Hydrocarbons, C7-C9, isoalkanes

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with generally accepted scientific standards and described in sufficient detail.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Type of sensitisation studied:

skin

Study type:

study with volunteers

Principles of method if other than guideline:

The irritant and sensitizing potential was tested in an intensified version of the Shelanski and Shelanski Repeated Insult Patch Test in more than 100 volunteers.

GLP compliance:

yes (incl. QA statement)

Remarks:

GCP

Test material

Test material information

Constituent 1

Reference substance name:

Hydrocarbons, C7-C9, isoalkanes

EC Number:

921-728-3

Cas Number:

64741-66-8

Molecular formula:

None available - not a single isomer - see remarks

IUPAC Name:

Hydrocarbons, C7-C9, isoalkanes

Details on test material:

- Name of test material (as cited in study report): MRD-88-294
- Physical state: clear,colorless liquid
- Analytical purity: 100% pure commercial product
- Other: Source Exxon Biomedical Sciences

Method

Type of population:

general

Ethical approval:

confirmed and informed consent free of coercion received

Subjects:

- Number of subjects exposed: 106 challenged
- Sex: 18 males, 88 females
- Age: males 22-79, females 20-82 years
- Race: no data

Clinical history:

- History of allergy or casuistics for study subject or populations: systemic illnesses contra-indicating participation in the study were excluded by the questionnaire

Controls:

none

Route of administration:

dermal

Details on study design:

TYPE OF TEST(S) USED: patch test (epicutaneous test)

ADMINISTRATION
- Type of application: semiocclusive (25 individuals had received a single occlusive application of neat test material one week before)
- Description of patch: 2 x 2" square of adhesive-faced impermeable plastic film with a 2 x 2 cm webril pad centered on it, later modified for partial occlusion by cutting the adhesive off of one pair of opposite sides
- Vehicle / solvent: undiluted in initial test, U.S.P. Petrolatum in actual sensitization study
- Concentrations: undiluted and 50 % w/w , respectively
- Volume applied: approx. 0.2 ml
- Testing/scoring schedule: Induction phase: 9 semiocclusive applications of test material and grading of responses always from Monday to Thursday, on Fridays only scoring of responses, after the 9th application the rest of that week was treatment-free; Challenge phase: starting on the following Monday, 4 semiocclusive applications were performed from Monday to Thursday on a new site, on Friday that contact site was examined and responses graded. Subsequently subjects were dismissed with instructions to examine induction and challenge sites for the next 2 weeks and to report changes to the investigator.
- Removal of test substance: yes, always before new application of test material and on Fridays


EXAMINATIONS
- Grading/Scoring system: see Table
- Statistical analysis: A Statistical Table for extrapolating the results of a Patch Test Study in various sized panels was given, which defines the upper and lower percentages of a general population which may, with 95 '% confidence, be expected to tolerate the test material if 0, 1, 2, 3 or 4 panelists were sensitized during the course of the patch test (Reference: Table IX, "Binomial Confidence Limits, Tables for Use with Binomial Samples", by Mainland et al. Department of Medical Statistics, New York University, College of medicine, 1956).

Results and discussion

Results of examinations:

SYMPTOMS
- Frequency, level, duration of symptoms observed: erythema grade 1 in 4/110 subjects, 24 h after 1st semiocclusive induction exposure


NO. OF PERSONS WITH/OUT REACTIONS COMPARED TO STUDY POPULATION
- Number of subjects with positive reactions: 0/106
- Number of subjects with negative reactions: 106/106
- Number of subjects with equivocal reactions: 0/106
- Number of subjects with irritating reactions: 4/110 (score 1)

Any other information on results incl. tables

Irritation potential:

The erythema which was seen in 4 subjects after the first exposure to 50% w/w test material in U.S.P. Petrolatum lacked the intensity, tenure and reproducibility to qualify the test material as skin irritant. The number of responders was insufficient to provide a 95% confidence level that the 50% preparation of the test material is different from a material incapable to produce any responses.

Sensitization potential:

There was no indication that the test material possesses a skin-sensitizing potential under the conditions of this study.

Applicant's summary and conclusion

Conclusions:

Under the test conditions, there was no evidence that the test material, hydrocarbons, C7 -C9, isoalkanes possesses a skin sensitizing potential.

Executive summary:

Under the test conditions, there was no evidence that the test material, hydrocarbons, C7 -C9, isoalkanes possesses a skin sensitizing potential.