3,7-dimethyl-1-octyl acetate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

experimental data of read across substances

Justification for type of information:

Data for the target chemical is summarized based on the structurally similar read across chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

WoE report is based on two short term toxicity to aquatic invertebrates studies as-
2. and 3.

GLP compliance:

not specified

Analytical monitoring:

no

Remarks:

2. no and 3. yes

Details on sampling:

2. no data available
3. - Concentrations: Test chemical conc. used for the study were 19.1, 34.3, 61.7, 111 and 200 mg/L (geometric ratio1.8), control.

Vehicle:

no

Remarks:

2. no and 3. not specified

Details on test solutions:

2. The stock solution 100 mg/l was prepared by dissolving colourless liquid in reconstituted water. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with reconstituted test water.

3. no data available

Test organisms (species):

Daphnia magna

Details on test organisms:

2.
TEST ORGANISM
- Common name: Water flea
- Strain: Straus
- Source: Own breeding at University of Chemistry and Technology, Prague
- Age at study initiation (mean and range, SD): The animals used for the test shall be less than 24 h old and should not be first brood progeny
- Feeding during test: No feeding

3. no data available

Test type:

other: 2. static and 3. semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

± 1 hr

Test temperature:

20±1°C

pH:

2. without adjustment
sample at concentration 50 mg/l : pH = 7.9 changed to pH = 7.8 during the test
control: pH = 7.9 did not change during the test

3. no data available

Dissolved oxygen:

2. higher than 7.7 mg/L at the end of test both in the control and the sample
3. no data available

Nominal and measured concentrations:

2. Nominal test chemical conc. used for the were 6, 10, 17, 29 and 50 mg/l, respectively.
3. 19.1, 34.3, 61.7, 111 and 200 mg/L

Details on test conditions:

2.
TEST SYSTEM
- Test vessel: 50 ml glass vessel
- fill volume: 25 ml
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
Natural water (surface or ground water), reconstituted water or dechlorinated tap water are acceptable as culturing and dilution water if D. magna survives in it for the duration of the culturing, acclimation and testing without showing signs of stress. Waters in the range pH 6 to pH 9, with hardness between 140 mg/l and 275 mg/l (as CaCO3) are recommended.
As an example, the preparation of dilution water meeting the requirements is described below.
Dissolve known quantities of reagents in water. The dilution water prepared shall have a pH of 7.8 ± 0.5, a hardness of (225 ± 50) mg/l (expressed as CaCO3), a molar Ca + Mg ratio close to 4 + 1 and a dissolved oxygen concentration above 7 mg/l.

Prepare the solutions specified below:
- Calcium chloride solution: Dissolve 117.6 g of calcium chloride dihydrate (CaCl2.2H2O) in water (4.2) and make up to 1 l with water (4.2).
- Magnesium sulfate solution: Dissolve 49.3 g of magnesium sulfate heptahydrate (MgSO4.7H2O) in water (4.2) and make up to 1 l with water (4.2).
- Sodium bicarbonate solution: Dissolve 25.9 g of sodium bicarbonate (NaHCO3) in water (4.2) and make up to 1 l with water (4.2).
- Potassium chloride solution: Dissolve 2.3 g of potassium chloride (KCI) in water (4.2) and make up to 1 l with water (4.2).

Mixing
Mix 2.5 ml of each of the four solutions and make up to 1 l with water.
The dilution water shall be aerated until the dissolved oxygen concentration has reached saturation and the pH has stabilized. If necessary, adjust the pH to 7.8 ± 0.5 by adding sodium hydroxide (NaOH) solution or hydrochloric acid (HCI). The dilution water prepared in this way shall not be further aerated before use.

- Sodium hydroxide solution, e.g. [NaOH] : 1 mol/l.
- Hydrochloric acid, e.g. [HCl] : 1 mol/l.

Reference substance:
Dissolve 600 mg of potassium dichromate (K2Cr2O7) in water and make up to 1 l with water (4.2).

OTHER TEST CONDITIONS
- Adjustment of pH: no adjustment done
- Photoperiod: Darkness

CALCULATION:
EC50 was calculated using non linear regression by the software Prism 4.0

3.
TEST SYSTEM
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: test liquid volume ca. 250 mL per vessel
- No. of organisms per vessel: 20 per conc. (5 per vessel)
- No. of vessels per concentration (replicates): 4 replicates

OTHER TEST CONDITIONS
- Photoperiod: room light, 16 hr light – 8 hr dark

TEST CONCENTRATIONS
- Test concentrations: Test chemical conc. used for the study were 19.1, 34.3, 61.7, 111 and 200 mg/L (geometric ratio1.8), control.

Reference substance (positive control):

yes

Remarks:

2. Potassium dichromate (K2Cr2O7) and 3. no data available

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

18.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 2. 95 % C. I. 16.4 to 21.3 mg/l

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

24.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 3. 95% C. I. – 15.5 to 29.2 mg/l (Measurement concentration (time-weighted average value) was adopted for calculation of effect concentration, because some measurement concentrations exceeded ±20 % of setting).

Results with reference substance (positive control):

2. - Results with reference substance valid
- EC50: 0.73 mg/L (24 hours)
3. no data available

Reported statistics and error estimates:

2. EC50 was calculated using non linear regression by the software Prism 4.0
3. no data available

Validity criteria fulfilled:

not specified

Conclusions:

On the basis of the experimental studies of the structurally and functionally similar read across chemical and applying the weight of evidence approach, the EC50 value the test chemical on the mobility of the test organism Daphnia magna can be expected to be ranges from 18.7 to 24.6 mg/l, respectively. Thus, based on the EC50 value, test chemical can be considered as toxic to aq. invertebrate. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to aq. invertebrate and thus can be considered to be not classified as per CLP classification criteria.

