Benzene-1,2:4,5-tetracarboxylic dianhydride

Endpoint summary

Description of key information

The registered substance is a highly reactive dianhydride hydrolyzing in water within approx. 20 minutes. Testing of the substance as such was not possible, therefore the corresponding Pyromellitic acid PMA was tested (read-across):

Short-term toxicity to fish

The study was performed to assess the acute toxicity of the test material to rainbow trout (Oncorhynchus mykiss). The method followed that described in the OECD Guidelines No. 203, "Fish, Acute Toxicity Test". The 96 -Hour LC50 based on mean measured test concentrations was greater than 100 mg/l and correspondingly the No Observed Effect Concentration was 100 mg/l.

Short-term toxicity to aquatic invertebrates

The study was performed to assess the acute toxicity of the test material to Daphnia magna. The method followed that described in the OECD Guidelines No 202, "Daphnia sp, Acute Immobilisation Test". The 48-Hour EC50 for the test material to Daphnia magna based on mean measured test concentrations was 63 mg/l with 95% confidence limits of 56 -71 mg/l. The No Observed Effect Concentration was 32 mg/l.

Acute toxicity to green algae

Key study:

The impact of the test item on the growth of the freshwater green algal species Pseudokirchneriella subcapitata (formerly Selenastrum capricornutum, occasionally also listed as Raphidocelis subcapitata) was investigated in a 72-hour static test according to the OECD Guideline 201 (adopted 2006, corrected 2011). The nominal test item concentrations tested were 6.25, 12.5, 25, 50 and 100 mg/L. A control (test water without test item) was tested in parallel.

At the start of the exposure, the measured concentrations of the test item in the test media for the concentrations of 50 and 100 mg/L were 103 and 106 % of the nominal values, respectively. At the end of the exposure, the measured concentrations in the test media for the concentrations 50 and 100 mg/L were 105 and 104 % of the nominal values, respectively. Thus, the analytical results confirm the correct dosage and stability of the test item over the exposure period of 72 hours. Therefore, the endpoint values were reported on the nominal concentrations of the test item.

In terms of growth rate, exposure of Pseudokirchneriella subcapitata to the test item gave an ErC50 (0 - 72 h) value of > 100 mg/L. The Lowest Observed Effect Concentration based on inhibition of growth rate was 100 mg/L and the No Observed Effect Concentration was 50 mg/L.

In terms of yield, exposure of Pseudokirchneriella subcapitata to the test item gave an EyC50(0 - 72 h) value of > 100 mg/L. The Lowest Observed Effect Concentration based on yield was100 mg/L and the No Observed Effect Concentration was 50 mg/L.

Supporting study:

In terms of growth rate, exposure of Desmodesmus subspicatus to the test material gave an ErC50 (0 - 72 h) value of 8.1 mg/l. The Lowest Observed Effect Concentration based on inhibition of growth rate was 12.5 mg/l and the No Observed Effect Concentration was 6.25 mg/l. In terms of yield, exposure of Desmodesmus subspicatus to the test material gave an EyC50(0 - 72 h) value of 7.9 mg/l. The Lowest Observed Effect Concentration based on yield was12.5 mg/l and the No Observed Effect Concentration was 6.25 mg/l. In terms of biomass integral (area under growth curve), exposure of Desmodesmus subspicatus to the test material gave an EbC50 (0 - 72 h) value of 8.8 mg/l The Lowest Observed Effect Concentration based on inhibition of biomass integral was 12.5 mg/l and the No Observed Effect Concentration was 6.25 mg/l.

This test was assessed as invalid by ECHA, therefore a new study was conducted.

Long term toxicity to aquatic invertebrates

The impact of the test item on the survival, growth (body length), and reproduction rate of Daphnia magna was investigated in a semi-static test over 21 days following the OECD TG 211. The nominal test item concentrations tested were 1.0, 3.2, 10, 32, and 100 mg/L. Additionally, a control group was tested in parallel. The biological results were based on mean measured concentrations, calculated as time-weighted means of the test item concentrations measured at the start of the test medium renewals and the concentrations measured in the samples at the end of the renewal periods.The samples from the nominal test concentrations of 1.0 to 10 mg/L were not analyzed, since these concentrations were below the NOEC determined in this test and, thus, were not relevant for the interpretation of the biological results. Taking into account the effects of the test item on survival, growth, and reproduction of the test animals, the overall 21-day NOEC was determined as 79 mg/L (mean measured), since no toxic effects were observed on the Daphnia magna at this and all lower test concentrations.

Additional information

Source: GLP-reports and expert assessments