Registration Dossier
Registration Dossier
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: 201-604-9 | CAS number: 85-42-7
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
Description of key information
Algal growth inhibition: ErC50= 90.5 mg/L; EyC50 = 70.3 mg/L; NOEC = 46.9 mg/L
Key value for chemical safety assessment
- EC50 for freshwater algae:
- 90.5 mg/L
- EC10 or NOEC for freshwater algae:
- 46.9 mg/L
Additional information
Algal growth inhibitionto the unicellular
freshwater green alga Pseudokirchneriella subcapitata has been
investigated according to OECD/EU test methods. Hexahydrophthalic
anhydridewas found to inhibit the growth after 72 hours exposure, the
EbC50, ErC50 and EyC50 in non-adjusted media were 72.9 mg/L, 90.5 mg/L
and 70.3 mg/L, respectively. In pH-adjusted media, no inhibition
occurred during the test, so the EC50 value for all parameters was >91.9
mg/L. The “no observed effect concentration” (NOEC) for area under the
growth curve, growth rate and yield was 46.9 mg/L in non-adjusted media
and 91.9 mg/L in pH-adjusted media. These results suggest that the pH of
the test media, decreased by the presence of the test substance
following its degradation, was responsible for the toxicity observed in
the non- adjusted media.
In accordance with ECHA guidance oninformation requirements and chemical
safety assessment,Chapter R.7b: Endpoint specific guidance, theErC50
endpoint is used in DNEL derivation. This is because use of values based
on biomass cannot be applied to an analysis of results from a system in
exponential growth without logarithmic transformation.
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.
