Diisopropyl adipate

Endpoint summary

Description of key information

The skin sensitization potential of test chemical was assessed in various experimental studies conducted on human subjects. The predicted data using the Danish QSAR database has also been compared with the experimental data. Based on the available data for the test chemical and supporting studies, it can be concluded that the test chemical is unable to cause skin sensitization and thus can be considered as not sensitizing. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “non Skin Sensitizer”.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from publication

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

To determine skin sensitization potential of test chemical

GLP compliance:

not specified

Type of study:

other: Human Repeat Insult Patch Test

Justification for non-LLNA method:

Currently no LLNA study is available for assessment. The Human Repeat Insult Patch Test has been carried out as an animal test to predict human sensitization for over a decade and is recommended by international test guidelines such as OECD

Species:

other: Human

Strain:

other: not applicable

Sex:

male/female

Details on test animals and environmental conditions:

not specified

Route:

other: not specified

Vehicle:

not specified

Concentration / amount:

3.0%

Day(s)/duration:

24 h

Adequacy of induction:

not specified

No.:

#1

Route:

other: not specified

Vehicle:

not specified

Concentration / amount:

3.0 %

Day(s)/duration:

24 h

Adequacy of challenge:

not specified

No. of animals per dose:

50 men and women

Details on study design:

Details on study design
RANGE FINDING TESTS:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures:10
- Exposure period:24 h
- Test groups:55
- Control group: not specified
- Site:not specified
- Frequency of applications: not specified
- Duration: not specified
- Concentrations:3.0%

B. CHALLENGE EXPOSURE
- No. of exposures:1
- Day(s) of challenge:After 7 days of resting period,challenge patch was applied
- Exposure period:24 h
- Test groups:55
- Control group: not specified
- Site: not specified
- Concentrations:3.0%
- Evaluation (hr after challenge):24 and 48 h

Challenge controls:

not specified

Positive control substance(s):

not specified

Positive control results:

not specified

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

3.0%

No. with + reactions:

0

Total no. in group:

50

Remarks on result:

no indication of skin sensitisation

Interpretation of results:

other: not sensitizing

Conclusions:

Human Repeat Insult Patch Test was conducted on 50 male and female subjects to assess the skin sensitization potential of test chemical. A test was conducted using a suntan lotion containing
3.0% test chemical. During induction,10 patches were applied for exposure period of 24 hours. After a rest period of 7 days, a challenge patch was applied for exposure period of 24 hours.Observations were done after 24 and 48 hours. No skin sensitization reactions were produced in the 50 men and women panelists. Hence the test material was considered as not sensitizing to the human skin.

Executive summary:

Human Repeat Insult Patch Test was conducted on 50 male and female subjects to assess the skin sensitization potential of test chemical. A test was conducted using a suntan lotion containing 3.0% test chemical. During induction,10 patches were applied for exposure period of 24 hours. After a rest period of 7 days, a challenge patch was applied for exposure period of 24 hours.Observations were done after 24 and 48 hours. No skin sensitization reactions were produced in the 50 men and women panelists. Hence the test material was considered as not sensitizing to the human skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Various studies has been investigated for the test chemical to observe the potential for skin sensitization to a greater or lesser extent. The studies are based on in vivo experiments in human and guinea pigs for test chemical .The predicted data using the Danish QSAR database has also been compared with the experimental data and summarized as below:

Human Repeat Insult Patch Test was conducted on 50 male and female subjects to assess the skin sensitization potential of test chemical. A test was conducted using a suntan lotion containing 3.0% test chemical. During induction,10 patches were applied for exposure period of 24 hours. After a rest period of 7 days, a challenge patch was applied for exposure period of 24 hours.Observations were done after 24 and 48 hours. No skin sensitization reactions were produced in the 50 men and women panelists. Hence the test material was considered as not sensitizing to the human skin.

The above study was supported by Kligman maximization test was conducted on 25 male and female subjects to assess the contact sensitization potential of test chemical. A test was conducted using a facial cream containing 0.7% test chemical. The material was applied under occlusion to the skin of the volar forearm or back of 25 subjects for five consecutive 48 h periods. The patch site was then treated with 2.5% sodium lauryl sulfate for 24 h under occlusion. A challenge patch was then applied for 48 h and the site read immediately after patch removal and 24 h later. No contact sensitization reactions were produced in the 25 subjects. Hence the test material was considered as not sensitizing to the human skin.

Furthermore, Human Repeat Insult Patch Test was conducted on 116 male and female subjects to assess the skin sensitization potential of test chemical.The test chemical was applied dermally to the skin of human volunteers at a dose of 1.04% (0.1 ml).During induction,9 patches were applied for exposure period of 24 hours. After a rest period of 3 weeks, a challenge patch was applied for exposure period of 24 hours. Observations were done after 24 and 48 hours after removal of patch.If a challenge reaction occurred, a 2nd 24 h challenge was applied.The first insult produced faint erythema in 2 subjects while mild erythema in 1 subject. faint erythema occurred in four subjects after insult 2, in one after insult 3, and in one after insult 5. Mild erythema occurred in one person after insult 4. The challenge patch produced faint erythema in two persons after 24 h, and no reactions occurred after 48 h. No skin sensitization reactions were produced in the 116 men and women after 24 h. Hence the test material was considered as not sensitizing to the human skin.

Both the above studies were further supported by a Marzulli-Maibach repeat insult sensitization study was performed using a perfume on 235 male and female subjects to assess the skin sensitization potential of test chemical. A test was conducted using a perfume containing 1.08% of test chemical.The perfume (0.5 ml) was applied under occlusion to the skin of the upper backs of 235 men and women for 48 h (72 h on weekends). During induction,10 patches were applied for exposure period of 48 hours and every time new patches were applied to the same sites. After a rest period of 14 days, a challenge patch was applied for exposure period of 48 hours. The sites were scored on a scale of 0 (no reaction) to 5 (erythema with induration and bullae). During the induction series, one individual had erythema covering the entire test site and one had erythema with induration and vesiculation. This patient had no reaction when challenged. Seventeen subjects had slight hyperpigmentation, but no sensitization reaction occurred in any of the 235 volunteers. Hence the test material was considered as not sensitizing to the human skin.

According to Danish QSAR database, skin sensitization effects were estimated by using four different models i.e, Battery, Leadscope, SciQSAR and CASE Ultra for test chemical. Based on estimation, no Allergic Contact Dermatitis effects were observed when test chemical was exposed to human and guinea pig skin. Hence, the test chemical can be considered as not sensitizing to skin.

Based on the above summarized studies for target chemical,it can be concluded that the test chemical is unable to cause skin sensitization and considered as non-skin sensitizer. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Not Classified”.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The skin sensitization potential of test chemical were observed in various studies. From the results obtained from these studies it is concluded that the chemical is not likely to cause skin sensitization and hence can be classified as non-skin sensitizer.