Ethane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Information from review article and whilst the reliability is unknown, the original data are unpublished data from the Cosmetic Toiletry and Perfumery Association (CTFA). The data presented are detailed and adequate for assessment. Noting the test material is a gas, there are insufficient detail on how the material was applied. Contributes to a weight of evidence assessment.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Final report of the safety assessment of isobutane, isopentane, n-butane and propane

Author:

Anon

Year:

1982

Bibliographic source:

J American College of Toxicology, Volume 1, Number 4, 127-142

Reference 2

Reference Type:

other: submission report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: 16 CFR 1500.41

Principles of method if other than guideline:

Several formulations containing isobutane or a propane-isobutane mixture were tested for acute dermal irritation in rabbits according to 16 CFR 1500.41.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Isobutane

EC Number:

200-857-2

EC Name:

Isobutane

Cas Number:

75-28-5

Molecular formula:

C4H10

IUPAC Name:

isobutane

Constituent 2

Reference substance name:

Propane

EC Number:

200-827-9

EC Name:

Propane

Cas Number:

74-98-6

Molecular formula:

C3H8

IUPAC Name:

propane

Details on test material:

- Name of test material (as cited in study report):Formulations containing propane and isobutane were tested.

Test animals

Species:

rabbit

Strain:

not specified

Test system

Type of coverage:

not specified

Preparation of test site:

shaved

Vehicle:

not specified

Controls:

not specified

Amount / concentration applied:

The following concentrations of isobutane were tested: 83.20, 74.25, 75.75, 77.75, 80.75, 76.75, 84.55, 89.55, 75.75, 80.40, 78.55, 85.35, 80.75, 80.75 and 79.30%.
The following concentrations of isobutane:propane mixtures were tested: 65.94:12.56, 62.916:11.984, 65.44:12.46, 68.54:13.06, 65.562:12.488, 65.94:12.56%

Duration of treatment / exposure:

No data

Observation period:

72 hours

Number of animals:

6 per concentration

Details on study design:

Isobutane or isobutane:propane mixtures were applied to the shaved, intact skin on the back of each of a group of 6 rabbits. Erythema and oedema were assessed at 24 and 72 hours and the erythema and oedema scores calculated. The primary irritation index (PII) was calculated for each concentration and the skin irritation classified according to the following scheme: PII Score 0-2 = mildly irritating, 2-5 = moderately irritating, 6-8 = severely irritating.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24 and 72 hours

Score:

0.29 - 2.02

Reversibility:

no data

Remarks on result:

other: at isobutane concentrations ranging from 65.6% to 83.2%

Results 2

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24 and 72 hours

Score:

0.38 - 0.86

Reversibility:

no data

Remarks on result:

other: mixtures of isobutane:propane at following concentrations: 65.94:12.56, 62.916:11.984, 65.44:12.46, 68.54:13.06, 65.562:12.488, 65.94:12.56%

Any other information on results incl. tables

Ingredient	Concentration (%)	Primary Irritation Index
Isobutane	83.20	2.025
Isobutane/Propane	65.94/12.56	0.725
Isobutane/Propane	62.916/11.984	0.38
Isobutane/Propane	65.44/12.46	0.42
Isobutane	74.25	1.895
Isobutane	75.75	1.085
Isobutane/Propane	68.54/13.06	0.855
Isobutane	77.75	1.71
Isobutane	80.75	0.315
Isobutane/Propane	65.562/12.488	0.565
Isobutane	76.75	1.435
Isobutane	84.55	0.545
Isobutane	89.55	0.52
Isobutane/Propane	65.94/12.56	0.425
Isobutane	75.75	1.19
Isobutane	80.40	0.45
Isobutane	78.55	0.520
Isobutane	85.35	0.75
Isobutane	80.75	1.19
Isobutane	80.75	1.44
Isobutane	79.30	0.29

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Criteria used for interpretation of results: other: EU (GHS/CLP)

Conclusions:

When formulations containing isobutane (65.56-83.2%) or isobutane:propane mixtures (62.92-65.94% isobutane,11.984-13.06% propane ) were tested for acute dermal irritation, no to moderate erythema and oedema was seen and they were considered to be mostly mild skin irritants.

Executive summary:

When formulations containing isobutane (65.56-83.2%) or isobutane:propane mixtures (62.92-65.94% isobutane, 11.984 -13.06% propane) were tested for acute dermal irritation, no to moderate erythema and oedema was seen and they were considered to be mostly mild skin irritants.

Information from review article and whilst the reliability is unknown, the original data are unpublished data from the CTFA. The data presented are detailed and adequate for assessment. However, it is noted the test material is a gas and there are insufficient detail on how the material was actually applied.