Bis(2,3-epoxypropyl) terephthalate

Short-term toxicity to fish

Description of key information

Two studies were performed to determine the acute toxicity of bis(2,3-epoxypropyl)terephthalate to fish.
The first study was performed with a mixture containing at least 60% of the test substance in a static 96-hour acute toxicity study and a second study was performed on bis(2,3-epoxypropyl)terephthalate in a Semi-Static 96-hour Test according to OECD 203 and the Commission Regulation (EC) No 440/2008, C.1.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

5.5 mg/L

Additional information

In a first study TKK 30041, Araldite PT910 was test in an acute fish toxicity according to EEC directive 92/69, Part C.1. "Acute toxicity for fish"; and the OECD guideline No. 203: "Fish Acute Toxicity Test", adopted 17 July 1992.

The definitive test was performed with carp exposed to concentration ranging from 1.0 to 10 mg/L in a static system. Acetone was used as a solvent in the stock solution.

Since the test was performed with a mixture containing 60 to 100% of the substance and assuming that the effects observed are entirely due to the substance, by dividing the experimental LC50 for fish by 1.6 (corresponding to 60% of the substance) the resultant LC50 is around 5.5 mg/L. The substance is therefore considered to be toxic to fish.

In a second study the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss) was determined in a 96-hour semi static test based on the OECD Guideline No 203 and EU Method C.1.

A Filtrate of nominal 100 mg test item/L and a control were tested. Additionally, a filtrate of nominal 100 mg test item/L anddilutions of 1:2, 1:4, 1:8 and 1:16 and a control were tested, since all fish died in the first run.

The measurement of the concentration of the test item in the test samples collected in both biological tests clearly demonstrate that the test item was not stable during the renewal period of 24 hours. Additionally it can be clearly seen that it is not possible to adjust a constant concentration of the test item in the freshly prepared test media of the highest test concentration (= filtrate of 100 mg/L).Values of 0.57 to 2.7 mg test item/L were found during the 1^strun where all fishes died between 72 hours and 96 hours and values of 0.22 to 1.14 mg test item/ L were found during the 2^ndrun where all fishes survived.

The procedure to prepare a filtrate of a dispersion, which stirred only for 1 hour, was chosen due to the instability of the test item. The concentration of the hydrolysis products should be as low as possible in the freshly prepared test media. However, using this approach the concentration of the test item was highly variable.

Based on the test results the 96-hour test with bis(2,3-epoxypropyl)terephthalate on rainbow trouts (Oncorhynchus mykiss), the LC₀was determined in the second run and is 0.638 mg test item/L based on mean measured concentrations. The LC₁₀₀was determined in the first run and is 1.57 mg test item/L also based on mean measured concentrations. Since the test item concentrations were not reproducible during the test and as a large range of variability was observed (between 0.22 and 2.7 mg test item/L), no reliable LC₅₀could be determined.

As no reliable LC50 value could be determined in the semi-static test the LC50 value obtained in the static test with the mixture containing at least 60% ofbis(2,3-epoxypropyl)terephthalate and extrapolated to the worst case (all effects due to the substance) was taken into consideration for the key value for risk assessment.