2-aminopyridin-3-ol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

06.10.2003 - 03.05.2004

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

1

Reference substance name:

2-aminopyridin-3-ol

EC Number:

240-886-8

EC Name:

2-aminopyridin-3-ol

Cas Number:

16867-03-1

Molecular formula:

C5H6N2O

IUPAC Name:

2-aminopyridin-3-ol

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

Number of animals: 15 females (three groups of five females each group), nulliparous and non-pregnant.
Age and bodyweight: Young adult animals (approx. 11 weeks old} were selected. Body weight variation was within +/- 20% of the sex mean.
Identification: Tailmark.
Control animals: The vehicle control animals were treated using the same vehicle, using the same procedures and within the same time frame as this study.
Conditions:
Animals were housed in a controlled environment, in which optimal conditions were considered to be approximately 15 air changes per hour, a temperature of 21.0 ± 3.0°C (actual range: 19.3 - 21.4°C), a relative humidity of 30-70% (actual range: 33 - 72%) and 12 hours artificial fluorescent light and 12 hours darkness per day.
Cleaning procedures in the room might have caused the temporary fluctuations above the optimal maximum level of 70% for relative humidity. Based on laboratory historical data, these fluctuations were considered not to have affected the study integrity.
Accommodation:
Individual housing in labelled Macrolon cages (type I; height 12.5 cm) containing purified sawdust as bedding material (Woody-Clean type 3/4; Tecnilab-BMI BV, Someren, The Netherlands). Certificates of analysis were examined and then retained in the NOTOX archives. The acclimatisation period was at least 5 days before the start of treatment under laboratory conditions. Animals were group housed in polycarbonate cages (Macrolon II type; height 15 cm) during the acclimatisation period.
Diet:
Free access to standard pelleted laboratory animal diet (from Altromin (code VRF 1 ), Lage, Germany).
Water:
Free access to tap-water.

Study design: in vivo (LLNA)

Vehicle:

other: Ethanol : water (7:3 v/v)

Concentration:

0% (vehicle control), 5%, 25%, 50%

No. of animals per dose:

5

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

2.9

Test group / Remarks:

group 1, 5%

Results 2

Parameter:

SI

Value:

1.7

Test group / Remarks:

group 2, 25%

Results 3

Parameter:

SI

Value:

1.9

Test group / Remarks:

group 3, 50%

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

The Sl values calculated for the substance concentrations 5, 25 and 50% were 2.9, 1.7 and 1.9 respectively.
There was no indication that the test substance could elicit an SI ≥3.
Based on these results and according to the recommendations made in the test guidelines (OECD No.429, EC 8.42 and EPA OPPTS 870.2600), A 132 should not be regarded as a skin sensitiser.
Based on these results and according to the:
- OECD Harmonized lntegrated Hazard Classification System for Human Health and Environmental Effects of Chemical Substances (OECD, 1998), A 132 does not have to be classified for sensitisation by skin contact.
- EC criteria for classification and labelling requirements for dangerous substances and preparations (Council Directive 67/548/EEC), A 132 does not have to be classified and has no obligatory labelling requirement for sensitisation by skin contact.

Executive summary:

Assessment for Contact Hypersensitivity to A 132 in the Mouse (Local Lymph Node Assay).

The study was carried out based on the guidelines described in: OECD, Section 4, Health Effects, No.429 (2002), Paris Cedex; EC, Council Directive 67/548/EEC, Annex IV C, B.42 (Draft) (2001 ); Environmental Protection Agency (EPA): Health Effects Test Guidelines OPPTS 870.2600. "Skin Sensitisation" 2003.

Test substance concentrations selected for the main study were based on the results of a preliminary study.

In the main study, three groups of five experimental animals were epidermally exposed to a 5%, 25% and 50% concentration respectively on three consecutive days. Five vehicle control animals were similarly treated, but with vehicle alone (Ethanol:water (7:3 v/v).

Three days after the last exposure, all animals were injected with 3H-methyl thymidine and after five hours the draining (auricular) lymph nodes were excised.

After precipitating the DNA of the lymph node cells, radioactivity measurements were done.

All the nodes were equal in size.

Mean DPM/animal values for the experimental groups treated with test substance concentrations 5, 25 and 50% were 332, 192 and 220 respectively. The mean DPM/animal value for the vehicle control group was 113.

The SI values calculated for the substance concentrations 5, 25 and 50% were 2.9, 1. 7 and 1.9 respectively.

There was no indication that the test substance could elicit an SI ≥3.

Based on these results and according to the recommendations made in the test guidelines (OECD No.429, EC B.42 and EPA OPPTS 870.2600), A 132 should not be regarded as a skin sensitiser.

Based on these results and according to the:

- OECD Harmonized lntegrated Hazard Classification System for Human Health and Environmental Effects of Chemical Substances (OECD, 1998), A 132 does not have to be classified for sensitisation by skin contact.

- EC criteria for classification and labelling requirements for dangerous substances and preparations (Council Directive 67/548/EEC), A 132 does not have to be classified and has no obligatory labelling requirement for sensitisation by skin contact.