N,N-dimethylaniline

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Principles of method if other than guideline:

The objective of the study was to assess the irritant and/or corrosive effects of N, N-dimethylaniline (CAS No. - 121-69-7) after topical application on the intact skin in rabbits.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

N,N-dimethylaniline

EC Number:

204-493-5

EC Name:

N,N-dimethylaniline

Cas Number:

121-69-7

Molecular formula:

C8H11N

IUPAC Name:

N,N-dimethylaniline

Details on test material:

- Name of test material (as cited in study report):N, N-dimethylaniline
- Molecular formula :C8H11N
- Molecular weight :121.18 g/mol
- Substance type:Organic
- Physical state:Colourless Liquid
- Lot/batch No.:Lot 1/07
- Storage condition of test material:Store in a cool place. Keep container tightly closed in a dry and well ventilated place.
- Other:
Handling and Disposal
Safety precautions : Avoid Contact with skin and eyes. Keep away from sources of ignition. Aprons, masks, caps, gloves and goggles were used to ensure the health and safety of the personnel.
Disposal : The remaining unused test item was disposed as per internal SOPs of sa-FORD.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source:Procured from RABBI ROOF, Hyderabad.
- Age at study initiation:3.5 to 4.5 Months (Approximately)
- Weight (Prior to Treatment):Minimum: 2.228 kg & Maximum: 2.502 kg
- Health Status : Healthy young adults and nulliparous and non-pregnant Rabbits were used for the study.
- Housing:The animals were housed individually in stainless steel cages.
- Room Sanitation:The experimental room floor and work tops were swept and mopped with disinfectant solution every day.
- Cages and water bottle:All the cages and water bottles were changed minimum twice a week.
- Diet (e.g. ad libitum):All animals were provided conventional laboratory rabbit diet (Nutrivet Life Sciences, Pune) ad libitum.
- Water (e.g. ad libitum):Aqua guard filtered tap water was provided ad libitum.
- Acclimation period:Rabbits were acclimatised to the test conditions for a period of 5 days (Animal No.-1) and 8 days (Animal No.-2 and 3) prior to the application of the test item.

ENVIRONMENTAL CONDITIONS
- Temperature (°C):Minimum: 20.00 °C and Maximum: 22.50 °C
- Humidity (%):Minimum: 47.20 % and Maximum: 68.40 %
- Air changes (per hr):More than 12 changes per hour
- Photoperiod (hrs dark / hrs light):12:12

Test system

Type of coverage:

occlusive

Preparation of test site:

clipped

Vehicle:

not specified

Controls:

yes

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):0.5 ml
- Concentration (if solution):N/A

VEHICLE
- Amount(s) applied (volume or weight with unit):N/A
- Concentration (if solution):N/A
- Lot/batch no. (if required):N/A
- Purity:N/A

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

3 female rabbits

Details on study design:

TEST SITE
- Area of exposure:The dorsal lumbar region at contralateral sites.
- % coverage:Approximately 6 X 6 cm.
- Type of wrap if used:A porous gauze dressing and non-irritating tape (Micropore 3”).

REMOVAL OF TEST SUBSTANCE
- Washing (if done):The residual test item was removed by using cotton soaked in distilled water.
- Time after start of exposure:4 hour

SCORING SYSTEM:Draize Method

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: At 24 hours

Score:

0.33

Max. score:

3

Reversibility:

no data

Remarks on result:

other: not irritating

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: At 24 hours

Score:

0.33

Max. score:

3

Reversibility:

no data

Remarks on result:

other: not irritating

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: At 24 hours

Score:

0

Max. score:

3

Reversibility:

no data

Remarks on result:

other: not irritating

Results 4

Irritation parameter:

edema score

Basis:

animal: #1 ,#2 and #3

Time point:

other: At 24, 48 and 72 hours

Score:

0

Max. score:

3

Reversibility:

no data

Remarks on result:

other: not irritating

Irritant / corrosive response data:

The following were observed in treated rabbits.
The patch was removed after 4 hours and rabbits were observed for erythema and oedema at 1, 24, 48 and 72 hours after patch removal, evaluated and graded as per draize method.

After 4 hours of exposure in Animal No. 1 and 2, there were very slight erythema (barely perceptible) and no oedema observed at 1 and 24 hour of observation which was recovered to normal at 48 hours observation.

In Animals Nos. 3 at 1 hour observation after post patch removal, revealed, slight erythema (barely perceptible) and no oedema which was recovered to normal at 24 hours.

The individual mean score at 24, 48 and 72 hours for Animal Nos. 1, 2 and 3 were 0.33, 0.33, 0.00 and 0.00, 0.00, 0.00, for erythema and oedema formation, respectively.

