Bis(3,5,5-trimethylhexanoyl) peroxide

Endpoint summary

Description of key information

Skin irritation was assessed in a primary dermal irritation study (TNO, 1976) and an in vitro skin corrosion test according to OECD 431
Eye irritation was assessed similar to OECD 405 (TNO, 1976)

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin corrosion: in vitro / ex vivo

Remarks:

in vitro

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2012-03-20 to 2012-03-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Valid without restriction; GLP guideline study

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Human Skin Model Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

other: reconstituted three-dimensional human skin model EpiDerm (MatTek)

Strain:

other: not applicable

Details on test animals or test system and environmental conditions:

Test system:
The test was carried out with the reconstituted three-dimensional human skin model EpiDermTM (MatTek). It consists of non-cancerous, human-derived epidermal keratinocytes (NHEK) which have been cultutred to form a multi-layered, highly differentiated model of the human epidermis. The NHEK are cultured are cultured on chemically modified, collagen-coated cell culture inserts (Millicell). The test systewm exhibits in vivo like morphological and growth characteristics and consists of organised basal, spinous, granular and cornified layers analogous to those found in vivo.

Type of coverage:

other: not applicable

Preparation of test site:

other: not applicable

Vehicle:

unchanged (no vehicle)

Controls:

other: EpiDerm Tissue was treated with distilled water and 8 N KOH

Amount / concentration applied:

The test item was applied undiluted. 50 µl of the test item were dispensed directly onto the EpiDerm tissue. The test item was spread to match size of the tissue.

Duration of treatment / exposure:

3 minutes and 60 minutes exposure

Observation period:

n.a.

Number of animals:

n.a.

Details on study design:

see "any other information on materials and methods incl. tables"

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 min

Value:

90

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 min

Value:

83

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects:

n.a.

Table1: 3 min Exposure

Name	Negative Control		Test item		Positive control
Tissue	1	2	1	2	1	2
Absolute OD550-Werte	2.080	2.087	1.959	1.787	0.309	0.269
	2.082	2.088	1.962	1.784	0.315	0.271
	2.068	2.061	1.945	1.770	0.312	0.269
Mean OD550	2.077	2.079	1.955	1.780	0.312	0.270
SD	0.008	0.015	0.009	0.009	0.003	0.001
Total mean OD550(mean of two replicate tissues)	2.078*		1.868		0.291
Mean relative tissue viability [%]	100		90		14**
Mean inter tissue viability difference [%]***	0.1		9.4		14.5

* mean OD₅₅₀ ≥ 0.8

** mean relative tissue viability of the 3 min positive control ≤ 30 %

*** inter tissue viability difference ≤ 30 %

Table 2: 60 min Exposure

Name	Negative Control		Test item		Positive control
Tissue	1	2	1	2	1	2
Absolute OD550-Werte	1.955	1.763	1.815	1.454	0.114	0.119
	1.983	1.790	1.692	1.376	0.117	0.129
	2.000	1.782	1.706	1.361	0.115	0.121
Mean OD550	1.979	1.778	1.706	1.361	0.115	0.121
SD	0.023	0.014	0.067	0.050	0.002	0.005
Total mean OD550(mean of two replicate tissues)	1.879*		1.567		0.119
Mean relative tissue viability [%]	100		83		6
Mean inter tissue viability difference [%]***	10.7		21.7		6.4

* mean OD₅₅₀ ≥ 0.8

*** inter tissue viability difference ≤ 30 %

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In this study the test item Peroxan NPO is not considered to be corrosive.

Executive summary:

The potential of the test item to induce skin corrosion was analysed by using the three dimensional human skin model EpiDerm, comprising a reconstructed epidermis with a functional stratum corneum. Peroxan NPO was applied topically to the EpiDerm tissue for 3 min and 60 min, respectively followed by immediate determination of cytotoxic effects via MTT reduction assay.

The test item showed no corrosive potential. The mean relative tissue viability (% negative control) was >= 50% (90%) after 3 min treatment and >= 15% (83%) after 60 min treatment.

