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Diss Factsheets
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EC number: 222-389-8 | CAS number: 3457-61-2
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
![](https://echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_toxicological-information.png)
Endpoint summary
Administrative data
Description of key information
GPMT assay
The delayed contact hypersensivity of Proximon 801 (96.8% tert-buty-cumyl peroxide) was evaluated in Guinea pigs according to OECD N°406 guideline (Magnusson and Kligman test). The induction phase has been realized both by intradermal route on day 1 (10 % in vehicle) and by cutaneous route on day 8 (undiluted) in 2 groups of guinea pigs: 5 males and 5 females for control group and 10 males and 10 females for treated group. The challenge phase was realized on day 22 by cutaneous application of the undiluted test material on one flank (vehicle on the other flank); the cutaneous reactions were scored 24 and 48 hours after the challenge phase.
No cutaneous reactions were observed in the animals of the control group. In the treated group, at the 24-hour reading, a very slight or well-defined erythema (grade 1 or 2) was noted in 6/20 and 1/20 animals, respectively. At the 48-hour reading, a very slight erythema (grade 1) persisted in 5/20 animals and dryness of the skin was recorded in 3/20 animals. The slight cutaneous reactions observed at the 24-hour reading and which persisted at the 48-hour reading are most probably attributable to a weak sensitizing potential of the test substance. Peroximon 801 induced delayed contact hyper sensitivity in 5/20 (25%) guinea-pigs. Nevertheless, a classification is not warranted since only 25 % of animals were supposed sensitized and since topical application was done with the undiluted substance. In conclusion, the test item is not considered as sensitizing in guinea pigs.
QSAR models
This conclusion was supported by the negative results for allergic contact dermatitis in 3 QSAR models.
The allergic contact dermatitis potential of tert-butyl 1-methyl-1-phenylethyl peroxide in guinea pig and human was evaluated via the Danish QSAR database using MultiCASE Ultra, Leadscope Enterprise and SciMatics SciQSAR versions of commercial CASE Ultra model A33. No indication of skin sensitisation was reported, tert-butyl 1-methyl-1-phenylethyl peroxide being inside the applicability domain of 2/3 models.
The presence of structural alert in the molecular structure of tert-butyl 1-methyl-1-phenylethyl peroxide was evaluated with Toxtree (Version 2.5.0). The alerts for skin sensitization capture electrophilic mechanistic information and include “Michael-type addition reaction”, “Schiff base formation”,“acylation”, “nucleophilic aromatic substitution” (SNAr) and “second order nucleophilic aliphatic substitution” (SN2). The final alert “Reactivity domain alert” is true if any other alert is true. No skin sensitisation reactivity domains alerts were identified.
The Pred-Skin app allows to make predictions using externally validated QSAR models for skin sensitization based on murine (LLNA) and human data. Tert-butyl 1-methyl-1-phenylethyl peroxide was predicted to be non-sensitizer in the LLNA with a high probability (70 or 90%).
Key value for chemical safety assessment
Skin sensitisation
Link to relevant study records
- Endpoint:
- skin sensitisation: in vivo (non-LLNA)
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 1999
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: GLP guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 406 (Skin Sensitisation)
- GLP compliance:
- yes (incl. QA statement)
- Type of study:
- guinea pig maximisation test
- Justification for non-LLNA method:
- The study was performed before the implementation of the REACH regulation.
- Species:
- guinea pig
- Strain:
- Dunkin-Hartley
- Sex:
- male/female
- Details on test animals and environmental conditions:
- Environmental conditions
. temperature: 21 ± 2°C
. relative humidity: 30 to 70%
. light/dark cycle: 12 h/12 h
. ventilation: approximately 12 cycles/hour of filtered, non-recycled air.
The temperature and relative humidity were under continuous control and recording. The records were checked daily and filed. In addition to these daily checks, the housing conditions and corresponding instrumentation and equipment are verified and calibrated at regular intervals.
