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Ecotoxicological information

Endpoint summary

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Additional information

Substance-specific data are available to meet a majority of the standard REACH information requirements for TAEE, however read-across to MTBE is used for the assessment of long-term toxicity in fish. When read-across is used from TAEE to MTBE a safety factor of 2 will be taken into account.)A general problem in testing the toxicity of TAEE to aquatic organisms is the volatility of the substance. The vapour pressure shows TAEE to be highly volatile and according to the Henry’s law constant the volatility from water is also very high. Volatilisation has been prevented as much as possible in the test designs and measured concentrations are essential when validating the tests.

A short-term toxicity test with TAEE is available for freshwater fish. The study is a semi-static GLP-compliant OECD 203 guideline study with the rainbow trout Oncorhynchus mykiss. The test concentrations were analytically verified but effect concentrations were based on nominal values. The 96-h LC50 is 240 mg/l (Harlan Laboratories, 2009f).

No long-term studies in fish are available for TAEE, an Early Life Stage test with eggs and larvae/fry of fathead minnow (Pimephales promelas) is available for MTBE (API, 1999). This result is used for read-across, the 31-d NOEC is 279 mg/l and a safety factor of 2 will be applied to this value. An effect concentration of 140 mg/l for TAEE will be used in the assessment.

One reliable study static GLP-compliant OECD 202 study with Daphnia magna is available for the short-term toxicity of TAEE to invertebrates (Brixham Environmental Laboratory, 2010a). The concentrations were analytically verified, the 48-h EC50 is 143.2 mg/l based on mean measured values.

For long-term toxicity test with invertebrates one study is available for TAEE. The study is a semi-static GLP-compliant OECD 211 study with Daphnia magna (Brixham Environmental Laboratory, 2010b). The concentrations were analytically verified, the 21-d NOEC is 22 mg/l.

A growth inhibition study with algae is available for TAEE. The study is a GLP-compliant OECD 201 study with Pseudokirchneriella subcapitata (Harlan Laboratories, 2009g). The concentrations were analytically verified, the 72-h ErC50 is 340 mg/l and 72-h NOEC for growth rate of 36 mg/l based on measured concentrations.