1,3,5-tris[[4-tert-butyl-3-hydroxy-2,6-xylyl]methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione

Endpoint summary

Description of key information

In studies conducted in humans and rabbits, the test material produced no skin irritation. Minimal and fully reversible effects in the eyes of rabbits were reported.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1976

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Older, reasonably well-conducted study for the period, but no GLP or guideline followed. Scoring system was not described.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

No current guideline followed; the modified Draize-Shelanski Repeat Insult Patch Test was conducted.

GLP compliance:

no

Species:

human

Details on test animals or test system and environmental conditions:

One hundred healthy adults (61 females, 39 males, 18-50 years of age, 58 black, 2 Puerto Rican, 40 white) served as subjects for the study

Type of coverage:

semiocclusive

Preparation of test site:

other: No details on test site preparation

Vehicle:

other: white petrolatum

Controls:

no

Amount / concentration applied:

2.5 %

Duration of treatment / exposure:

24 hours

Observation period:

On removal of the patch to 24 hours thereafter.

Number of animals:

100 adult human beings

Details on study design:

A 15 mm patch of test material (2.5% in white petrolatum) was applied to patch sites on the backs or volar forearms of the subjects for 10 alternate-day 24 hour periods under occlusion. Following a seven day test period (in which subjects were evaluated daily), 15 mm challenge patches (1.0% in white petrolatum) were applied in the same manner to fresh sites on the backs or volar forearms of all subjects for 24 hours. Challenge sites were read on removal of the patch and 24 hours thereafter.

Irritation parameter:

overall irritation score

Basis:

other: score range

Time point:

other: 1-10 days after induction and at 24 and 48 hr after challenge

Score:

0

Remarks on result:

other: all subjects had scores of 0

Irritant / corrosive response data:

All subjects had scores of 0 at 1-10 days after induction and 24 and 48 hours after challenge. The material was therefore neither irritating nor sensitizing.

Interpretation of results:

GHS criteria not met

Conclusions:

There were no instances of irritation or sensitization from this material on the Draize-Shelanski Test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not 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:

April - June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Also according to GLP

Justification for type of information:

Until 2016, Annex IX of REACH required an in vivo test for eye irritation to confirm negative results of in vitro tests. In the interest of animal welfare and to minimize any testing likely to produce severe responses in animals, a weight of evidence analysis was performed, prior to the start of this in vivo eye irritation study in the rabbit. As recommended in the test guidelines, all available information was evaluated (e.g. existing human and animal data, literature, substance data, analysis of structure-activity relationships, physicochemical properties and reactivity (pH, buffering capacity) and in vitro, ex-vivo and in vivo tests) to determine the need for in vivo eye testing.
Because no skin effects were noted in the in vivo skin irritation study and since a negative result was anticipated for the possible in vitro study, it was concluded that there is a need to perform this in vivo eye irritation study in rabbit in order to establish the possible eye irritating properties of the test substance.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Kisslegg, Germany
- Age at study initiation: at least 6 weeks old
- Weight at study initiation: at least 1 kg
- Housing: cages with perforated floors and shelters
- Diet: ca. 100 g per day of pelleted diet for rabbits (Global Diet 2030 from Harlan Teklad®, Mucedola, Milanese, Italy). Hay and wooden sticks were available during the study period
- Water: free access to tap water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-24
- Humidity (%): 40-70
- Air changes (per hr): ca. 15
- Photoperiod (hrs dark / hrs light): 12/12

Vehicle:

unchanged (no vehicle)

Controls:

other: one eye remained untreated and served as reference control

Amount / concentration applied:

TEST MATERIAL
Amount applied: 74 mg (= approx. 0.1 ml)

Duration of treatment / exposure:

single instillation

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

3 males

Details on study design:

STUDY DESIGN
The study was performed in a stepwise manner and was started by treatment of a single rabbit (sentinel). The two other animals were treated in a similar manner three weeks later, after considering the degree of eye irritation observed in the first animal.

TREATMENT
Animals were treated by instillation of, on average, 74.0 mg (range 73.9 - 74.2 mg) of the test substance (a volume of approximately 0.1 mL) in the conjunctival sac of one of the eyes after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second to prevent loss of the test substance.

