Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Sulfonic acids that occur in nature are well documented to degrade quite fast and need to be neutralised to the salt form for further processing. Natural sulfonates are so complexed that attempts to separate out the sulfonate from the diluent oil may alter the composition and thousands of isomers may exist.

 

For synthetic sulfonate (such as alkaryl benzene sulphonates, including the registered substance), the substance is a UVCB with a wide variation of ABS isomers. Removal of the mineral oil solvent would considerably alter the composition of the technical grade substance.

 

The product with altered composition will impact the physico chemical studies, such as water solubility, partition coefficient, etc affecting the ability to obtain reliable data by testing. In addition, the presence of the mineral oil, the physical state is different from the physical state of the any isolated material.

Physico-chemical properties testing is technically not feasible, but where possible, the registrant has included the data from QSAR estimated on the basis of the structure of each of the alkylated benzene sulponates. An average result presented to allow for increased reliability and a category approach, as previously undertaken in the US EPA Right To Know initiative for HPV substances.

In the case of this substance, the presence of the mineral oil will not only affect the outcome of any physico-chemical study but also changes the physical properties of the substance, changing the physical state from solid to liquid. Testing this substance provides useful data for the purposes of establishing product characteristics for use, but will not provide any details of the intrinsic properties of the substance. Physico-chemical testing of the substance, as commercially available, is therefore not appropriate for registration.

In order to provide data on the intrinsic properties of the benzene sulphonic substance itself, in the absence of the mineral oil, data are presented by means of QSAR assessment of the chemical structure of the substance. In order to provide greater reliability of the QSAR data, several structural variation of the UVCB were assessed and a mean value assigned for each endpoint to be representative of the substance as a whole.