Reaction products of alkenyl dihydrofuran-2,5-dione and polyisoalkenyl dihydro-2,5-furandione with alkylene glycol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 January 2014 to 22 January 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

Buehler test

Justification for non-LLNA method:

Justifications (1) company data on similar products (emulsifier component in soluble oil and semi-synthetic products) was based on the Buehler guinea pig skin sensitization test; (2) because of the test material contains unsaturated carbon-carbon double bond and fatty acids, literature data have demonstrated the LLNA producing false positives results for these types of chemicals; (3) to gain a definitive and experimentally based understanding of the skin sensitizing potential, a Buehler guinea pig skin sensitization test was conducted for the test material.

Test material

Reference

Name:

Unnamed

Type:

Constituent

Test material form:

liquid

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature in the dark

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male/female

Details on test animals and environmental conditions:

Forty-four male and 44 female Hartley-derived albino guinea pigs were received on 14 Jan 2014 from Charles River Laboratories, St. Constant, QC. The animals were examined and weighed on the day following receipt.
Each animal was identified by a cage card and plastic ear tag after receipt.
The animals were acclimated to their designated housing for at least 7 days before the first day of dosing.
The animals chosen for study were arbitrarily selected from healthy animals. All animals
received a detailed pretest observation prior to dosing. Only healthy animals were chosen for
study use.
The male range-finding animals were approximately 5 weeks of age on the day prior to dosing
with body weights of 354 g to 377 g. The female range-finding animals were approximately
6 weeks of age on the day prior to dosing with body weights of 358 g to 386 g.
The male main phase animals were approximately 6 weeks of age on the day prior to Induction 1 dosing with body weights ranging from 369 g to 488 g. The female main phase animals were approximately 7 weeks of age on the day prior to Induction 1 dosing with body weights ranging from 360 g to 436 g.
The animals were pair housed (2 animals of the same sex and same dosing group together) throughout the study in polycarbonate cages containing direct bedding material. Housing and care were as specified in the USDA Animal Welfare Act (9 CFR, Parts 1, 2, and 3) and as described in the Guide for the Care and Use of Laboratory Animals from the National Research Council.
Temperatures of 71°F to 74°F (22°C to 23°C) with a relative humidity of 39% to 49% were maintained. A 12-hour light/12-hour dark cycle was maintained, except when interrupted for designated procedures. Ten or greater air changes per hour with 100% fresh air (no air recirculation) were maintained in the animal rooms.
PMI Nutrition International Certified Guinea Pig Chow No. 5026 was provided ad libitum throughout the study.
Municipal tap water following treatment by reverse osmosis and ultraviolet irradiation was available ad libitum throughout the study. The water is analyzed semi-annually for microbial contamination and for total dissolved solids, hardness, and various environmental contaminants.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Induction 2

Concentration / amount:

The dose concentration for the main phase was based upon the results of the range-finding portion of the study (i.e. 100%).

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Challenge 2

Concentration / amount:

The dose concentration for the main phase was based upon the results of the range-finding portion of the study (i.e. 100%).

No. of animals per dose:

10 females + 10 males for the 100% test item
5 females + 5 males for the challenge control
5 females + 5 males for the rechallenge control
5 females + 5 males for the 2nd rechallenge control
5 females + 5 males for the HCA test
5 females + 5 males for the HCA control

Details on study design:

Main Phase: For the induction, challenge, rechallenge and second rechallenge phases, a dose of 0.3 mL (or maximum volume for viscous materials) will be placed on a 25-mm Hill Top
Chamber® backed by adhesive tape (occlusive patch). The chambers will then be applied to the
clipped surface as quickly as possible.
Main Phase Induction: On the day prior to the first induction dose administration (Day -1), the hair will be removed from the left side of the test animals with a small animal clipper. Care will be taken to avoid abrading the skin during the clipping procedures. On the day following clipping (Day 0), chambers containing the appropriate material will be applied to the clipped area of the test animals and α-Hexylcinnamaldehyde test animals. The induction procedure will be repeated on Day 7 (± 1 day) and Day 14 (± 1 day) so that a total of three consecutive induction exposures will be made to the test animals and α-Hexylcinnamaldehyde test animals.
The application site for induction may be moved if irritation persists from a previous induction exposure (to ensure the test article is not dosed on compromised skin) but will remain on the left side of the animal. Following chamber application, the trunk of the animal will be wrapped with elastic wrap which is secured with adhesive tape (if necessary) to prevent removal of the chamber.
Six hours after chamber application, the elastic wrap, tape, and chambers will be removed. The test sites will then be wiped 2 times with gauze moistened in mineral oil, followed by dry gauze and then wiped with gauze moistened in deionized water, followed by dry gauze, to remove test article residue. If the mineral oil followed by deionized water does not sufficiently remove the test article residue, the Study Director/Sponsor may choose to use another solvent.
Main Phase Challenge: On the day prior to challenge dose administration, the hair will be
removed from the right side of the test and challenge control animals and α-Hexylcinnamaldehyde test and control animals. Care will be taken to avoid abrading the skin
during the clipping procedures. On the day following clipping (Day 28 ± 1 day), chambers
containing the appropriate material will be applied to a naive site within the clipped area of the test and challenge control animals and α-Hexylcinnamaldehyde test and control animals.
Following chamber application, the trunk of the animal will be wrapped with elastic wrap which is secured with adhesive tape (if necessary) to prevent removal of the chamber.
Six hours after chamber application, the elastic wrap, tape, and chambers will be removed. The test sites will then be wiped 2 times with gauze moistened in mineral oil, followed by dry gauze and then wiped with gauze moistened in deionized water, followed by dry gauze, to remove test article residue. If the mineral oil followed by deionized water does not sufficiently remove the test article residue, the Study Director/Sponsor may choose to use another solvent.

