Saccharomyces cerevisiae cell wall, extracted

Endpoint summary

Description of key information

Based on the results of the two available in vivo key studies (Richeux, OECD TG 404, GLP, 2011, Klimisch 1; Richeux, OECD TG 405, GLP, 2011, Klimisch 1), the test substance Saccharomyces cerevisiae cell walls, extracted was not classified for skin and eye irritation according to the CLP criteria.

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:

From 09 June 2011 to 19 December 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

24 April 2002

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Elevage de Gerome (Quartier Labaste­ F40260 Linxe)
- Age at study initiation: 13 weeks old
- Weight at study initiation: 2.45 - 3.10 kg
- Housing: Each animal was kept in an individual box installed in conventional air conditioned animal husbanding.
- Diet (e.g. ad libitum): foodstuff (SDS - C15) ad libitum
- Water (e.g. ad libitum): tap-water from public distribution system ad libitum
Microbiological and chemical analyses of the water were carried out once evety six months by IPL, Sante, Environnement Durables - Atlantique
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23
- Humidity (%): 30 to 70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 / 12 (continuous light (07.00 to 19.00))

IN-LIFE DATES: not specified.

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

other: on the opposite flank an untreated area served as the control.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g
- Concentration (if solution): not applicable

Duration of treatment / exposure:

4h (as no tissue destruction was noted after a treatment during 3 minutes and 1 hour, the test item was applied, during 4 h).

Observation period:

1 h and then 24, 48 and 72 h after removal of the patch and up to 14 days if necessary (if no reaction is observed 72 h after the treatment, the study is terminated. In case of persistent reactions, additional observations can be carried out from day 4 to day 14 in order to determine the reversible character of the lesions observed).

Number of animals:

3 male rabbits (initially, a single animal was treated. After consideration of the cutaneous responses produced in the first treated animal on day 3, two additional animals were treated during 4 h).

Details on study design:

TEST SITE
- Area of exposure: 6 cm2
- % coverage: not specified
- Type of wrap if used: the treated area is covered with a gauze patch, which is maintained in position by a semi occlusive dressing. The dressing is covered with an elastic strap taped in place around the animal's body, taking care not to impede its respiratory and abdominal movements.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes; after the removal of the patch, the treated area was rinsed with distilled water.
- Time after start of exposure: after the removal of the patch (4h post treatment).

OBSERVATION TIME POINTS
(indicate if minutes, hours or days)
1 h and then 24, 48 and 72 h after removal of the patch.

SCORING SYSTEM:
- Method of calculation: 1h then 24, 48 and 72 h after patch removal the animals underwent a macroscopic skin examination, on each occasion under the same conditions (in particular with regard to ambient lighting). This examination consisted in assessing the irritant reactions in the treated zone, compared to a control area. The following scales are used:

Erythema and Eschar formation
0 ...... No etythema
I ...... Very slight Eythcma (barely perceptible)
2 ...... Well defined erythema
3 ...... Moderate to severe erythema
4 ...... Severe erythema (beef redness) with eschars formation preventing grading of erythema

Oedema
0 .......No oedema
I..........Very slight oedema (barely perceptible)
2 ....... Slight oedema (contour clearly defined)
3 ....... Moderate oedema (raised approx. 1 mm)
4 ....... Severe oedema (raised more than 1 mm, and extending beyond area of exposure)

EXAMINATION OF THE GENERAL CONDITION OF THE ANIMALS
The systemic toxicity, expressing by behavioral abnormalities, alteration of neuro-vegetative reactions or decrease feeding, and any toxic effects are to be logged and described. The animals are weighed at the start and at the end of the test.

Irritation parameter:

erythema score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

erythema score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

erythema score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Reversibility:

fully reversible within: 48h

Irritation parameter:

edema score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

edema score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

edema score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritant / corrosive response data:

No skin reaction was recorded in any animal 1h after the patch removal.
A slight erythema was noted on the treated area of one animal, 24 h after the patch removal. The reaction was totally reversible at the reading time 48 hours.

Other effects:

- Other adverse local effects: none.
- Other adverse systemic effects: none.

