N-(n-octyl)-2-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 12 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:

publication

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:

Repeat Insult Patch Test in human volunteers

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

N-(n-octyl)-2-pyrrolidinone

EC Number:

403-700-8

EC Name:

N-(n-octyl)-2-pyrrolidinone

Cas Number:

2687-94-7

Molecular formula:

C12 H23 N O

IUPAC Name:

1-octylpyrrolidin-2-one

Details on test material:

Purity: not specified
Batch No.: not specified

Method

Type of population:

general

Ethical approval:

confirmed and informed consent free of coercion received

Subjects:

- Number of subjects exposed: 116
- Sex: 29 males and 87 females
- Age: from 16 to 69
- Race:
- Demographic information: 28 subjects are 18 to 30, 44 subjects are 31 to 45, 44 subjects are 46 to 69

- Other:

Clinical history:

Each subject completed an HRL History Form including relevant medical history. No subject was used if he or she exhibited any dermatological or other medical or physical condition which preclude topical application of the test material. No known pregnant nor nursing women were used on the Panel.

Route of administration:

dermal

Details on study design:

Patch preparation
The webril adhesive patch was used occlusively. Approximately 0.2 ml of the test substance was applied to each patch.

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

Patch schedule:
Induction schedule:
A series of nine Induction patches were applied for a period of three weeks on Mondays, Wednesdays and Fridays.
If a subject was unable to make the up a missed patching during the same week, the subject was repatched at the end of the Induction Phase (tenth visit). Additional absences necessitated dropping the subject from the Panel. Any absences and re-patchings are noted both by the date on each Individual Data Sheet and in the Addendum to the Report.
Subjects were instructed that each patch was to remain in place, and the area was to be kept dry for 24 hr, at which time the patch was to be removed. At 24-hr rest period, during which no test material was applied, followed the removal of the Monday and Wednesday patch applications; a 48 hr period followed the Friday patch application.
Each subject returned to HRL following the test period. The test area was observed by the HRL Project Manager, and the reaction scored and recorded, using the (modified) scoring scale of the International Contact Dermatitis Research Group System: Fisher, Alexander A., Contact Dermatitis Lea & Febiger, Philadelphia (1973) 29, as per HRL SOP.
The identical site was then re-patched until the nine Induction patchings were completed.

Rest period:
The rest period of approximately two weeks followed the application of the last induction patch; no test substance was applied during the rest period.

Challenge phase:
As per HRL SOP, the challenge patch was applied to a virgin site only. However, the original patch site was observed, and the subject queried as to whether any reaction was experienced during the rest period. Subjects were then instructed to keep the patches dry.
Each subject reported to HRL 24 hours later, at which time the patch was removed and the challenge was scored.
Each subject again reported to HRL at 48 hours and 72 hours post-patching for additional observation; reactions were scored and recorded.

Results and discussion

Results of examinations:

A total of 100 subjects, 26 male and 74 female, completed the test. Subjects ranged in age from 16 to 69: 26 subjects are 18 to 30, 34 subjects are 31 to 45, and 40 subjects are 46 to 69.
During the Induction Phase, sixty one subjects exhibited slight (+/- and/or 1 level) reactions. Several subjects exhibited hyperpigmentation and/or dryness.
The Original patch sites exhibited no reactions during the test period or at the Challenge.
At the Challenge Phase, three subjects exhibited slight (+/- level) reactions.

Applicant's summary and conclusion

Conclusions:

In this RIPT study, after repeated applications, the test substance did not induce contact dermal sensitization in human subjects.