Registration Dossier
Registration Dossier
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EC number: 247-975-0 | CAS number: 26760-64-5
Short-term toxicity to aquatic invertebrates
Administrative data
Link to relevant study record(s)
Description of key information
The 48 hour EC50 value was 3.84 mg/l (95% confidence limits of 3.01 and 4.80 mg/l; measured concentration).
After 48 hours, the lowest measured concentration resulting in 100% immobility was 6.63 mg/l and the highest measured concentration at which immobilisation was </= 10% was 1.74 mg/l (NOEC).
Key value for chemical safety assessment
Fresh water invertebrates
Fresh water invertebrates
- Effect concentration:
- 3.84 mg/L
Additional information
One reliable proprietary freshwater study, Huntingdon (2004b) is available for the isomer 2-methylbut-2-ene (CAS 513-35-9). Since isoamylene (2-methylbutene, CAS 26760-64-5) is a mixture of the two isomers, 2-methylbut-2-ene (CAS 513-35-9) and 2-methylbut-1-ene (CAS 563-46-2) and in the absence of any reliable data for isoamylene the data for the isomer (CAS 513-35-9) are considered suitable for read-across.
The 48 hour EC50 value was 3.84 mg/l (95% confidence limits of 3.01 and 4.80 mg/l; measured concentration). After 48 hours, the lowest measured concentration resulting in 100% immobility was 6.63 mg/l and the highest measured concentration at which immobilisation was </= 10% was 1.74 mg/l (NOEC).
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