Animal weight evolution:

Animal #	Weight at start of experiment (kg)	Weight at end of experiment (kg)
1	2.45	2.55
2	2.93	3.10
3	2.89	3.00

Interpretation of results:

GHS criteria not met

Conclusions:

Under the experimental conditions of this study, the test item Saccharomyces cerevisiae cell wall, extracted was not irritating to the rabbit skin. Thus, the test material is not classified for skin irritation / corrosion according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging (CLP) criteria and the UN-GSH system.

Executive summary:

This GLP-compliant study was performed to assess the potential of Saccharomyces cerevisiae cell wall, extracted to induce skin irritation in vivo, according to OECD Guideline 404 (Acute Dermal Irritation/Corrosion) and EU method B.4 (EU Acute Toxicity: Dermal Irritation / Corrosion).

Material and methods

0.5 g of test item was applied to the skin of three New Zealand White rabbits. The test item was applied as a single dose. Sufficient water was used to dampen the test material to ensure good contact with the skin. The treated area is covered with a  gauze patch, which is maintained in  position by a semi occlusive dressing. The dressing is covered with an elastic strap taped in place around the animal's body, taking care not to impede its respiratory and abdominal movements. Each rabbit is its own control, i.e untreated skin areas of the test animal serve as the control. After 4h, the remaining test item was removed with distilled water.

Systemic toxicity, expressing by behavioral abnormalities, alteration of neuro-vegetative reactions or decrease feeding, and any toxic effects were logged and described. The animals are weighed at the start and at the end of the test. The irritancy of the test item was evaluated according to the Draize method. Animals were examined at 1, 24, 48, and 72 hours after the patch removal.

Results

There was no mortality during the observation period and no test item related effect on body weight.

No skin reaction was recorded in any animal 1h after the patch removal.

A slight erythema was noted on the treated area of one animal, 24 h after the patch removal. The reaction was totally reversible at the reading time 48 hours.

The animals’ individual mean scores (24, 48 and 72 hours after patch removal) for erythema were 0.00, 0.00 and 0.33 respectively.

The animals’ individual mean scores (24, 48 and 72 hours after patch removal) for oedema were 0.00, 0.00 and 0.00 respectively.

Conclusion

Under the experimental conditions of this study, the test item Saccharomyces cerevisiae cell wall, extracted was not irritating to the rabbit skin. Thus, the test material is not classified for skin irritation / corrosion according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging (CLP) criteria and the UN-GSH system.

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:

From 09 May 2011 to 19 December 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

24 April 2002

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Elevage de Gerome (Quartier Labaste­ F40260 Linxe)
- Age at study initiation: 13 weeks old
- Weight at study initiation: 2.66 - 3.15 kg
- Housing: Each animal was kept in an individual box installed in conventional air conditioned animal husbanding.
- Diet (e.g. ad libitum): foodstuff (SDS - C15) ad libitum
- Water (e.g. ad libitum): tap-water from public distribution system ad libitum
Microbiological and chemical analyses of the water were carried out once evety six months by IPL, Sante, Environnement Durables - Atlantique
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23
- Humidity (%): 30 to 70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 / 12 (continuous light (07.00 to 19.00))

IN-LIFE DATES: not specified.

Vehicle:

unchanged (no vehicle)

Controls:

other: the other eye remained untreated serving as control.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 g
- Concentration (if solution): not applicable

Duration of treatment / exposure:

0.1 g of the test item was instilled into the conjunctival sac of one eye after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second in order to prevent loss of the test item. The other eye remained untreated serving as control.

Observation period (in vivo):

Ocular examinations were performed on both right and left eyes 1h, 24, 48 and 72 hours following treatment. If no reaction is observed 72 hours after instillation, the study is terminated. In case of persistent reactions, additional observations can be carried out from day 4 to day 21 in order to determine the reversible character of the lesions observed.

Number of animals or in vitro replicates:

3 female rabbits (initially, a single animal was treated. After consideration of the responses produced on day 1, two additional animals were treated).

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no
- Time after start of exposure: not applicable.