During the acclimatization period and throughout the study, the animals were housed individually in polycarbonate cages (48 cm x 27 cm x 20 cm) equipped with a polypropylene bottle. Dust-free sawdust was provided as litter (SICSA, 92142 Alfortville, France).
Bacteriological and chemical analyses of the sawdust, including the detection of possible contaminants (pesticides, heavy metals), are perfonned regularly by external laboratories. The results of these analyses are archived at CIT.
-Food and water ad libitum
Animals: - Route:
- intradermal
- Vehicle:
- corn oil
- Concentration / amount:
- 10%
- Day(s)/duration:
- Day 1
- Adequacy of induction:
- highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
- Route:
- epicutaneous, occlusive
- Vehicle:
- unchanged (no vehicle)
- Concentration / amount:
- 100%
- Day(s)/duration:
- Day 8
- Adequacy of induction:
- non-irritant substance, but skin pre-treated with 10% SDS
- Route:
- epicutaneous, occlusive
- Vehicle:
- unchanged (no vehicle)
- Concentration / amount:
- 100%
- Day(s)/duration:
- Day 22
- Adequacy of challenge:
- highest non-irritant concentration
- No. of animals per dose:
- treated group: 10 males and 10 female
control group: 5 males and 5 females - Details on study design:
- RANGE FINDING TESTS:
Intradermal test: In the two animals (both sexes), concentration of the substance at 75 %, 50 % and 25 % (with or without FCA) caused necrosis and severe oedema at 24 and 48 hours, no effects after 6 days.
At 10 %, 5 % and 1 % with FCA caused irritation at 24, 48 hours and 6 days (both sexes)
At 10 %, 5 % and 1 % without FCA caused irritation at 24, 48 hours and slight irritation at 6 days (both sexes)
Cutaneous test:In two animals, topical adminitration caused no irritation, neither 100 % neor 50 %.
MAIN STUDY
A. INDUCTION EXPOSURE
* Intradermal induction:
- On day 1, 3 injections are realized on the scapular area:
- 0.1mL of Freund's complete adjuvant at 50 % in 0.9% NaCl
- 0.1mL of the test item at (10) % (for treated group) or 0.1mL of vehicle (for control group)
- 0.1mL of a mixture 50/50 (V/V) of Freund's complete adjuvant in 0.9% NaCl and the test item at (10 ) % (for treated group) or the vehicle (for control group).
* Cutaneous induction:
- On day 7, local irritation is induced by application of Sodium Laurylsulfate 10% in Vaseline
- On day 8, occlusive application on the scapular area of 0.5mL of the undiluted test item (for treated group) or vehicle (for control group) for 48 hours
B. CHALLENGE EXPOSURE D22
On day 22, 24hours occlusive application on the scapular area of 0.5mL of the undiluted test item 10% on the right flank and 0.5mL of the vehicle on the left flank.
Reactions are evaluated 24 and 48 hours after removal of the dressing - Challenge controls:
- There were no challenge controls
- Positive control substance(s):
- yes
- Remarks:
- 2,4-Dinitrochlorobenzene
- Positive control results:
- Valid, with DNCB
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- test chemical
- Dose level:
- 0.5 ml undiluted
- No. with + reactions:
- 7
- Total no. in group:
- 20
- Clinical observations:
- only erythema was observed (6 animals with a score of 1, one animal with a score of 2)
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- test chemical
- Dose level:
- 0.5 ml undiluted
- No. with + reactions:
- 5
- Total no. in group:
- 20
- Clinical observations:
- only erythema was observed (3 animals with a score of 1 with dryness of the skin, 2 animals with a score of 2)
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- negative control
- Dose level:
- 0.5 ml undiluted
- No. with + reactions:
- 0
- Total no. in group:
- 10
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- negative control
- Dose level:
- 0.5 ml undiluted
- No. with + reactions:
- 0
- Total no. in group:
- 10
- Interpretation of results:
- GHS criteria not met
- Conclusions:
- Peroximon 801 induced delayed contact hyper sensitivity in 5/20 (25%) guinea-pigs but as the skin reactions are slight a classification is not warranted.
