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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 605-104-5 | CAS number: 157577-99-6
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
Description of key information
EC50 = 2000 mg/l, tested concentration
Key value for chemical safety assessment
- EC50 for freshwater algae:
- 2 000 mg/L
Additional information
One study (Stahl, ) was performed on similar substance 1 following EU C3 with a EC 50 at 72 based on Grow rate of 13.7 mg/l
Another study (Noack, 2011) was performed on similar substance 1 following a modified version of OECD. The EC0 is equal to 1 mg/l.
No effect on the algae toxicity is due to the counter ion and it is mainly due to the shadowing effect of the substance in the tested medium.
Several studies on algae conducted on dark dyes, including those with a modified test system for dye-stuffs, showed that the growth inhibition is not due to a toxic effect of the dye, but due to the light absorption of the stained water. Modified test system is usually conducted putting the dye above the algae testing solution, in a different vessel and not into contact with the alga. The same toxicity expressed as grow rate and yield inhibition has been observed like when in the same condition the algae is into contact with the dye. it has been deduced that the observed toxicity was related to the shading effect of the dye. This method has some limitation because it focuses on the shadow effect but gives no information on the real potential toxicity for algae of the tested substance.
One test has been conducted following OECD 221 on similar substance 1 usiang Lemna minor as aquatic plant.
Lemna is an aquatic plant that develops his leaves on the surface of the water, while nourishing substances are taken from the water solution. With this tests the observed effect is only related to the potential toxicity of the substance and not to the potential shading effect of a classical Alga study. A deviation to the protocol has been applied to the test recommended for dyes(Michael Cleuvers a, Hans-Toni Ratte, Phytotoxicity of coloured substances: is Lemna Duckweed an alternative to the algal growth inhibition test?Chemosphere 49 (2002) 9–15): "Beakers will be incubated on a black non-reflecting surface. Additionally, the walls of the incubation chambers will also be covered with black fabric in order to avoid reflection".
While for the same substance the “classical alga” test has provided a result of EC50 of 45.3 mg/l, with Lemna no toxicity up to the maximum tested level of 2000 mg/l on the active substance has been observed.
Therefore it can be assessed that the toxicity of the substance for Algae at 2000 mg/l and disregarding the already performed studies. This result is also in agreement with the studies on Daphnia and Fish performed on similar substance 1, that not revealed any toxicity at high levels of dosing.
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.