SCORING SYSTEM:
Eye examinations were carried out using the scale of lesion scores in the following order:

CHEMOSIS (A)
No swelling ....................................................................................................................................0
Slight swelling, including the nictitating membrane...................................................................... 1
Swelling with eversion of the eyelid..............................................................................................2
Swelling with eyelid half-closed....................................................................................................3
Swelling with eyelid more than half-closed...................................................................................4


DISCHARGE (B)
No discharge.................................................................................................................................0
Slight discharge (normal slight secretions in the inner corner not to be taken into account)........1
Discharge with moistening of the eyelids and neighbouring hairs...............................................2
Discharge with moistening of the eyelids and large areas around the eye..................................3


REDNESS (C)
Blood vessels normal....................................................................................................................0
Vessels significantly more prominent than normal......................................................................1
Vessels individually distinguishable with difficulty:
Generalised red coloration..........................................................................................................2
Generalised deep red coloration.................................................................................................3


IRIS (D)
Normal ...........................................................................................................................................0
Iris significantly more wrinkled than normal, congestion,
swelling of the iris which continues to react to light, even slowly................................................1
No reaction to light, haemorrhage, significant damage (any or all of these characteristics)........2


CORNEA: DEGREE OF OPACITY (E)
No modification visible either directly or after instillation of fluorescein (no loss of glint or polish)...0
Translucent areas (diffuse or disseminated), iris details clearly visible ...........................................1
Easily identifiable translucent area, iris details slightly obscured......................................................2
Opalescent area, no iris details visible, pupil outline scarcely distinguishable...................................3
Total corneal opacity, completely obscuring the iris and pupil............................................................4


CORNEA: EXTENT OF OPACITY (F)
Opaque area present but covering one quarter or less.................................................................... 1
Between one quarter and half......................................................................................................... 2
Between half and three quarters........................................................................................................3
Between three quarters and the entire surface................................................................................ 4


TOOL USED TO ASSESS SCORE: Examination of reactions can be facilitated by use of a binocular loupe, hand slit-lamp, biomicroscope, or other suitable device. After recording the observations at 24 h, the eyes may be further examined with the aid of fluorescein.

Irritation parameter:

cornea opacity score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

cornea opacity score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

iris score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

iris score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

iris score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.67

Reversibility:

fully reversible within: 72h

Irritation parameter:

conjunctivae score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.33

Reversibility:

fully reversible within: 48h

Irritation parameter:

conjunctivae score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Reversibility:

fully reversible within: day 7

Irritation parameter:

chemosis score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

chemosis score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Reversibility:

other: not applicable

Irritation parameter:

chemosis score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.67

Reversibility:

fully reversible within: 72h

Irritant / corrosive response data:

The ocular reactions observed during the study have been slight to moderate and totally reversible in the three animals (results of individual and mean scores are presented in Table 1 in "any other information on results incl. tables" section):
- at the conjunctivae level: a slight to moderate redness noted 1h after the test item instillation and totally reversible between days 2 and 7, associated with a slight chemosis noted 1h after the test item instillation and totally reversible between days 1 and 3;
- at the cornea level: a slight opacity, noted in one animal 1h after the test item instillation and completely resolved 24 h post exposure.

Other effects:

- Lesions and clinical observations: none
- Ophthalmoscopic findings: none
- Histopathological findings: not performed
- Effects of rinsing or washing: not applicable
- Other observations: none

Table 1.Individual and mean scores for Conjunctivae, Iris and Cornea

Animal #	Time after treatment	Conjunctivae		Iris	Cornea
		Chemosis (A)	Redness (C)	Lesion (D)	Opacity (E)
1	24h	0	1	0	0
	48h	0	1	0	0
	72h	0	0	0	0
Mean		0.0	0.67	0.0	0.0
2	24h	0	1	0	0
	48h	0	0	0	0
	72h	0	0	0	0
Mean		0.0	0.33	0.0	0.0
3	24h	1	3	0	0
	48h	1	2	0	0
	72h	0	1	0	0
	7 days	0	0	0	0
Mean (24-48-72h)		0.67	2.0	0.0	0.0

 

Interpretation of results:

GHS criteria not met

Conclusions:

Under the experimental conditions of this study, the test item Saccharomyces cerevisiae cell wall, extracted was not irritating to the rabbit eyes. Thus, the test material is not classified for eye irritation / corrosion according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging (CLP) criteria and the UN-GSH system.