Executive summary:

Data available for the structurally and functionally similar read across chemicals has been reviewed to determine the toxic effect of the test chemical on aquatic invertebrates.The studies are as mentioned below:

An acute immobilisation test was conducted for 48 hrs for assessing the effect of test chemical on Daphnia magna. The test was performed in accordance to OECD guideline No. 202 “Daphnia sp.,Acute Immobilization Test”. Own breeding stock at University of Chemistry and Technology, Prague ofDaphnia magnawas used as a test organism for the study.The stock solution 100 mg/l was prepared by dissolving colourless liquid in reconstituted water. Test solutions of required concentrations, i.e, 6, 10, 17, 29 and 50 mg/l were prepared by mixing the stock solution of the test sample with reconstituted test water. Study was performed using total 100 daphnids (5 organisms per vessel/replicates) in a static fresh water system. Daphnids were exposed to test chemical in 50 ml glass vessel in a volume of 25 ml of liquid solution containing both the chemical and media. The beakers were placed in a room at a temperature of 20±1°C, pH 7.9 in dark conditions, respectively. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. On the basis of the effect of test chemical on the mobility of the test organism Daphnia magna, the 48 hr EC50 value was determined to be 18.7 mg/l with a 95% confidence interval value ranging from 16.4 to 21.3 mg/l, respectively.

In an another study, short term toxicity test was conducted for 48 hrs for assessing the effect of test chemical on Daphnia magna. The test was performed in accordance to OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used as a test organism for the study. Test chemical conc. used for the study were 19.1, 34.3, 61.7, 111 and 200 mg/L (geometric ratio1.8), control. Analytical monitoring involve the use of HS-GC. Study was performed using 20 per conc. (5 per vessel) Daphnia magna in a semi-static fresh water system. Total 100 fishes were exposed to test chemical in a closed vessel.The test vessels were placed in a room at a temperature of 20±1°C under a photoperiod of room light, 16:8 hr light: dark conditions, respectively.On the basis of mobility of the test organism Daphnia magna,the 48 hrs LC50 value was determined to be 24.6 mg/l (95% C. I. – 15.5 to 29.2 mg/l), respectively. 

On the basis of the experimental studies of the structurally and functionally similar read across chemical and applying the weight of evidence approach, the EC50 value the test chemical on the mobility of the test organism Daphnia magna can be expected to be ranges from 18.7 to 24.6 mg/l, respectively. Thus, based on the EC50 value, test chemical can be considered as toxic to aq. invertebrate. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to aq. invertebrate and thus can be considered to be not classified as per CLP classification criteria.

Description of key information

On the basis of the experimental studies of the structurally and functionally similar read across chemical and applying the weight of evidence approach, the EC50 value the test chemical on the mobility of the test organism Daphnia magna can be expected to be ranges from 18.7 to 24.6 mg/l, respectively. Thus, based on the EC50 value, test chemical can be considered as toxic to aq. invertebrate. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to aq. invertebrate and thus can be considered to be not classified as per CLP classification criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

18.7 mg/L

Additional information

Data available for the structurally and functionally similar read across chemicals has been reviewed to determine the toxic effect of the test chemical on aquatic invertebrates. The studies are as mentioned below:

 

An acute immobilisation test was conducted for 48 hrs for assessing the effect of test chemical on Daphnia magna. The test was performed in accordance to OECD guideline No. 202 “Daphnia sp.,Acute Immobilization Test”. Own breeding stock at University of Chemistry and Technology, Prague of Daphnia magna was used as a test organism for the study. The stock solution 100 mg/l was prepared by dissolving colourless liquid in reconstituted water. Test solutions of required concentrations, i.e, 6, 10, 17, 29 and 50 mg/l were prepared by mixing the stock solution of the test sample with reconstituted test water. Study was performed using total 100 daphnids (5 organisms per vessel/replicates) in a static fresh water system. Daphnids were exposed to test chemical in 50 ml glass vessel in a volume of 25 ml of liquid solution containing both the chemical and media. The beakers were placed in a room at a temperature of 20±1°C, pH 7.9 in dark conditions, respectively. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. On the basis of the effect of test chemical on the mobility of the test organism Daphnia magna, the 48 hr EC50 value was determined to be 18.7 mg/l with a 95% confidence interval value ranging from 16.4 to 21.3 mg/l, respectively.

 

In an another study, short term toxicity test was conducted for 48 hrs for assessing the effect of test chemical on Daphnia magna. The test was performed in accordance to OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used as a test organism for the study. Test chemical conc. used for the study were 19.1, 34.3, 61.7, 111 and 200 mg/L (geometric ratio1.8), control. Analytical monitoring involve the use of HS-GC. Study was performed using 20 per conc. (5 per vessel) Daphnia magna in a semi-static fresh water system. Total 100 fishes were exposed to test chemical in a closed vessel. The test vessels were placed in a room at a temperature of 20±1°C under a photoperiod of room light, 16:8 hr light: dark conditions, respectively. On the basis of mobility of the test organism Daphnia magna, the 48 hrs LC50 value was determined to be 24.6 mg/l (95% C. I. – 15.5 to 29.2 mg/l), respectively. 

 

On the basis of the experimental studies of the structurally and functionally similar read across chemical and applying the weight of evidence approach, the EC50 value the test chemical on the mobility of the test organism Daphnia magna can be expected to be ranges from 18.7 to 24.6 mg/l, respectively. Thus, based on the EC50 value, test chemical can be considered as toxic to aq. invertebrate. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to aq. invertebrate and thus can be considered to be not classified as per CLP classification criteria.