2-aminophenol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in chemico

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

publication

Title:

Assessment of Pre- and Pro-haptens Using Nonanimal Test Methods for Skin Sensitization

Author:

Urbisch D, Becker M, Honarvar N, Kolle SN, Mehling A, Teubner W, Wareing B and Landsiedel R

Year:

2016

Bibliographic source:

Chem. Res. Toxicol. 2016, 29, 901−913

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

The identity of the Cys-peptide adduct was identified by LC-MS

GLP compliance:

no

Type of study:

direct peptide reactivity assay (DPRA)

Test material

Test material information

Constituent 1

Reference substance name:

2-aminophenol

EC Number:

202-431-1

EC Name:

2-aminophenol

Cas Number:

95-55-6

Molecular formula:

C6H7NO

IUPAC Name:

2-aminophenol

Test material form:

solid

In chemico test system

Details on the study design:

A liquid chromatography−mass spectrometry (LC-MS) analysis was performed after a test chemical was
incubated with the Cys peptide to qualitatively distinguish adducts from peptide oxidation products.

For LC-MS analyses, the samples obtained from the standard DPRA procedure were stored in a freezer (−80 °C) and, after thawing, diluted 1:100 with water (HPLC grade) for final analyses. LC-MS analyses were performed using a TSQ 8000 Evo Triple Quadrupole mass spectrometer operated in the ESI(+) mode. An Ascentis C18 (50 × 2.1, 2.7 μm) was used as column for chromatographic separation. Mobile phase A consisted of 950 mL of acetonitrile mixed with 50 mL of water, and mobile phase B consisted of 950 mL of water, 50 mL of acetonitrile, and 0.1 mL of formic acid. The solvent flow rate was adjusted to 500 μL per minute with a gradient starting with 10% mobile phase A at t = 0 min and ending with 90% of the mobile phase A at t = 15 min. The divert valve was for the first minute and then from minutes 14 to 15. Mass spectra were acquired between minute 1 and minute 14 during the chromatographic run and assessed using Excalibur-Software (Thermo Fischer Scientific).The theoretical calculations of the massto- charge [m/z] ratios of the expected adducts were performed with ChemDraw Prime 15.0.

Results and discussion

In vitro / in chemico

Results

Parameter:

other: Peptide depletion (%)

Value:

59.7

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not specified

Remarks on result:

positive indication of skin sensitisation

Remarks:

plausible peptide adduct identified by mass spectrometry (z = 1 + z = 2); ortho-quinone imine formation and subsequent Michael addition

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

2-Aminophenol was found to bind to cysteine in a model peptide via the mechanism of ortho-quinone imine formation and subsequent michael addition.