C12-14 (even numbered) alkyl glycosides, oligomeric and C12-14 (even numbered) alkyl glycosides, oligomeric, carboxymethyl ethers, sodium salts

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vitro

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable in vitro testing method in pre-validation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Principles of method if other than guideline:

The principle of the testing method is based on the fact that measuring the amount of proteins with nucleophilic side chains such as cysteine or lysine residues after incubation with putative allergens may serve as surrogate markers for chemical reactivity associated with allergenic potency. In the Direct Peptide Reactivity Assay (DPRA) the reactivity of a test item towards synthetic cysteine (C)- or lysine (K)-containing peptides is evaluated. For this purpose the test substance is incubated with synthetic peptides for 24 hours at room temperature and the remaining non-depleted peptide concentration is determined by high performance liquid chromatography (HPLC) with gradient elution and UV-detection at 220 nm. The peptides are custom material containing phenylalanine to facilitate UV-detection and either cysteine or lysine as the reactive center.

GLP compliance:

no

Remarks:

In 2011, the method was still an in-house validated method.

Type of study:

other: Direct Peptide Reactivity Assay

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material (as cited in study report): Plantapon LGC Sorb
- Physical state: liquid, yellowish, clear
- Analytical purity: 31.1%
- Lot/batch No.: CE02480006

Results and discussion

Positive control results:

The positive control item p-benzoquinone showed a reactivity of 100% towards the cysteine-peptide and of 100% towards lysine-peptide. The mean reactivity for both depletions was 100%, indicating a high reactivity for this substance. Thus, as expected, the positive control substance was a strong sensitizer in the present in vitro assay.

In vitro / in chemico

Results

Parameter:

other: Migrated information from in vitro study

Remarks on result:

other: see Remark

Remarks:

Reading: other: not applicable. Group: test group. Dose level: 100 mM. Clinical observations: The test item showed a reactivity of -4% towards the cysteine-peptide and of-0.2% towards lysine-peptide. The mean reactivity for both depletions was 0, indicating a minimal reactivity of the test item and thus, the test item was a non-sensitizer..

Any other information on results incl. tables

For the test substance the mean peptide depletion as average of cysteine- and lysine-peptide depletions is calculated and summarized in the table below (negative depletions were considered to be “0” for calculation of the mean peptide depletion):

Table1: Mean Peptide Depletion

	Cysteine-Peptide		Lysine-Peptide		mean of both depletions
	[%]	SD	[%]	SD	[%]
p-Benzoquinone	100	0.0	100	0.0	100.0
Plantapon LGC Sorb	-4.0	5.1	-0.2	0.8	0.0

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

According to the classification tree model proposed by Gerberick et al. (2007), the test item was predicted to be a non sensitizer in the In vitro direct peptide reactivity assay.