REMOVAL OF TEST SUBSTANCE
-Washing (if done): No

OBSERVATIONS
- Mortality/Viability: Twice daily.
- Toxicity: At least once daily.
- Body Weight: Day of treatment (prior to instillation) and after the final observation.
- Necropsy: No necropsy was performed according to protocol.
- Irritation: The eyes of each animal were examined approximately 1, 24, 48 and 72 hours and 7 days after instillation of the test substance. The irritation scores and a description of all other (local) effects were recorded.The irritation was assessed according to OECD 405.

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 48h

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.3

Reversibility:

fully reversible within: 7d

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1.3

Reversibility:

fully reversible within: 7d

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 48h

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 48h

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Irritant / corrosive response data:

Effects on cornea, iris and conjunctivae were observed:
The corneal injury consisted of slight dulling of the normal lustre on Day 1 and no epithelial damage was noted. Iridial irritation grade 1 was observed and resolved within 24 hours in two animals and within 48 hours in one animal. The irritation of the conjunctivae consisted of redness, chemosis and discharge and completely resolved within 48 hours in one animal and within 7 days in the other two animals.

Other effects:

No staining of ocular tissues by the test substance was oberved. Remnants of the test substance were present in the eye and on the outside of the eyelids in all three animals at 1 hour after exposure.
No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the above results, the test substance does not have to be classified and has no obligatory labelling requirement for eye irritation.

Executive summary:

An eye irritation study was performed according to OECD TG 405 and under GLP conditions. An instillation of 74 mg of the test item in one eye of 3 rabbits. One eye remained untreated and served as a control. No irreversible effects were noted.

Based on the results above, the test material is not classified for eye irritation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin

A group of 100 human volunteers (61 females, 39 males, 18-50 years of age) were treated under semi-occlusive wrap with a 2.5% concentration of the test substance in white petrolatum as part of a modified Draize-Shelanski Repeat Insult Patch Test. Exposures were for 24 h on the backs or forearms of all subjects. Test material was applied on 10 alternate days and after a 7 day rest, challenge patches with 1% test material in white petrolatum were administered for 24 h. There was no irritation reported in any subjects with all irritation scores of 0.

In a primary skin irritation study in rabbits conducted according to OECD Guideline 404, the test substance (0.5 g) moistened with 0.6 mL of water was applied under semi-occlusive wrap the shaved skin of 3 male test animals. The exposure was for 4 h with a 72-h observation period. Under the test conditions, there was no systemic toxicity or skin irritation.

Eye

In an older range-finding study, the eye irritancy of the test material was determined in a rabbits in a modified FHSA procedure. A 100 mg portion of the test material was placed into the rabbit eyes (without washing) and eyes evaluated at 24, 48 and 72 h. The material was not irritating.

In an acute eye irritation/corrosion study in 3 male New Zealand white rabbits conducted according to OECD Guideline 405, approximately 0.1 mL (74 mg) of test material was placed into the eyes of the rabbits and effects observed for 7 days. The corneal effects reported consisted of slight dulling on Day 1 but with no epithelial damage. An iris irritation grade of 1 was observed and resolved within 24 hours in two animals and within 48 hours in one animal. The irritation of the conjunctivae consisted of redness, chemosis and discharge, and these effects completely resolved within 48 hours in one animal and within 7 days in the other two animals. The results indicate only minimal eye irritation potential.

In an acute dermal toxicity study conducted in rabbits, there was no signs of intoxication or any clinical effects noted up to limit dose of 5000 mg/kg bw. In an acute dermal toxicity study conducted in rats at 2000 mg/kg bw, white staining of the skin was seen in all animals on Day 2 and one female showed scaling of the skin between Days 4 and 11. However, no macroscopic abnormalities were present at necropsy.

Justification for selection of skin irritation / corrosion endpoint:
The test material was not irritating in a human HRIPT studies with 100 volunteers

Justification for selection of eye irritation endpoint:
In an OECD 405 (Acute Eye Irritation/Corrosion) study in rabbits, the test material produced no corneal effects and only minimal and fully reversible effects on the iris, conjunctivae and on chemosis

Justification for classification or non-classification

In well-conducted skin irritation in humans and rabbits, there was no significant skin irritation noted. In a well conducted studies in rabbits, there were only minimal eye effects that were fully reversible. Thus, no classification is warranted.