Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 201-143-3 | CAS number: 78-79-5
Long-term toxicity to fish
Administrative data
Link to relevant study record(s)
Description of key information
The 32 -day NOEC is 1.08 mg/L. TLM QSAR modelling was used to calculated NOELR values of isoprene towards fish. The calculated value NOELR values is 3.287 mg/L.
The lowest value was used for chemical safety assessment.
Key value for chemical safety assessment
Fresh water fish
Fresh water fish
- Effect concentration:
- 1.08 mg/L
Additional information
The long-term toxicity of isoprene to fish was determined by the OECD Toolbox on the basis of read-across from five nearest neighbours in the database on the assumption of Verhaar baseline toxicity. The OECD QSAR Toolbox was developed to increase the regulatory acceptance of (Q)SAR methods and to make (Q)SAR technology readily accessible, transparent and less demanding in terms of infrastructure costs. The OECD QSAR Toolbox was developed in cooperation with the European Chemicals Agency (ECHA) and therefore is considered to be a reliable source of data for this endpoint.
The ECOSAR model is a reliable and appropriate QSAR model to apply to isoprene as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity. A QSAR prediction was used as the key endpoint in the OECD SIDS for isoprene (2005).
For chronic toxicity to fish, no measured data for isoprene are available. This endpoint has been completed using a weight of evidence approach, including data from the OECD QSAR Toolbox, as well as QSAR results for isoprene. The OECD QSAR Toolbox reports a 768 hour NOEC of 1.08 mg/L based on growth rate, with the result read-across from five nearest neighbours to isoprene in OECD QSAR Toolbox database on the assumption of Verhaar baseline toxicity. The result reported in the OECD SIDS for isoprene is a ChV of 2.81 mg/L and the ECOSAR results for isoprene give a ChV of 1.76 mg/L. When divided by v2 (to adjust for ChV being a geometric mean of NOEC and LOEC), these ChV values correspond to long-term fish NOECs of 1.99 and 1.24 mg/L respectively.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
