Ethylene dibenzoate

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:

23-30 Nov 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Samples were taken for analysis from 0, 24, 48 and 72 hour fresh solution and 24, 48, 72 and 96 hour old solution.
Pretreatment method: The samples were diluted with acetonitrile 2-fold and then filtered with 0.45 μm membrane filter (nylon) for analysis. A blank control sample with test water was performed in parallel.

Vehicle:

no

Details on test solutions:

Method of preparation of test solution: A saturated solution method: 1.0001g ~ 1.0034g of test item was weighed and directly added into 10L test water, the solution was vigorously blended by magnetic stirring for about 48 hours. After magnetic stirring, the solution was filtered to remove undissolved test item, and about 5 L solution was collected for exposure.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

Test organism name: Zebra fish (Danio rerio)
Batch No.: Zebra fish 20170424
Origin: Qianmin plant, Shenyang
Reason for the selection of the test system: One of the recommended species of OECD and MEP, P.R. China Guideline for the Testing of Chemicals No.203
Holding Conditions:
Acclimation: During the first acclimation period of 12 days, there were not any sign of disease or mortalities. The fish were held in water of the quality to be used in the test during the acclimation period. During the following acclimation period, there were no sign of disease or mortalities.
Light condition: 12 hours light: 12 hours darkness
Temperature: 23±2 °C
Oxygen concentration: At least 80% of air saturation value (ASV)
Feeding: Twice on weekday and one time on weekend until 24 hours before the test was started

After 96 hours of exposure, all surviving fish were euthanized. The method of euthanasia was to put fish into a 0.5% water solution of ethylene glycol monophenyl ether.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

200 mg/L (as CaCO3)

Test temperature:

21.62 - 23.38 °C

pH:

7.71 - 8.26

Dissolved oxygen:

80.1 - 97.7 %ASV (air saturation value)

Nominal and measured concentrations:

Nominal test concentration: loading rate was 100 mg/L.
Measured concentration: 0.434 mg/L (geometric mean)

Details on test conditions:

TEST SYSTEM
- Test vessel: Rectangle glass tanks (length: 30 cm, width: 20 cm, height: 30 cm)
- Type: open
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: Criterion: loading <1.0 g fish /L water, total length: 3.0±1.0 cm; Results: 5 fish were sampled randomly before the test and determined for body length and weight. The range of body length: 2.6cm ~ 2.8cm,
the range of body weight: 0.1334g ~ 0.1732g.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Water prepared by using Aquapro Pure Water System
- Total organic carbon: < 2 mg/L
- Water hardness: 10 to 250 mg/L (as CaCO3)
- pH: 6.0 to 8.5
- Culture medium different from test medium: No
- Intervals of water quality measurement: The periodic measurements of TOC performed every three months
Aeration: Before usage, the water was aerated for more than 24 hours to attain dissolved oxygen saturation.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 12h light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality; Observation intervals: 3, 6, 24, 48, 72 and 96 hours after exposure

TEST CONCENTRATIONS
- Justification for using less concentrations than requested by guideline: Limit study at water solubility limit could be performed.
- Range finding study
- Results used to determine the conditions for the definitive study: no effects at the maximum water solubility

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.434 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

saturated solution

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

loading rate

Details on results:

During the 96-hour exposure period, no death and visible toxic signs were observed in the control group and the test group.

Results with reference substance (positive control):

24-hour LC50: 232.78 mg/L
95% confidence limits: 195.14-277.68 mg/L

Reported statistics and error estimates:

No statistics; limit test

Sublethal observations / clinical signs:

The analytical results showed that for the saturated test solutions, the arithmetic mean concentrations in fresh media were 2.516 mg/L, the determined concentrations in old media were lower than LOQ or no signal was detected. The mean exposure concentration over the whole period was calculated from the geometric mean concentration of each renewal period (24 hours) to be 0.434 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

According to the results of the test, the 96-hour LC50 of Ethylene glycol dibenzoate to Zebra fish (Danio rerio) was greater than 0.434 mg/L (geometric mean concentration), which was the saturated solution and equal to a loading rate of 100 mg/L, and no death and visible toxic signs were observed under this condition.

Executive summary:

A fish acute toxicity study of Ethylene glycol dibenzoate was conducted with Zebra fish (Danio rerio) over a 96-hour exposure period.

Based on the results of the preliminary test, the definitive test was carried out as a limit test at the maximum dissolved concentration of test item in test water with a loading amount of 100 mg/L. A concurrent blank control was performed in parallel. Seven fish were used for the test group and the control group, respectively.

The test was performed with a semi-static system, and test solutions were renewed every 24 hours. Dissolved oxygen and pH were measured daily during the 96-hour exposure period in the control and test solutions. The temperature was monitored continuously by an automatic temperature monitoring system and recorded at 1-hour intervals.

During the 96-hour exposure period, no death and visible toxic signs were observed in the control group and the test group.

The concentration of test item was determined in samples of test media by HPLC.For the saturated test solutions, the arithmetic mean concentrationsin fresh media were 2.516 mg/L, the determined concentrations in old media were lower than LOQ or no signal was detected. The mean exposure concentration over the whole period was calculated from the geometric mean concentration of each renewal period (24 hours) to be 0.434 mg/L.

According to the results of the test, the 96-hour LC₅₀of Ethylene glycol dibenzoate to Zebra fish (Danio rerio) was greater than 0.434 mg/L (geometric mean concentration), which was the saturated solution and equal to a loading rate of 100 mg/L, and no death and visible toxic signs were observed under this condition.

Description of key information

A acute fish study according to OECD 203 guideline under GLP was conducted with Zebra fish (Danio rerio) over a 96-hour exposure period.

Based on the results of the preliminary test, the definitive test was carried out as a limit test at the maximum dissolved concentration of test item in test water with a loading amount of 100 mg/L. Seven fish were used for the test group and the control group, respectively.

The test was performed with a semi-static system, and test solutions were renewed every 24 hours. During the 96-hour exposure period, no death and visible toxic signs were observed in the control group and the test group.

The mean exposure concentration over the whole period was calculated from the geometric mean concentration of each renewal period (24 hours) to be 0.434 mg/L.

According to the results of the test, the 96-hour LC₅₀of Ethylene glycol dibenzoate toZebra fish (Danio rerio) was greater than 0.434 mg/L (geometric mean concentration), which was the saturated solution and equal to a loading rate of 100 mg/L, and no death and visible toxic signs were observed under this condition.

This result is supported by a non-GLP OECD 236 study. Observations were made at 0, 24, 48, 72 and 96 hours. Coagulation of fertilized eggs, lack of somite formation, lack of detachment of the tail-bud from the yolk sac, and a lack of a heartbeat were scored as indicated by the test guideline as well as any other relevant effects. Solutions were refreshed every 24 hours by removing the majority of the liquid in the well and replacing with test substance freshly tapped from the WAF vessels. No chemical analyses were performed. LOELR = 10 mg/L and EL50 mg/L =>10<100 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L