The controls confirmed the validity of the study. The mean OD550 of the two negative control tissues was >= 0.8 for each exposure period. The mean relative tissue viability of the positive control was =< (14%) after 3 min treatment. The maximum inter tissue difference of replicate tissues of all dose groups was =< 30 % (0.1%-21.7%).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: comparable to guideline study with acceptable restriction

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

: no clinical observation after 1 h

Principles of method if other than guideline:

The techniques of tests as published by the FDA of the US (Fed. Reg. 28 (119), 5582, 1963) and Draize and Kelley (Drug Cosmet. Industr. 71 (1952) 36) are followed

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Housing: individually
- no hay or other extrageneous material that might enter the eye
- examination of of the eyes before testing

Vehicle:

unchanged (no vehicle)

Remarks:

75% solution in isododecane

Controls:

other: untreated eye served as control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 100 µl
- Concentration (if solution): 75% solution in isododecane

Duration of treatment / exposure:

as long as observation period; the eyes were not washed after treatment

Observation period (in vivo):

observation after 24 h, 48 h and 72 h

Number of animals or in vitro replicates:

6

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no washing

SCORING SYSTEM: FDA scoring scale (equivalent to Draize (1944))

TOOL USED TO ASSESS SCORE: binocular

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #5

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #5

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.6

Max. score:

3

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #4

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #5

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0.3

Max. score:

3

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.6

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.6

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0.6

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #5

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0.6

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Other effects:

no other effects

Table 1: Individual scores awarded to the ocular lesions elicited by Trigonox 36-CD 75

Rabbit number	Cornea		Iris	Conjunctivae
				Redness	Chemosis
After 24 hours
25	1		0	2	2
26	0		0	2	3
27	0		0	1	2
28	0		0	2	2
29	0		0	2	3
30	0		0	1	2
After 48 hours
25	0	0		1	0
26	0	0		1	0
27	0	0		1	0
28	0	0		1	0
29	0	0		1	0
30	0	0		0	0
After 72 hours
25	0	0		0	0
26	0	0		0	0
27	0	0		0	0
28	0	0		0	0
29	0	0		0	0
30	0	0		0	0

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The eye lesions caused by Trigonox 36-CD 75 are below the threshold of classification according to regulation No. 1272/2008.

Executive summary:

In a primary eye irritation study 100 µl of Trigonox 36-CD 75 (Bis(3,5,5 -trimethylhexanoyl)peroxide) was instilled into the everted lower lid of one eye of 6 New Zealand White albino rabbits. The eyes were not washed after instillation. Animals were observed after 24, 48 and 72 hours. Irritation was scored according the FDA scoring scale. The eye lesions were of moderate degree after 24h.and completely reversible within 72h. After 24 hours an average score of 1.67 of conjunctivae redness and an average score 2.3 of conjunctivae chemosis was observed. The mean values of the 24-48-72h readings were below the threshold of classification according to regulation No. 1272/2008 (CLP).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation was assessed in a primary dermal irritation study (TNO, 1976). Severe erythema to slight eschar formation was observed 24 h and 72 h after exposure on intact as well as on abraded skin. Very slight to slight edemas were observed on intact as well on abraded skin after 24 h and 72 h. Because the reversibility of the adverse effects had not been assessed after 14 days the study does not allow to conclude on potentially irreversible effects. Thus, an in vitro skin corrosion test according to OECD 431 was conducted to exclude corrosivity. The test item was found not to be corrosive.

Eye irritation was assessed in a primary eye irritation study (TNO, 1976). Eye lesions were of moderate degree after 24h.and completely reversible within 72h. The mean values of the 24-48-72h readings were below the threshold of classification according to regulation No. 1272/2008 (CLP).

Justification for selection of skin irritation / corrosion endpoint:
OECD guideline study

Justification for selection of eye irritation endpoint:
comparable to guideline study

Effects on skin irritation/corrosion: irritating

Justification for classification or non-classification

The test item is a skin irritant according to CLP, but not corrosive (Skin Irrit 2).

A classification as eye irritant has not been warranted. Conjunctivae effects were observed during the first 48h of the experiment not leading to classification according to regulation No. 1272/2008 (CLP).