Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
dermal absorption
Type of information:
other: estimated by modeling on related Hydrotropes category
Adequacy of study:
key study
Study period:
2010
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Estimations based on state of the science modelling, not measurement

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report date:
2010

Materials and methods

Principles of method if other than guideline:
estimation by modelling

Test material

Constituent 1
Reference substance name:
Hydrotropes
IUPAC Name:
Hydrotropes
Details on test material:
The HYDROTOPE Category comprises the following 6 substances:
STS - Sodium toluene 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 cumene sulphonate (CAS 15763-76-5, EC 239-854-6)
KCS - Potassium cumene sulphonate (CAS 164524-02-1, EC 629-764-9)
NH4CS - Ammonium cumene sulphonate (CAS 37475-88-0, 253-519-1) 
In addition CaXS (Calcium Xylenesulphonate, CAS 28088-63-3, EC248-829-9) was evaluated for complete the assessment despite it is not registered under REACH.

Results and discussion

Percutaneous absorption
Key result
Parameter:
percentage
Absorption:
2.8 %
Remarks on result:
other:

Any other information on results incl. tables

The modelling results show that the uptake of hydrotropes from either a diluted solution, or the concentrated product, into the stratum corneum, for short exposure durations varies between 0.36% and 0.55% of the amount applied.

- % dermal absorption is independent of concentration (i.e., the dermal flux is not saturated) and skin contact area

- % dermal absorption increases with duration exposure

- for all concentrations, the 23 hour uptake efficiency is ca 2.8% for this exposure scenario (it is unlikely if not inconceivable that anyone would be exposed to a solution containing a hydrotrope for 23 hours without removal and/or washing of the exposed surface; therefore the 2.8% uptake efficiency would represent an upper bound value)

- a 2.8% dermal absorption factor can therefore be used as an upper bound value in the exposure dose calculation

Applicant's summary and conclusion

Conclusions:
Based on state-of-science modelling, a 2.8% dermal absorption factor can be used as an upper bound value in exposure dose calculations for hydrotropes.