Benzene, ethylenated, by-products from

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not applicable

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: study well reported but results not reported according to current guideline criteria.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPP 81-5 (Acute Dermal Irritation)

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: FIFRA Volume 43, #143 of the Federal Register, Aug. 22, 1978, Part 163.81-5. (EPA, Pesticide Programs: Proposed Guidelines for Registering Pesticides in the U.S.; Hazard Evaluation: Humans and Domestic Animals. Primary Dermal Irritation Study).

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: TSCA Volume 44, No.145 of the Federal Register, July 26, 1979, Part 772.112-25. (Environmental Protection Agency, Proposed Health Effects Test Standard for Toxic Substances Control Act Test Rules. Primary Dermal Irritation Study).

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: TSCA (Toxic Substances Control Act) : Health Effects Test Guidelines, Office of Toxic Substances, Office of Pesticide and Toxic Substances, United States Environmental Protection Agency, August 1982, Acute Exposure, Primary Dermal Irritation .

Principles of method if other than guideline:

Not applicable

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Details on test material:

Test substance: MCS-2170
Physical state: Yellow Liquid
Reference Number: NBP-2532690-B
Stored at Room Temperature
Density 0.97 g/ml

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hazleton-Dutchland Laboratory Animals Denver, Pennsylvania USA
- Age at study initiation: young adults
- Weight at study initiation:
- Housing: Individually housed during study in stainless steel cages
- Diet: ad libitum Purina Rabbit Laboratory Chow #5326
- Water: ad libitum
- Acclimation period: 36 or 37 days


ENVIRONMENTAL CONDITIONS
- Temperature (°F): 60-70 Deg Farenheit
- Humidity (%): 30-70%
- Photoperiod (hrs dark / hrs light): 12h day/night cycle

Test system

Type of coverage:

other: 4-hour interval: semi-occlusive covering. 24-hour interval: occlusive covering.

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):0.5 ml/site

Duration of treatment / exposure:

Single 4- or 24-hour exposure followed by a 7-14 day observation period.

Observation period:

Observations were made approximately 0, 4, 4.5, 28, 28.5, 52 and 72 hours then as necessary for Days 3-14, 2 times per day.

Number of animals:

Six rabbits for the 4-hour Exposure 24-hour Exposure

Details on study design:

TEST SITE
- Area of exposure: 4 sites, clipped intact skin of the back, on each rabbit
- % coverage: 10%
- Type of wrap if used: 4-hour exposure, Semi-occlusive. The appropriate amount of the test material was applied beneath a gauze square, 1"x1", placed directly on each of two test sites nearest the head of the rabbits and held in place with non-irri tating tape. Gauze was then wrapped around the animal and covered with porous tape, to semi-occlude the test sites.

24-hour exposure, Occlusive. The appropriate amount o f the test material was applied beneath a gauze square, 1 " x 1" , placed directly on each of two test sites posterior to the 4-hour sites and held in place with non-i rritating tape. Plastic sheeting was then wrapped around the animal and secured with tape to retard evaporation and keep the test material in contact with the skin without undue pressure. (The plastic and tape were placed so as not to interfere with the 4-hour sites).

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Following exposure, the wrappings and gauze squares were removed and the test site was gently wiped free of excess test material using water and gauze.
- Time after start of exposure: 4 hours or 24 hours exposures


SCORING SYSTEM: Draize method (Draize, J.H. 1959. The Appraisal of Chemicals in Foods, Drugs, and Cosmetics, p, 48. Association of Food and Drug Officials of the United States, Austin, Texas.)

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24 hour

Score:

4.6

Max. score:

8

Reversibility:

fully reversible within: 7 days

Irritant / corrosive response data:

Irritation was generally mild to moderate at the sites exposed for 4 hours under a semi-occlusive covering and moderate to severe at the sites exposed for 24 hours under an occlusive covering. Superficial tissue damage (transient or epidermal necrosis) was seen at one of the 4 hour sites in two o f the six animals and at one or both 24 -hour sites in all animals. All animals were free of significant irritation within 7 to 14 days after test material application.

Any other information on results incl. tables

SUMMARY OF DERMAL IRRITATION (INCIDENCE OF TISSUE DESTRUCTION, TIME TO RECOVERY)

Animal Number	Site	Tissue Destruction	Time to Clear
4-HOUR EXPOSURE
4988 F	RF	None	Day 7
	LF	None	Day 7
4986 F	RF	None	Day 7
	LF	Epidermal	Day 10
4987 M	RF	None	Day 7
	LF	None	Day 7
4974 F	RF	None	Day 10
	LF	None	Day 7
4962 F	RF	None	Day 10
	LF	None	Day 10
4965 M	RF	None	Day 14
	LF	Subepidermal	Day 14
24-HOUR EXPOSURE
4988 F	RB	Epidermal	Day 10
	LB	Epidermal	Day 10
4986 F	RB	Epidermal	Day 14
	LB	None	Day 10
4987 M	RB	Epidermal	Day 10
	LB	None	Day 10
4974 F	RB	Epidermal	Day 10
	LB	Epidermal	Day 10
4962 F	RB	Epidermal	Day 14
	LB	None	Day 10
4965 M	RB	Epidermal	Day 10
	LB	Epidermal	Day 10

Time clear represents interval at which significant dermal irritation was no longer present. If some

 irritation remained at termination of the study (Day 14), no interval is indicated.

RF=RightFront; LF=Left Front; RB=Right Back; LB=Left Back.

Irritation was generally mild to moderate at the sites exposed for 4 hours under a semi-occlusive covering and moderate to severe at the sites exposed for 24 hours under an occlusive covering. Superficial tissue damage (transient or epidermal necrosis) was seen at one of the 4 hour sites in two of the six animals and at one or both 24 -hour sites in all animals. All animals were free of significant irritation within 7 to 14 days after test material application.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

The primary irritation index for the 24-hour exposures was 4.6.

Executive summary:

Irritation was generally mild to moderate at the sites exposed for 4 hours under a semi-occlusive covering and moderate to severe at the sites exposed for 24 hours under an occlusive covering. Superficial tissue damage (transient or epidermal necrosis) was seen at one of the 4 hour sites in two of the six animals and at one or both 24 -hour sites in all animals. All animals were free of significant irritation within 7 to 14 days after test material application.