Propanoic acid, 2-hydroxy-2-methyl-, 2-propen-1-yl 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:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

prop-2-en-1-yl 2-hydroxy-2-methylpropanoate

EC Number:

700-908-3

Cas Number:

19444-21-4

Molecular formula:

C7H12O3

IUPAC Name:

prop-2-en-1-yl 2-hydroxy-2-methylpropanoate

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations:
- Sampling method: 2 x 50 ml of each concentration
- Sample storage conditions before analysis: Room Temperature

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)

Calculated amounts of the stock solution to produce the desired test concentrations and calculated amoutns of DMF to achieve identical vehicle concentrations were given into the reconstituted water and were homogeneously distributed.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna STRAUS
- Strain: Clone 5
- Source: Derived from culture from Solvias AG Ecotox Center.
- Age at study initiation (mean and range, SD): <24 hours
- Size at study initiation (sieved through a 1220µm sieve): <1220µm


- Feeding during test
- Frequency: No feeding during the 48 hour test period.

Study design

Test type:

static

Water media type:

not specified

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

The water hardness of the freshly prepared test medium was determined at test initiation. The water hardness corresponded to 244 mg CaCO3/L.

Test temperature:

The water temperature was maintained constant throughout the duration of the test at 21 ± 1°C in all test concentrations.

pH:

The pH was 8.5 - 8.6 and 8.0 - 8.1 at the start and at the end of the exposure, respectively.

Dissolved oxygen:

The oxygen saturation was measured to be 101 - 102 % and 97 - 99 % at the start d at the end of the exposure, respectively.

Salinity:

No data

Nominal and measured concentrations:

Nominal test concentration were 6.25, 12.5, 25, 50 and 100 mg/L of CA 2215 A. The test item was homogeneously distributed in the test vessels at all test concentrations at the start of the test. The measured test concentrations of CA 2215 A were 6.2, 12.5, 24.1, 41.0 and 104.2 mg/L at the start of the expousure and 5.5, 11.5, 23.9, 41.2 and 104.5 mg test item/L at the end of exposure.

Details on test conditions:

TEST SYSTEM
- Test vessel: 150ml glass beaker
- Material, size, headspace, fill volume: 100ml of test solution

- No. of organisms per vessel: 5 daphnids were exposed per test vessel.
- No. of vessels per concentration (replicates): 4 replicates for the test concentrations
- No. of vessels per control (replicates): 4 replicates for the control
- No. of vessels per vehicle control (replicates): 4 replicates per vehicle


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water was used as test medium (M4-medium according to ELENDT)
- Intervals of water quality measurement: Start and end of test

OTHER TEST CONDITIONS

- Photoperiod: 16 hours light : 8 hours dark with a 30 min. transistion period
- Light intensity: 1200 lux

EFFECT PARAMETERS MEASURED : Immobilization and other behavioural changes of the daphnids were recorded after 24 and 48 hours of exposure. Those animals not able to swim within 15 seconds after gentle agitation of the test container were considered to be immobile.

TEST CONCENTRATIONS

- Range finding study
- Test concentrations: 951.6mg of CA 2215 A wee mixed and made up to 10 ml with DMF (ML1). 1.0 ml of ML1 was mixed and made up to 10.0 ml with DMF (ML2). 1.0 ml of mL2 was mixed and made up to 10 ml with DMF (ML3). These solutions were used to prepare test solutions with test concentrations of 0.1, 1.0 and 10 mg/L, respectively.
- Results used to determine the conditions for the definitive study: 1.6033 g of CA 2215 A were mixed and made up to 10 ml with DMF (stock solution 1). 5 ml of stock solution 1 were mixed and made up to 10.0 ml with DMF (stock solution 2). 5 ml of stock solution 2 were mixed and made up to 10 ml with DMF (stock solution 3). 5 ml of stock solution 3 were mixed and made up to 10 ml with DMF (stock solution 4). 5 ml of stock solution 4 were mixed and made up to 10 ml with DMF (stock solution 5). These stock solutions were used to prepare test solutions with test concentrations of 1.0, 2.0, 4.0, 8.0 and 16.0 mg/L, respectively.
The following nominal concentrations were selected for the definitive test: Final test concentrations were 6.25, 12.5, 25.0, 50.0 and 100.0 mg/L of CA 2215 A

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 21.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL

Effect concentrations 2

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

ca. 24.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CL

Details on results:

- Other biological observations: At test concentrations of 6.25 mg/L no daphnids were immobiized after 24 hours and after 48 hours of exposure. Immobilization rates after 48 hours of exposure were 5, 75, 95 and 100% at test concentration of 12.5, 25, 50 and 100 mg?l , respectively.

- Mortality of control: No immobilization of daphnids was observed in the control (blank). In addition, during the biological phase of the study, no unexpected phenomena were recorded. Therefore, the validity criteria regarding the biology of the test were fulfilled.

