Benzene, bis(1-methylethyl)-, sulfonated, sodium salts

Short-term toxicity to fish

Description of key information

No acute fish study is available with SDIBP. The member of the hydrotrope substances support read-across of sodium xylene sulphonate (CAS No 28088-63 -3) data to SDIBP, in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5.. The nominal 96-hour LC50 was greater than the highest test concentration, 1000 mg/L.  No deaths or abnormal behavior were observed in the test at any of the 5 concentrations. 

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

1 000 mg/L

Additional information

There is no acute fish study available with SDIBP. A read-across was performed from sodium xylene sulphonate (CAS No 28088-63 -3), in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5. . The acute toxicity study with sodium xylene sulphonate (CAS No 1300-72-7) is considered the key study for SDIBP. The study was conducted in 1993 under USEPA Guideline - EPA-OTS 5797.1400 - Fish Acute Toxicity Test (Maura K Collins, 1993). The study is well documented, but was not conducted under GLP compliance. Rainbow trouts were exposed to the test substance for 96 hours in freshwater under static conditions. Chemical analysis was not performed. The nominal 96-hour LC50 was greater than the highest test concentration, 1000 mg/L. No deaths or abnormal behavior were observed in the test at any of the 5 concentrations.

Category Justification

According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances.

Applying the category approach read-across concept to SDIBP, data will be used from a representative member of the hydrotropes category to avoid unnecessary (animal) testing. The endpoints for which the read-across approach to SDIBP is applied, are: toxicokinetics, short-term toxicity to fish, toxicity to microorganism, acute toxicity (inhalation and dermal), skin irritation/corrosivity, skin sensitisation, genetic toxicity (in vitro, in vivo), repeated-dose toxicity (oral and dermal), screening for carcinogenicity, and screening for reproductive / developmental toxicity.

 

Environmental assessment related key information for SDIBP:

SDIPB and the hydroptrope members are considered to be hydrolytically stable, as they contain no chemical groups liable to hydrolysis. Furthermore, a low potential for bioaccumulation in aquatic and terrestrial organisms is expected, based on the low measured octanol/water partition coefficients (log Kow). Although the hydroptrope category is considered to be readily biodegrable and the available data on biodegradation of SDIPB only indicates inherently biodegradable, the supporting biodegradation data of SDIPB indicates that there is similar biodegradation potential.

Both SDIPB and the hydrotrope members are highly soluble in water and exhibit low acute toxicity to aquatic species. Hence it is deemed correct to fill the existing data gaps on environmental fate and ecotoxicity of SDIPB with the data of the hydrotrope category.