphnia were recorded. 

 

The EC-values are based on the nominal concentrations of CA 2814 B:

 

Exposure period	EC values (mg/L)
	EC 0	EC 50	95% confidence limits of EC50
24 hours	9.4	>9.4	n.d
48 hours	4.3	>9.4	n.d

n.d.: could not be determined