Bis(2,3-epoxypropyl) phthalate

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

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

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

A nominal amount of test item (1100 mg) was dispersed in 11 liters of test water with the aid of propeller stirring at approximately 1500 rpm for 24 hours. After 24 hours the stirring was stopped and any undissolved test item was removed by filtration through a 0.2 μm Sartorius filter (first approximate 1 liter discarded in order to pre-condition the filter) to give a 100% v/v saturated solution. A dilution was made from this saturated solution to give the test concentration of 10% v/v saturated solution.
The test preparation was mixed with a flat bladed stirrer for approximately 1 minute to ensure adequate mixing and homogeneity.
The concentration and stability of the test item in the test preparations were verified by chemical analysis of the fresh media at 0 and 72 hours and of the old media at 24 and 96 hours.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

14 degrees Celcius

pH:

7.3-7.7

Dissolved oxygen:

9.6-11.6

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 7.8 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

Exposure of rainbow trout (Oncorhynchus mykiss) to the test item gave LC50 values based on the mean measured test concentration of greater than 7.8 mg/L. The No Observed Effect Concentration was 7.8 mg/L.
Given that the mean measured test concentration was within 80% to 120% of the nominal test concentration of 9.4 mg/L, it was considered that the results of the threshold test were valid and confirmed that fish were not the most sensitive species.

Executive summary:

Introduction

A study was performed to assess the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss). The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No 203, "Fish, Acute Toxicity Test" referenced as Method C.1 of Commission Regulation (EC) No. 440.

Methods

Preliminary solubility work indicated that it was not possible to obtain a testable solution of the test item using traditional methods of preparation (e.g. ultrasonication and high shear mixing).

A preliminary media preparation trial indicated that a dissolved test item concentration of approximately 85 mg/L was obtained from a saturated solution method of preparation indicating this to be the limit of water solubility of this item under test conditions.

In accordance with the recommendations of REACh, the test was conducted according to the threshold approach recommended by ECHA. Using this approach the lowest EC50 value from either the Algal Growth Inhibition study or Acute Toxicity to Daphnia magna study is set as the threshold loading rate and a “Limit test” is conducted at this threshold loading rate. If no mortalities are observed this indicates that fish are not the most sensitive species and that the LC50 is greater than the threshold loading rate. The EC50 value obtained from the Algal Growth Inhibition study (Envigo Study Number LF83DP) was the lower of these two EC50values, and hence the test was conducted at a single nominal test concentration of 9.4 mg/L. Preliminary solubility work indicated that a 100% v/v saturated solution resulted in a measured concentration of 94 mg/L, and hence the test was conducted at a single concentration of 10% v/v saturated solution.

Seven fish were exposed to an aqueous solution of the test item, at a single concentration of 10% v/v saturated solution for a period of 96 hours at a temperature of 13 ºC to 15 °C under semi-static conditions. The test item solution was prepared by stirring an excess (100 mg/L) of test item in test water using a propeller stirrer at approximately 1500 rpm for 24 hours. After the stirring period any undissolved test item was removed by filtration (0.2 μm Sartorius Sartopore filter, first approximate 1 liter discarded in order to pre-condition the filter) to produce a saturated solution of the test item with a nominal concentration of 9.4 mg/L. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 1, 3 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

Results

Analysis of the fresh test preparations at 0 and 72 hours showed measured test concentrations to range from 7.80 to 8.33 mg/L. There was no significant change in the measured concentrations of the aged test preparations at 24 and 96 hours, so the results are based on mean measured test concentration only.

Exposure of rainbow trout (Oncorhynchus mykiss) to the test item gave LC50 values based on the mean measured test concentration of greater than 7.8 mg/L. The No Observed Effect Concentration was 7.8 mg/L.

Given that the mean measured test concentration was within 80% to 120% of the nominal test concentration of 9.4 mg/L, it was considered that the results of the threshold test were valid and confirmed that fish were not the most sensitive species.

Description of key information

Analysis of the fresh test preparations at 0 and 72 hours showed measured test concentrations to range from 7.80 to 8.33 mg/L. There was no significant change in the measured concentrations of the aged test preparations at 24 and 96 hours, so the results are based on mean measured test concentration only.

Exposure of rainbow trout (Oncorhynchus mykiss) to the test item gave LC50 values based on the mean measured test concentration of greater than 7.8 mg/L. The No Observed Effect Concentration was 7.8 mg/L.

Given that the mean measured test concentration was within 80% to 120% of the nominal test concentration of 9.4 mg/L, it was considered that the results of the threshold test were valid and confirmed that fish were not the most sensitive species.