Reported statistics and error estimates:

Probit Analysis
Variable : dead Control: (no) At time: 24 h
EC_XX and 95% confidence limits
PERC. EC (PERC) LOWER UPPER
(mg/L) (mg/L) mg/L)
0.05 12.4602 7.5498 16.0508
0.10 14.5054 9.5426 18.1175
0.20 17.4365 12.5819 21.1301
0.50 24.7952 20.3304 29.7871
0.80 35.2595 29.3915 46.9329
0.90 42.3842 34.4791 61.5219
0.95 49.3412 39.0235 77.5518

Summary:
Goodness-of-fit Tests
Statistics Value DF Prob>Chi-Sq
Pearson Chi-Square 3.9735 3 0.2643
Variable DF Estimate Std Err ChiSquare Pr>Chi
SLOPE: 1 2.39039142 0.46381 26.56179 0.0001
Control Rate = 0.0000

Variable : dead Control: (no) At time: 48 h
EC_XX and 95% confidence limits
PERC. EC (PERC) LOWER UPPER
(mg/L) (mg/L) mg/L)
0.05 11.1172 6.9289 14.1549
0.10 12.8522 8.6549 15.9032
0.20 15.3195 11.2477 18.4460
0.50 21.4363 17.6889 25.7162
0.80 29.9953 25.0737 39.7769
0.90 35.7537 29.1983 51.4884
0.95 41.3336 32.8656 64.1948

Summary:
Goodness-of-fit Tests
Statistics Value DF Prob>Chi-Sq
Pearson Chi-Square 2.5795 3 0.4611
Variable DF Estimate Std Err ChiSquare Pr>Chi
SLOPE: 1 2.50514874 0.485211 26.65661 0.0001
Control Rate = 0.0000

Any other information on results incl. tables

Biological Observations

Exposure period (h)	EC 50 (mg/L)	95 % confidence limit (mg/L)	Slope	No effect level (observed) (mg/L)
24 48	24.8 21.4	20.3 – 29.8 17.7 – 25.7	2.39 2.50	12.5 6.25

Immobilization of Daphnids after 24 and 48 hours of exposure

Initial number of daphnids per test concentration: 20

Concentration   nominal (mg/L)	Number of daphnia immobilized after 24 h of exposure
	Replicate:
	1	2	3	4	Total	%
Blank Vehicle 6.25 12.5 25 50 100	0 0 0 0 3 4 5	0 0 0 0 4 4 5	0 0 0 0 3 5 5	0 0 0 0 3 5 5	0 0 0 0 13 18 20	0 0 0 0 65 90 100

 

Concentration   nominal (mg/L)	Number of daphnia immobilized after 48 h of exposure
	Replicate:
	1	2	3	4	Total	%
Blank Vehicle 6.25 12.5 25 50 100	0 0 0 1 3 4 5	0 0 0 0 4 4 5	0 0 0 0 4 5 5	0 0 0 0 4 5 5	0 0 0 1 15 19 20	0 0 0 5 75 95 100

 

Measurement of Temperature, pH and Oxygen Saturation

Concentration nominal (mg/L)	0 h*			Final measurement 48 h
	pH	Oxygen (%)	Temp (°C)	pH	Oxygen (%)	Temp (°C)
Blank Vehicle 6.25 12.5 25 50 100	8.6 8.6 8.6 8.6 8.6 8.6 8.6	102 101 101 101 101 101 102	21.9	8.0 8.1 8.0 8.0 8.0 8.0 8.0	99 98 99 98 97 98 98	21.7

*Measured in separate beakers

Analytically determined Concentrations of CA 2215 A

Labelling of specimens CA 2215 A		Concentration of CA 2215 A (mg/L)	% of nominal concentration
Day 0 (0 h)	Blank Vehicle 6.25 mg/l 12.5 mg/l 25 mg/l 50 mg/l 100 mg/l	<0.04 <0.04 6.2 12.5 24.1 41.0 104.2	- - 99.2 100.0 96.4 82.0 104.2
Day 2 (48 h)	Blank Vehicle 6.25 mg/l 12.5 mg/l 25 mg/l 50 mg/l 100 mg/l	<0.04 <0.04 5.5 11.5 23.9 41.2 104.5	- - 88.0 92.0 95.6 82.4 104.5

Applicant's summary and conclusion

Conclusions:

The EC50 (48h) of CA 2215 A was determined to be 21.4mg/L based on nominal concentrations. The highest concentration with no observed effects was 6.25mg/L based on moninal concentrations.

Executive summary:

Test concentrations of nominal 6.25, 12.5, 25.0, 50.0 and 100.0mg/L of CA 2215 A were selected based on results of a range-finding test and a preliminary test. Exposure started when the daphnids were placed in the test vessel containing the test solutions. 

Twenty daphnids were exposed to each of the desired test concentrations under static conditions in M4-medium. For the test concentrations and the control, four replicates were performed. Each replicate consisted of five specimens in 100ml test solution. The daphnids were observed for immobilization and behavioural changes after 24 h and 48 h of exposure. 

The water temperature was maintained constant throughout the duration of the test at 21±1 °C in all test concentrations. The oxygen saturation was measured to be 101 -102 % and 97 – 99 % at the start and at the end of exposure, respectively. The pH was 8.5 – 8.6 and 8.0 – 8.1 at the start and at the end of exposure, respectively. 

The test item was homogeneously distributed in the test vessels at all test concentrations at the start of the test. The measured test concentrations of CA 2215 A were 6.2, 12.5, 24.12, 41.0, 104.2 mg/L at the start of exposure and 5.5, 11.5, 23.9, 41.2, 104.5 mg test item/L at the end of exposure. 

The total content of CA 2215 A was found 99.2, 100.0, 96.4, 82.0 and 104.2 % of nominal concentration at test begin and 88.0, 92.0, 95.6, 82.4 and 104.5 % at test end. 

Following values are based on nominal concentrations.

Exposure period (h)	EC 50 (mg/L)	95 % confidence limit (mg/L)	Slope	No effect level (observed) (mg/L)
24 48	24.8 21.4	20.3 – 29.8 17.7 – 25.7	2.39 2.50	12.5 6.25