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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 629-764-9 | CAS number: 164524-02-1
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
Description of key information
The HYDROTOPES Category comprises the following 6 substances:
STS - Sodium toluene 4-sulphonate (CAS 657-84-1, EC 211-522-5)
SXS - Sodium (xylenes and 4-ethylbenzene) sulphonate (EC 701-037-1)
NH4XS - Ammonium (xylenes and 4-ethylbenzene) sulphonate (EC 943-024-5)
SCS - Sodium p-cumenesulphonate (CAS 15763-76-5, EC 239-854-6)
KCS - Potassium p-cumenesulphonate (CAS 164524-02-1, EC 629-764-9)
NH4CS - Ammonium p-cumenesulphonate (CAS 680972-33-2, EC 811-484-5)
In addition CaXS (Calcium Xylenesulphonate, CAS 28088-63-3, EC 248-829-9) was evaluated for complete the assessment despite it is not registered under REACH.
There are available studies on short term toxicity to algae performed on the three subgroups (toluene, xylene and cumene).
The results of the availbale studies are:
STS (1995, GLP): EC50 72 h = 150 mg/l (a.i.)
SXS (1993, no GLP): EC50 96 h > 230 mg/l (a.i.)
CaXS (1994, GLP): EC50 96 h = 758 mg/l (a.i.)
SCS (2020, GLP): EC50 72 h > 100 mg/l (a.i.)
The key study used for the assessment is the test performed on SCS (2020, GLP) with the 72 hour EC50 value > 100 mg/L.
The other available studies are:
- reliable 1993 USEPA Guideline study (EPA OTS 797.1500 - Algal Toxicity). The freshwater Selenastrum sp. was exposed to a range of nominal concentrations of the test substance, sodium xylenesulphonate that reported a 96 -hour EC50 of >= 230 mg/L active substance based on cell density (with a 95% CL of 47 to 1200 mg/L). There was an apparent dose response and the 96-hour NOEC was 31 mg/L. The test substance was observed to be algistatic but not algicidal at the highest concentration tested (1000 mg/L active substance).
- a 1994 EPA Guideline study (EPA OTS 797.1500) with the test substance calcium xylenesulphonate was conducted under GLP requirements and with analytical confirmation reported a 96 hour EC50 of 758 mg/L active substance (with a 95% confidence limit of 592-924 mg/L) and a NOEC of 240 mg/L based on growth rate of Selenastrum sp.
- a 1995 EU Guideline study (EU C.3 Algal Inhibition Test) of sodium toluenesulphonate conducted under GLP requirements and with analytical confirmation reported a 72 -hour EbC50 of 150 mg/L active substance based on cell density and a 72 -hour ErC50 of 310 mg/L based on specific growth rate of Scenedesmus sp. The 72 -hour NOEC is 40 mg/L active substance based on biomass.
These studies indicate that of the Hydrotropes substances are comparable in term of effects on algae and show low toxicity.
Key value for chemical safety assessment
- EC50 for freshwater algae:
- 100 mg/L
- EC10 or NOEC for freshwater algae:
- 100 mg/L
Additional information
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.
