Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Short-term toxicity to fish

The acute toxicity of the test substance was investigated according to EU Method C.1 with Danio rerio for 96 hours (Bruns, 2002). The static freshwater test with a temperature of about 22.0 °C and a pH range of 7.2 - 7.8 resulted in a LC0 of 3160 mg/L, LC50 of 5621 mg/L and a LC100 of 10000 mg/L, respectively.

Furthermore, an acute toxicity study to fish of the read-across substance is available. Pimephales promelas was chosen as freshwater representative and was tested under static conditions, followed the methods of U.S. EPA. Ecological Research Series EPA-660/3-75-009 (Curtis et al., 1978). The basic scientific principles of fish tests which will be performed today are met. As result, a LC50(96h) value of 164.5 mg/L is reported.

Long-term toxicity to fish

The chronic toxicity for fish of 2,4,6 -triisopropyl-m-phenylene diisocyanate was not investigated experimentally. The Chronic Value (ChV) of 0.000365 mg/L was determined by the computer program ECOSAR v1.00 (Chemservice S.A., 2011). This value leads to a high toxicity concern; however, since it is defined as the geometric mean of the LOEC and NOEC, it is not taken into account for the risk assessment.

Short-term toxicity to aquatic invertebrates

Taken into account the read-across possibility of m-tolyidene to 2,4,6-triisopropyl-m-phenylene diisocyanate, which is scientifically justified (please refer to the read-across statement), experimental data are available for freshwater, marine and brackish water invertebrates.

For the freshwater compartment, Daphnia magna was used as test organism in two different experiments to investigate the acute toxicity of m-tolylidene diisocyanate according to OECD Guideline 202 (Tadokoro et al., 1997 and Caspers et al., 1986). The test duration was 48 hours, resulting in an EC50 value of 12.5 mg/L at a pH of 7.5. A final total TDA concentration of 5 mg/L was measured, which was expected before, due to the hydrolytic behaviour of TDI. The second experiment has to be considered as disregarded study, since the EC50 value was estimated as 750 mg/L. It was predicted, that a significant proportion of the test substance (ca. 35 %) would have been degraded at the start of the toxicity test and degradation would be virtually complete within several hours.

The marine invertebrate Americamysis bahia was also investigated according to OECD Guideline 202 (Tadokoro et al., 1997). Due to the hydrolytic behaviour of TDI, the substance would have been predominantly hydrolysed during this experiment. The medium contained about 6 mg/L TDA (mixture 2,4- and 2,6-isomers) at the concentration measured of the EC50 value. The EC50 value was determined as 18.3 mg/L.

Curtis et al. (1979) investigated the acute toxicity to the saltwater invertebrate Palaemonetes pugio under static test conditions. The test was performed in accordance to U.S. EPA. Ecological Research Series EPA-660/3-75-009. No significant mortality was observed until a test concentration of 508.3 mg/L. Other effects on test animals were not reported.

The brackish water invertebrate Nitocra spinipes was investigated by Bengtsson (1983). For the read-across substance a LC50(96h) of 11.8 mg/L with a 95 % confidence limit of 10.5 - 13.2 mg/L was determined.

Long-term toxicity to aquatic invertebrates

The chronic toxicity of m-tolylidene diisocyanate to aquatic invertebrates was investigated in two experiments with Daphnia magna according to OECD Guideline 211(key and supporting information). Furthermore, a QSAR prediction of 2,4,6 -triisopropyl-m-phenylene diisocyanate was performed.

In the key study, young female daphnids (less than 24 hours old) were exposed to nominal test concentrations of 0.28, 0.55, 1.10, 2.20 and 4.40 mg/L (Cerbelaut et.al., 1997). The NOEC for the test substance was defined as 1.1 mg/L. The supporting study is a limit test, whereby only test material concentrations up to 0.50 mg/L were tested. No effects were observed, therefore the EC50, LOEC and NOEC values were determined as greater or equal to 0.50 mg/L. The rapid hydrolysis rate of the test substance was considered in both experiments.

A long-term toxicity prediction for aquatic organisms of the substance 2,4,6 -triisopropyl-m-phenylene diisocyanate was performed by the computer program ECOSAR v1.00 (Chemservice S.A., 2011). For daphnids a Chronic Value (ChV) of 0.00121 mg/L was predicted.

Toxicity to aquatic algae and cyanobacteria

Acute toxicity test towards freshwater as well as marine water algae were investigated according to OECD Guideline 201 for the read-across substance m-tolylidene diisocyanate. The rapid hydrolysis rate of the test substance was taken into consideration when presenting the test results. Furthermore, a QSAR prediction was performed for green algae as supporting information.

The freshwater algae Chlorella vulgaris was investigated for a test duration of 96 hours, resulting in an EC50 of 4300 mg/L and a NOEC of 1000 mg/L (Tadokoro et al., 1997).

Regarding marine algae, an EC50 value of 3230 mg/L was determined using Skeletonema costatum (Tadokoro et al., 1997).

The prediction for long-term toxicity for aquatic organisms of the substance 2,4,6 -triisopropyl-m-phenylene diisocyanate was determined by the computer program ECOSAR v1.00 (Chemservice S.A., 2011). For green algae a Chronic Value (ChV) of 0.021 mg/L was predicted.

Toxicity to aquatic microorganisms

The acute toxicity to microorganisms of 2,4,6 -triisopropyl-m-phenylene diisocyanate was investigated in accordance with OECD Guideline 209 (Kanne, 1989). Activated sludge was used in the static freshwater experiment with an exposure time to the test substance of 3 hours. The EC50 value of greater or equal to 10000 mg/L is given as result, with the remark of water insolubility for the substance.

Toxicity to aquatic plants (other than algae) and other aquatic organisms

In accordance to REACH Regulation (EC) 1907/2006 this information is not mandatory for a registration of a chemical at a tonnage band of 100 - 1000 tons/year.