1,3,6,8-Pyrenetetrasulfonic acid, sodium salt

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in chemico

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 442C (In Chemico Skin Sensitisation: Direct Peptide Reactivity Assay (DPRA))

GLP compliance:

yes (incl. QA statement)

Type of study:

other: direct peptide reactivity assay

Test material

Test material information

Constituent 1

Reference substance name:

1,3,6,8-Pyrenetetrasulfonic acid, sodium salt (1:4)

EC Number:

626-424-1

Cas Number:

59572-10-0

Molecular formula:

C16H16O12S4.4Na

IUPAC Name:

1,3,6,8-Pyrenetetrasulfonic acid, sodium salt (1:4)

Results and discussion

Positive control results:

The 100 mM stock solution of the positive control (cinnamic aldehyde) showed high reactivity towards the synthetic peptides. The mean depletion of both peptides was 65.55%.

In vitro / in chemico

Results

Results 1

Key result

Run / experiment:

other: Test IteM-Depletion of the Cysteine Peptide

Parameter:

other: Mean Peptide Depletion [%]

Value:

2.63

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Key result

Run / experiment:

other: Test Item-Depletion of the Lysine Peptide

Parameter:

other: Mean Peptide Depletion [%]

Value:

0.02

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

The in chemico direct peptide reactivity assay (DPRA) enables detection of the sensitising potential of a test item by quantifying the reactivity of test chemicals towards synthetic peptides containing either lysine or cysteine.
In the present study PTSA was dissolved in dist. water, based on the results of the pre-experiments. Based on a molecular weight of 610.43 g/mol a 100 mM stock solution was prepared.
The test item solutions were tested by incubating the samples with the peptides containing either cysteine or lysine for 24 ± 2 h at 25 ± 2.5 °C. Subsequently samples were analysed by HPLC. All test item solutions were freshly prepared immediately prior to use.
For the 100 mM stock solution of the test item no turbidity or precipitation was observed when diluted with the cysteine peptide solution. After the 24 h ± 2 h incubation period but prior to the HPLC analysis samples were inspected for precipitation, turbidity or phase separation. No precipitation, turbidity or phase separation was observed for any of the samples.
For the 100 mM stock solution of the test item no turbidity or precipitation was observed when diluted with the lysine peptide solution. After the 24 h ± 2 h incubation period but prior to the HPLC analysis samples were inspected for precipitation, turbidity or phase separation. No precipitation, turbidity or phase separation was observed for the samples of the test item. Phase separation was observed for the samples of the positive control (including the co-elution control). Samples were not centrifuged prior to the HPLC analysis.
Since the acceptance criteria for the depletion range of the positive control were fulfilled, the observed phase separation was regarded as not relevant.
No co-elution of test item with the peptide peaks was observed. Sensitising potential of the test item was predicted from the mean peptide depletion of both analysed peptides (cysteine and lysine) by comparing the peptide concentration of the test item treated samples to the corresponding reference control C (RC Cdist. water).
The 100 mM stock solution of the test item showed minimal reactivity towards the synthetic peptides. The mean depletion of both peptides was <= 6.38% (1.32%). Based on the prediction model 1 the test item can be considered as non-sensitiser.
The 100 mM stock solution of the positive control (cinnamic aldehyde) showed high reactivity towards the synthetic peptides. The mean depletion of both peptides was 65.55%.