1H-Perylo[3,4-cd]pyridine-1,3(2H)-dione

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation

Remarks:

in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline compliant

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Principles of method if other than guideline:

OECD guideline 406 is given in the report, which is probably an error and it is assumed that guideline 429 was followed.

GLP compliance:

yes

Remarks:

CENTRAL TOXICOLOGY LABORATORY, ALDERLEY PARK MACCLESFIELD, CHESHIRE UK

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

1H-benzo[10,5]anthra[2,1,9-def]isoquinoline-1,3(2H)-dione

EC Number:

608-929-9

Cas Number:

33955-44-1

Molecular formula:

C22H11NO2

IUPAC Name:

1H-benzo[10,5]anthra[2,1,9-def]isoquinoline-1,3(2H)-dione

Details on test material:

- Physical state: Powder
- Stability under test conditions: The stability of the test substance in propylene glycol for the duration of 24 hours was confirmed by analysis. The
stability of the test substance has been confirmed analytically.
- Storage condition of test material: Ambient temperature in the dark

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/Ca/Ola/Hsd

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan UK, Blackthorne, Bicester, Oxon, UK
- Age at study initiation: Young adults
- Weight at study initiation:
- Housing: A maximum of 4 mice was housed per cage, in cages suitable for animais of this strain and weight range
- Diet: RM 1, supplied by Special Diets Services Limnited, Withamn, Essex, UK, available ad libitum.
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3
- Humidity (%): 30-70
- Air changes (per hr): A minimum of 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

other: propylene glycol (test substance) and acetone (positive control)

Concentration:

3%, 10% or 30% w/v

No. of animals per dose:

4

Details on study design:

MAIN STUDY
- Criteria used to consider a positive response: The criterion for a positive response is that one or more concentrations of the test substance should elicit a 3-fold or greater increase in isotope incorporation relative to the vehicle control group.

TREATMENT PREPARATION AND ADMINISTRATION:
Approximately 25 µl of a 3%, 10% or 30% w/v preparation of the test substance in propylene glycol was applied, using a variable volume micro-pipette, to the dorsal surface of each ear. A vehicle control group was similarly treated using propylene glycol alone. The procedure was repeated daily for 3 consecutive days. A concurrent naive control group was not treated with the test substance or the vehicle.
Three days after the third application, all the animals were injected, via the tail vein, with approximately 250µl of phosphate buffered saline (PBS) containing approximately 20 µCi of a 2.0 Ci/mmol specific activity 3 H-methyl thymidine. Approximately 5 hours later, the animals were humanely killed by inhalation of halothane vapour followed by cervical dislocation. The draining auricular lymph nodes were removed from each animal and, together with the nodes from the other animals in the group, were placed in a container of PBS.
A single cell suspension was prepared by mechanical disaggregation of lymph nodes through a 200-mesh stainless steel gauze. The cell suspensions were then washed three times by centrifugation with approximately 10 ml of PBS. Approximately 3ml of 5% w/v trichloroacetic acid (TCA) was added and, after overnight precipitation at 4°C, the samples were pelleted by centrifugation and the supernatant was discarded. The cells were then resuspended in approximately 1ml of TCA.
The lymph node suspensions were transferred to scintillation vials and 10ml of scintillant (Optiphase) was added prior to 13-scintillation counting using a Packard Tri-Carb 2500TR Liquid Scintillation Counter.

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: see below

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see below

Any other information on results incl. tables

SKIN SENSITISATION POTENTIAL - TEST SUBSTANCE

Test item concentration	number of lymph nodes	Disintegrations per minute (dpm)	DPM/lymph node (x10^-2)	Test control ratio
Naive control	8	4753	5.94	N/A
vehicle control	8	4082	5.1	N/A
3 % (w/v)	8	4318	5.4	1.06
10 % (w/v)	8	4024	5.03	0.99
30 % (w/v)	8	5321	7.4	1.45

SKIN SENSITISATION POTENTIAL OF THE POSITIVE CONTROL SUBSTANCE

concentration of hexyleinnamaldehyde	number of lymph nodes	Disintegrations per minute (dpm)	DPM/lymph node (x10^-2)	Test control ratio
Naive control	8	2438	3.05	N/A
vehicle control	8	2881	3.6	N/A
1 % (w/v)	8	5975	7.47	2.08
3 % (w/v)	8	16126	20.16	5.6
10 % (w/v)	8	28732	35.92	9.98

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

In conclusion, the test article is unlikely to be a moderate or strong skin sensitiser under the conditions of the test.

Executive summary:

The test article was assessed for its skin sensitisation potential using the mouse Local Lymph Node Assay. The test substance was applied as 3%, 10% or 30% w/v preparations in propylene glyco1. The test substance did not have the capacity to cause skin sensitisation when applied as 3%, 10% or 30% w/v preparations in propylene glycol. In a positive control study, hexylcinnamaldehyde was shown to have the capacity to cause skin sensitisation when applied as 3% or 10% w/v preparations in acetone, confirming the validity of the protocol used for this study. In conclusion, the test substance is unlikely to be a moderate or strong skin sensitiser under the conditions of this test.