Challenge controls:

The Challenge control is done with 0.3 mL of test item (100%) on two sites of 5 males and 5 females

Positive control substance(s):

yes

Remarks:

1, 2.5 and 5.0% (w/v) α-Hexylcinnamaldehyde (HCA) in Ethanol

Results and discussion

Positive control results:

Following challenge with 2.5% w/v HCA in acetone, dermal scores of 1 or 2 were noted in 10/10 HCA test animals at the 24-hour and 48-hour scoring intervals.
Following challenge with 1.0% w/v HCA in acetone, dermal scores of 1 or 2 were noted in 9/10 HCA test animals at the 24-hour scoring interval, and in 8/10 test animals at the 48-hour scoring interval.

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100%

No. with + reactions:

0

Total no. in group:

20

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

100%

No. with + reactions:

0

Total no. in group:

20

Results 3

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

5%

No. with + reactions:

10

Total no. in group:

10

Results 4

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

2.5%

No. with + reactions:

10

Total no. in group:

10

Results 5

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

100%

No. with + reactions:

0

Total no. in group:

10

Results 6

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

100%

No. with + reactions:

0

Total no. in group:

10

Results 7

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

1%

No. with + reactions:

9

Total no. in group:

10

Results 8

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

1%

No. with + reactions:

8

Total no. in group:

10

Any other information on results incl. tables

The sensitization potential of the test substance was based on the dermal responses observed on the test and control animals at challenge. Generally, dermal scores of ≥ 1 in the test animals with scores of 0 to ± noted in the controls were considered indicative of sensitization. Dermal scores of 1 in both the test and control animals were generally considered equivocal unless a higher dermal response (≥ grade 2) was noted in the test animals. Group mean dermal scores were calculated for challenge. A response of at least 15% in a nonadjuvant test is expected for a mild to moderate sensitizer in this study design.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The skin sensitisation potnetial of the test material was assessed in accordance with OECD Guideline 406. Based on the results of this study, the test material is not considered to be a contact sensitizer in guinea pigs, as the criterion for sensitization (dermal scores ≥ 1 in at least 15% of the test animals) was not met. The results of the HCA positive control study demonstrated that a valid test was performed and indicated that the test design would detect potential contact sensitizers. As such, the test material can be considered to be not sensitising and does not meet the GHS criteria for classification.

Executive summary:

Guideline

OECD Guideline No. 406 and EPA OPPTS 870.2600 (Skin Sensitisation)

Method

The dermal sensitization potential of the test material was evaluated in Hartley-derived albino guinea pigs. Ten male and 10 female guinea pigs were topically treated with 100% (as received) the test material once per week, for 3 consecutive weeks. Following a 2-week rest period, a challenge was performed whereby the 20 test and 10 previously untreated (naïve) challenge control guinea pigs were topically treated with 100% the test material as received. Challenge responses in the test animals were similar to those of the challenge control animals.

An α-Hexylcinnamaldehyde (HCA) positive control group consisting of 10 HCA test and 10 HCA control guinea pigs was included in this study. The animals were treated as above with the HCA test animals receiving 5% w/v HCA in ethanol for induction and 2.5% and 1.0% w/v HCA in acetone for challenge.

Results

Following challenge with 100% (as received) of the test material, dermal reactions were limited to scores of 0 and ± in test and challenge control animals. Group mean dermal scores were similar in the test and challenge control animals.

Following challenge with 2.5% w/v HCA in acetone, dermal scores of 1 or 2 were noted in 10/10 HCA test animals at the 24-hour and 48-hour scoring intervals. Dermal reactions in the HCA control animals were limited to scores of 0. Group mean dermal scores were higher in the HCA test animals compared to the HCA control animals.

Following challenge with 1.0% w/v HCA in acetone, dermal scores of 1 or 2 were noted in 9/10 HCA test animals at the 24-hour scoring interval, and in 8/10 test animals at the 48-hour scoring interval. Dermal reactions in the HCA control animals were limited to scores of 0. Group mean dermal scores were higher in the HCA test animals compared to the HCA control animals.

Conclusion

Based on the results of this study, the test material is not considered to be a contact sensitizer in guinea pigs, as the criterion for sensitization (dermal scores ≥ 1 in at least 15% of the test animals) was not met. The results of the HCA positive control study demonstrated that a valid test was performed and indicated that the test design would detect potential contact sensitizers.