- Executive summary:
The delayed contact hypersensivity of Peroximon 801 (96.8% tert-buty-cumyl peroxide) was evaluated in Guinea pigs according to OECD N°406 guideline (Magnusson and Kligman test). The induction phase has been realized both by intradermal route on day 1 (10 % in vehicle) and by cutaneous route on day 8 (undiluted) in 2 groups of guinea pigs: 5 males and 5 females for control group and 10 males and 10 females for treated group. The challenge phase was realized on day 22 by cutaneous application of the undiluted test material on one flank (vehicle on the other flank); the cutaneous reactions were scored 24 and 48 hours after the challenge phase.
No cutaneous reactions were observed in the animals of the control group. ln the treated group, at the 24-hour reading, a very slight or well-defined erythema (grade 1 or 2) was noted in 6/20 and 1/20 animals, respectively. At the 48-hour reading, a very slight erythema (grade 1) persisted in 5/20 animals and dryness of the skin was recorded in 3/20 animals. The sligh cutaneous reactions observed at the 24-hour reading and which persisted at the 48-hour reading are most probably attributable to a weak sensitizing potential of the test substance. Paroximon 801 induced delayed contact hyper sensitivity in 5/20 (25%) guinea-pigs. Nevertheless, a classification is not warranted since only 25 % of animals were supposed sensitized and since topical application was done with the undiluted substance.
- Endpoint:
- skin sensitisation: in vitro
- Data waiving:
- study scientifically not necessary / other information available
- Justification for data waiving:
- an in vitro skin sensitisation study does not need to be conducted because adequate data from an in vivo skin sensitisation study are available
Referenceopen allclose all
Individual scoring:
Group |
Sex |
Animal |
24h |
48h |
||||||
Erythema |
Oedema |
Erythema |
Oedema |
|||||||
LF |
RF |
LF |
RF |
LF |
RF |
LF |
RF |
|||
Control |
M |
31 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
32 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
33 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
34 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
35 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
|
||||||||||
Control |
F |
46 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
47 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
48 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
49 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
50 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
|
||||||||||
Treated |
M |
36 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
37 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
38 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
39 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
40 |
0 |
1 |
0 |
0 |
0 |
1/S |
0 |
0 |
||
41 |
0 |
2 |
0 |
0 |
0 |
1/S |
0 |
0 |
||
42 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
43 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
||
44 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
45 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
|
||||||||||
Treated |
F |
51 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
52 |
0 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
||
53 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
54 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
55 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
56 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
||
57 |
0 |
1 |
0 |
0 |
0 |
1/S |
0 |
0 |
||
58 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
59 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
60 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
LF=left flank
RF=right flank
A=crusts
S=dryness of the skin
no visible change.............................................................................................0
discrete or patchy erythema.............................................................................1
moderate and confluent erythema.....................................................................2
intense erythema..............................................................................................3
No cutaneous reactions were observed in the animals of the control group.
ln the treated group, at the 24-hour reading, a very slight or well-defined erythema (grade 1 or 2) was noted in 6/20 and 1/20 animals, respectively.
At the 48-hour reading, a very slight erythema (grade 1) persisted in 5/20 animals and dryness of the skin was recorded in 3/20 animals.
The slight cutaneous reactions observed at the 24-hour reading and which persisted at the 48-hour reading are most probably attributable to a weak sensitizing potential of the test substance.
Positive controls were also run per standard protocol. The positive control, DNCB resulted in 90% of guinea pigs showing positive reaction in the GPMT (Study Report).
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not sensitising)
Respiratory sensitisation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Justification for classification or non-classification
According to EU Regulation (EC) N0. 1272/2008 (CLP), Tert-butyl-a,a-dimethylbenzyl peroxide (TBCP) is not classified for skin sensitisation.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
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