(2-ethyl-2-methyl-1,3-dioxolan-4-yl)methyl prop-2-enoate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 Dec 2006 - 15 Dec 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1075 (Freshwater and Saltwater Fish Acute Toxicity Test)

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 09898602
- Expiration date of the lot/batch: 22 February 2007
- Storage: refrigerated, 1-10 °C
- Appearnce: yellow liquid

Analytical monitoring:

yes

Details on sampling:

30, 100, 300 mg/kg/day were selected, representing an approximate three-fold interval between dose levels.

Treated at Constant doses in mg/kg/day.

Volume dose 5 mL/kg body weight.

Individual dose volume Calculated from the most recently recorded scheduled body weight.


Method of preparation The required amount of test item was weighed. Where appropriate, starting with the lowest concentration, approximately 50% of the final volume of vehicle was
added and magnetically stirred until the test material was uniformly mixed. The remaining vehicle was added to achieve the required volume and the formulation was initially mixed using a high shear homogenizer and then using a magnetic stirrer for a minimum of 20 minutes.

A series of formulations at the required concentrations were prepared in ascending order.
Frequency of preparation Weekly. Storage of formulation Refrigerated (2 to 8°C).

Vehicle:

no

Details on test solutions:

At the start of the test and at each test media renewal, two discrete 100 mg/L stock solutions were prepared by adding 2 x 0.5 g of the test item to individual 5L volumetric flasks. Each flask was made up to volume with water and treated with ultrasound for 30 minutes, followed by an overnight stir in the dark. Following stirring, the stock solutions were pooled into a glass aquarium and mixed. All test media were prepared in duplicate, in nominal 15L constructed glass aquariums, by diluting appropriate volumes of the 100 mg/L stock media to achieve a final volume of 14L in each vessel.
A control treatment was prepared by adding 14L of water only into two nominal 15L constructed glass aquariums.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Oncorhynchus mykiss (rainbow trout)
- Source: Recognised supplier
- Length at study initiation (mean; range): 5.4 cm; 4.6 - 5.8 cm
- Weight at study initiation (mean; ange): 1.47 g; 0.939 - 1.88 g
- FIsh loading rate: < 0.8 g/L

ACCLIMATION
- Acclimation period: 45 days
- Acclimation conditions: same as test
- Type and amount of food during acclimation: proprietary fish food, (Trouw UK, Nutrafry)

FEEDING DURING TEST
- Food type: The fish were not fed during the test. The fish were starved for at least 48 hours before the start of the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

All fish in each test vessel were observed at ca 6 hours then at 24-hour intervals (24, 48, 72 and 96 hours)

Hardness:

71 - 82

Test temperature:

13.1 - 14.1

pH:

7.1 - 7.4

Dissolved oxygen:

93 - 100

Nominal and measured concentrations:

Range finder - Nominal (mg/L): 0.1, 1, 10, 100 and 1000
Definative - Nominal (mg/L): 0, 0.078, 0.16, 0.31, 0.63, 1.25, 2.5, 5.0 and 10
Definative - Measured (mg/L): 0.0647, 0.137, 0.282, 0.561, 1.14, 2.29, 4.56 and 9.53 (respectively corresponding to 83, 89, 91, 89, 91, 92, 91 and 95 % of the nominal concentrations)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aquariums
- Aeration: yes
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16-hour light, 8-hour dark

TEST CONCENTRATIONS
- Range finding study : yes
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

8.49 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

7.02 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Key result

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

1.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

1.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

1.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Details on results:

Formulation Analysis
The mean concentrations were within +10/-15% of the nominal concentration, confirming the
accuracy of formulation. The difference from mean and coefficient of variation remained
within 5%, confirming precise analysis.

Thyroid Hormone Analysis
The mean serum T4 concentrations in samples obtained from offspring on Day 13 of age and
F0 adult terminal male animals across all treatment groups were not significantly increased or
reduced when compared with the mean T4 concentration found in the control animals. There
was no statistically significant difference observed. Therefore, no effect of treatment is
inferred.

Results with reference substance (positive control):

Not specified

Reported statistics and error estimates:

A probit method of statistical analysis (Stephen et. al., 1978), performing a regression analysis of mortality against transformed (log10) nominal concentrations of the test item, as establishing the 50% lethal effect concentrations for each time point.
The NOEC and the 100% effect (mortality) concentrations were established from the fish daily observation records.

Sublethal observations / clinical signs:

The highest concentration at which no mortality occurred was 5.0 mg/L at 96 hours.

The lowest concentration at which 100% mortality occurred was 10 mg/L.

The validity criteria of control mortality being less than 10% and maintaining a dissolved oxygen concentration above 60% of the ASV were satisfied. Therefore the test was considered valid.

Validity criteria fulfilled:

yes

Conclusions:

The test item was found to be toxic to Oncorhynchus mykiss under the conditions described in this study. 96-hour LC50 and NOEC were 7.02 mg/L and 1.25 mg/L respectively.

Executive summary:

The objective of the study was to determine the 96-hour acute toxicity of the Subject Chemical to Oncorhynchus mykiss, conducted in accordance with the requirements of OPPTS Ecological Effects Test Guideline: 850.1075 Fish, Acute Toxicity Test, Freshwater and Marine.

 

The Subject Chemical was found to be toxic to Oncorhynchus mykiss under the conditions described in this study.

The 24, 48, 72 and 96-hour LC50 toxicity values are presented below, along with the NOEC values in terms of sub-lethal effects:

Toxicity values

Parameter       24- hour       48-hour       72-hour       96-hour

LC50        >10 mg/L       >10 mg/L       8.49 mg/L       7.02 mg/L

NOEC        1.25 mg/L       1.25 mg/L       1.25 mg/L       1.25 mg/L

 

The highest concentration at which no mortality occurred was 5.0 mg/Lat 96 hours. The lowest concentration at which 100% mortality occurred was 10 mg/L.

The validity criteria of control mortality being less than 10% and maintaining a dissolved oxygen concentration above 60% of the ASV were satisfied.

Description of key information

Acute Toxicity to Fish (96 hours):

LC₅₀: 7.02 mg/L

NOEC: 1.25 mg/L

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

7.02 mg/L

Additional information

A determination of the acute toxicity to fish of MEDOL-10 was conducted (Covance Laboratories Ltd, 2007, Study 2777/002-D2149). The study was performed in accordance with the EPA test guideline OPPTS 850.1075 and in compliance with GLP.

 

Following a preliminary range-finding test, groups of 7 rainbow trout (Oncorhynchus mykiss) were exposed to aqueous solutions of MEDOL-10 at nominal concentrations of 0, 0.078, 0.16, 0.31, 0.63, 1.25, 2.5, 5.0 and 10 mg/L for 96 hours at temperature of 14 °C, under semi-static test conditions in duplicate.

 

Analysis of the fresh and old test preparations showed the measured concentrations to be within the range of 80 – 120 %; hence, the results are expressed in terms of nominal concentrations.

 

The test item was found to be toxic to Oncorhynchus mykiss under the conditions. The highest concentration at which no mortality occurred was 5.0 mg/L at 96 hours, whereas the lowest concentration at which 100% mortality occurred was 10 mg/L. It was concluded that the 96-hour EC₅₀ and NOEC in Oncorhynchus mykiss were 7.02 and 1.25 mg/L, respectively.