Other effects:

Clinical Observation
No systemic toxicity was observed at treated rabbits during the experimental period.

Mortality
No mortality was observed during the observation period.

Any other information on results incl. tables

Table 1

Skin Reaction

 

In Treated area Dose:0.5 ml of test item                                                               Sex:Female

 

Animal No.	Test	Treated  area*	Erythema score				Oedema score
			1h	24h	48h	72h	1h	24h	48h	72h
1	Initial	Left	1	1	0	0	0	0	0	0
2	Confirmatory	Left	1	1	0	0	0	0	0	0
3		Left	1	0	0	0	0	0	0	0

 

 

 

In Control area                 Dose:0.5 ml of distilled water                              Sex:Female

 

Animal No.	Test	Treated area*	Erythema score				Oedema score
			1h	24h	48h	72h	1h	24h	48h	72h
1	Initial	Right	0	0	0	0	0	0	0	0
2	Confirmatory	Right	0	0	0	0	0	0	0	0
3		Right	0	0	0	0	0	0	0	0

Key: h = Hour.

Erythema                                                                                                       Oedema

0 =No erythema                                                                                           0 =No oedema

Table 1 Continued…

Mean Individual Animal Score at 24, 48 and 72 hours

 

Animal Number                   Observations	1	2	3
Erythema	0.33	0.33	0.00
Oedema	0.00	0.00	0.00

 

 

 

Table 2

Individual Animal BodyWeight

Sex:Female

Animal No.	Body Weight (kg)
	Prior to Dosing	At termination
1	2.502	2.540
2	2.228	2.352
3	2.474	2.522

Key: kg = Kilogram

Table 3

Individual AnimalClinicalSigns

Sex:Female

Animal No.	Days (Post dosing Observation)
	0	1	2	3
1	1	1	1	1
2	1	1	1	1
3	1	1	1	1

Key:1 = Normal.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

No erythema and oedema (skin irritation) were found at the end of 72 hour observation period after patch removal.
Hence, under the experimental test conditions, it was concluded that N, N-dimethylaniline (CAS No. - 121-69-7) was Non-Irritating to the skin of Female New Zealand White rabbits under the experimental conditions tested and being classified as “Category-Unclassified” as per CLP Regulation.

Executive summary:

Acute Dermal Irritation/corrosion Study of N, N-dimethylaniline (CAS No. - 121-69-7) in Rabbits, sponsored by Sustainability Support Services (Europe) AB was conducted at SA-FORD (Sanctuary for Research and Development), Maharashtra, India. This study was performed as per OECD guideline No. 404.

Three healthy young adult female rabbits were used for conducting acute dermal irritation study.Body weights were re­corded on day 0 (prior to application) and at termination.

Rabbits with good intact skin were selected for the study. The hairs of all the rabbits were clipped at contralateral sites, approximately 24 hours prior to treatment.A dose of0.5 ml of test item (as such) wasappliedto the skin,over an area of approximately 6 x 6 cm clippedof haironone side of rabbits.The other untreated side was kept as control area and0.5 ml of distilled water was applied at this site. At the end of 4 hours, the gauze patch was removed and test item application site was wiped with water without altering the integrity of the epidermis. 

Initially, the test item was applied to the clipped area of skin of one rabbit. The test site was covered with gauze patch.After 4 hours of exposure in Animal No. 1, there was very slight erythema (barely perceptible) and no oedema observed at 1 and 24 hour of observation. At 48 and 72 hour observation, no erythema and oedema was observed in animal No 1.Hence the confirmatory test was conducted on additional two rabbits (No. 2 and 3)to confirm the non irritant nature of the test item.

The patch was removed after 4 hours and rabbits wereobservedfor erythema and oedemaat 1, 24, 48 and 72 hours after patch removal, evaluatedand graded as per draize method.

In Animals Nos. 2 at 1 and 24 hours observation after post patch removal, revealed, slight erythema (barely perceptible)and no oedema which was recovered to normal at 48 hours observation.

In Animals Nos. 3 at 1 hour observation after post patch removal, revealed, slight erythema (barely perceptible)and no oedema which was recovered to normal at 24 hours.

At 48 and 72 hours observation no Erythema and oedema post patch removal in Animal nos. 2 and 3.

The individual mean score at24, 48 and 72 hoursfor Animal Nos. 1, 2 and 3 were 0.33, 0.33, 0.00 and 0.00, 0.00, 0.00, for erythema and oedema formation, respectively.  

Hence, under the experimental test conditions,it was concluded thatN, N-dimethylaniline(CAS No. - 121-69-7) was Non-Irritating to the skin of female New Zealand White rabbits under the experimental conditions tested and Classified as “Category- Unclassified” as per CLP Regulation.