N-(n-dodecyl)pyrrolidinone

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 03 Aug to 11 Sep 1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Limited study summary, no guideline and no GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Type of sensitisation studied:

skin

Study type:

study with volunteers

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Contact dermal photoallergy study: This comprised of an initial induction phase with dermal exposure to the substance, with and without irradiation, followed after a suitable rest period by a challenge phase of dermal exposure also with and without irradiation.

GLP compliance:

not specified

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

Batch No.: not specified
Purity: 1% aqueous suspension

Method

Type of population:

general

Ethical approval:

confirmed and informed consent free of coercion received

Subjects:

- Number of subjects exposed: 32
- Sex: 11 male and 21 female
- Age: From 17 to 69
- Race:
- Demographic information: 11 subjects are 17 to 30, 10 subjects are 31 to 45, 10 subjects are 46 to 66 and 1 subject is 69
- Other: At least six weeks had elapsed since a subject was patched in a Repeated Insult Patch Test or a photoallery study before he or she was used in this Photoallergy study.

Controls:

The other arm as the control was patched with the test substance but was not irradiated.

Route of administration:

dermal

Details on study design:

The webril adhesive patch was used occlusively. Approximately 0.2 mL of test material was applied to each patch.

Patch Sites
All patch sites were thoroughly cleansed with 70% isopropyl alcohol prior to each patching.

Induction Phase
As per HRL Standard Operating Procedure (SOP), patches were applied to the volar forearms starting proximal to distal using the radial aspect of the forearm.
One arm was patched with the test material and the test site (including an irradiation control site) was irradiated, as per schedule blow. The other arm was patched with the test material, but was not irradiated.
The right forearm was the irradiated arm for odd-numbered subjects: the left forearm was the irradiated arm for even numbered subjects.
The patch sites were recorded on the anatomical diagram of each subject’s individual data sheet.

Challenge Phase
As per HRL (SOP), the ulnar sides of the volar forearms were the virgin patch sites for the Challenge: patches (and control irradiation site) were adjacent to the original sites. The patch sites were recorded on the anatomical diagram of each subject’s individual data sheet.

Patching Schedule

Induction Phase
A series of six Induction patches were applied for a period of three weeks on Mondays and Thursdays. Each patch remained in place, and the subject was instructed to keep the patch dry for 24 hr, at which time the subject returned to HRL (on Tuesdays and Fridays). The Project Manager removed the patches, read the sites and recorded the scores of the patch sites on both arm. The designated forearm was irradiated and scored again immediately after irradiation. Test sites were marked with gentian violet. The identical sites were re-patched for the six induction patching and irradiations.
If a missed patching and/or irradiation was not made up during the same week, the subject was re-patched and irradiated at the end of the Induction Phase.
Wednesdays and weekends were rest days during the Induction Phase.

Rest Period
A rest period of approximately two weeks followed the application of the last Induction Patches; no test material was applied during the rest period.

Challenge Phase
As per HRL SOP, Challenge patches were applied to a virgin site only. The original patch sites were observed, and the subject queried as to whether any reaction was experienced during the rest period. Subjects were again instructed to keep the patches dry.
Each subject reported to HRL 24 hr later, at which time the patches were removed and the Challenge sites were scored by the HRL Project Manager. The designated forearm was irradiated with UV-A only and scored again immediately after irradiation. Subjects were again instructed to protect the non-irradiated arm from sunlight.
Each subject again reported to HRL at 48 hr and 72 hr post-patching (24 hr and 48 hr post-irradiation) for additional observation: reactions were scored and recorded.

Results and discussion

Results of examinations:

During the Induction Phase, nine subjects exhibited +/- level reaction on the irradiated contact sites. No reaction were exhibited on the irradiated non-contact sites. The irradiated sites (with and without test material) were observed to have slight tanning responses. Four subjects exhibited a +/- level reaction on the non-irradiated contact site.
The original patch sites exhibited no reaction during rest or at the Challenge.
No reactions were exhibited at the Challenge Phase.

Any other information on results incl. tables

PHOTOALLERGY MED DATA

Irradiated at: (Minutes; Seconds)

Subj	Skin Type	0:45	1:00	1:15	1:30	1:45	2:00	2:15	2 MED’s
01	Ⅰ	0	0	0.5	1.0	1.0	/	/	1:30
02	Ⅰ	0	0.5	1.0	1.0	1.0	/	/	1:15
03	Ⅱ	/	0.5	1.0	1.0	1.0	/	/	1:15
04	Ⅱ	/	0	0	0	0.5	1.0	/	2:00
05	Ⅱ	/	0	0	0	0.5	1.0	/	2:00
06	Ⅰ	DISCONTINUED
07	Ⅲ	/	/	0	0	0.5	1.0	1.0	2:15
08	Ⅰ	0	0	0	0.5	1.0	/	/	1:45
09	Ⅲ	/	/	0	0	0.5	1.0	1.0	2:00
10	Ⅲ	/	/	0	0	0.5	1.0	1.0	2:00
11	Ⅱ	/	0	0	0	0.5	1.0	/	2:00
12	Ⅱ	/	0	0	0	0.5	1.0	/	2:00
13	Ⅱ	/	0	0	0.5	1.0	1.0	/	1:45
14	Ⅱ	/	0	0	0.5	1.0	1.0	/	1:45
15	Ⅱ	/	0	0	0.5	1.0	1.0	/	1:45
16	Ⅲ	/	/	0	0	0.5	1.0	1.0	2:15
17	Ⅰ	0	0	0	0.5	1.0	/	/	1:45
18	Ⅱ	DISCONTINUED
19	Ⅱ	DISCONTINUED
20	Ⅱ	/	0.5	0.5	1.0	1.0	1.0	/	1:30
21	Ⅲ	/	/	0.5	1.0	1.0	1.0	1.0	1:45
22	Ⅱ	/	0.5	1.0	1.5	1.5	1.5	/	1:15
23	Ⅱ	/	0.5	1.0	1.5	1.5	1.5	/	1:15
24	Ⅲ	/	/	0	0.5	0.5	1.0	1.0	2:00
25	Ⅲ	/	/	0	0.5	0.5	1.0	1.0	2:00
26	Ⅲ	/	/	0	0.5	0.5	1.0	1.0	2:00
27	Ⅱ	DISCONTINUED
28	Ⅱ	DISCONTINUED
29	Ⅱ	DISCONTINUED
30	Ⅱ	/	0	0	0	0.5	1.0	/	2:00
31	Ⅰ	/	0.5	1.0	1.0	1.0	/	/	1:15
32	Ⅲ	/	/	0	0.5	0.5	1.0	1.0

N.B.: 2 MED’s are defined as irradiation time sufficient to achieve a 1.0 score, NOT double the time of the 0.5 Minimal Dose.

     / - Not irradiated at these times

Applicant's summary and conclusion

Conclusions:

The test substance when administered as a 1% aqueous suspension did not induce contact dermal photoallergy nor contact dermal sensitization in human subjects.