Executive summary:

This GLP-compliant study was performed to assess the potential of Saccharomyces cerevisiae cell wall, extracted to induce eye irritation in vivo, according to OECD Guideline 405 (Acute Eyeal Irritation/Corrosion) and EU method B.5 (Acute Toxicity: Eyel Irritation / Corrosion).

Material and methods

0.1 g of test item were instilled, as supplied, into the conjunctival sac of one eye of each of the three New Zealand White rabbits. The test item was applied as a single dose. The lids were gently held together for about one second. The other eye remained untreated and served as control. No washing was performed.

The degree of eye irritation/corrosion is evaluated by scoring lesions of conjunctivae, cornea and iris on both right and left eyes 1h, 24, 48 and 72 hours following treatment. If no reaction is observed 72 hours after instillation, the study is terminated. In case of persistent reactions, additional observations can be carried out from day 4 to day 21 in order to determine the reversible character of the lesions observed. Other effects in the eye and adverse systemic effects are also described.

Results

There was no mortality during the observation period.

The ocular reactions observed during the study have been slight to moderate and totally reversible in the three animals:

- at the conjunctivae level: a slight to moderate redness noted 1h after the test item instillation and totally reversible between days 2 and 7, associated with a slight chemosis noted 1h after the test item instillation and totally reversible between days 1 and 3;

- at the cornea level: a slight opacity, noted in one animal 1h after the test item instillation and completely resolved 24 h post exposure.

The animals’ individual mean scores (24, 48 and 72 h) for corneal opacity were 0.00, 0.00 and 0.00 respectively.

The animals’ individual mean scores (24, 48 and 72 h) for iris were 0.00, 0.00 and 0.00 respectively.

The animals’ individual mean scores (24, 48 and 72 h) for conjunctivae were 0.67, 0.33 and 2.00 respectively.

The animals’ individual mean scores (24, 48 and 72 h) for chemosis were 0.00, 0.00 and 0.67 respectively.

Conclusion

Under the experimental conditions of this study, the test item Saccharomyces cerevisiae cell wall, extracted was not irritating to the rabbit eyes. Thus, the test material is not classified for eye irritation / corrosion according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging (CLP) criteria and the UN-GSH system.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Two key studies were available for skin and eye irritation evaluation:

An in vivo GLP compliant skin irritation test of Saccharomyces cerevisiae cell walls, extracted was performed in three New Zealand White rabbits (Richeux, OECD TG 404, GLP, 2011, Klimisch 1). The test item was applied as a single dose of 0.5g under semi-occlusive dressing. After 4h, the remaining test item was removed with distilled water. The irritancy of the test item was evaluated according to the Draize method. Animals were examined at 1h, 24-, 48- and 72-hours after the patch removal.

There was no mortality during the observation period and no test item related effect on body weight. No skin reaction was recorded in any animal 1h after the patch removal. A slight erythema was noted on the treated area of one animal, 24 h after the patch removal. The reaction was totally reversible at the reading time 48 hours. The animals’ individual mean scores (24, 48 and 72 hours after patch removal) for erythema were 0.00, 0.00 and 0.33 respectively. The animals’ individual mean scores (24, 48 and 72 hours after patch removal) for oedema were 0.00, 0.00 and 0.00 respectively. In conclusion, under the experimental conditions of the study, the results indicate that the test item is non-irritant to skin.

An in vivo GLP compliant eye irritation test of Saccharomyces cerevisiae cell walls, extracted was performed in New Zealand White rabbits (Richeux, OECD TG 405, GLP, 2011, Klimisch 1). The test item was applied as a single dose of 0.1g into the conjunctival sac of one eye of each of the three New Zealand White rabbits. The degree of eye irritation/corrosion was evaluated by scoring lesions of conjunctivae, cornea and iris on both right and left eyes 1h, 24, 48 and 72 hours following treatment. If no reaction is observed 72 hours after instillation, the study is terminated. In case of persistent reactions, additional observations can be carried out from day 4 to day 21 in order to determine the reversible character of the lesions observed.

There was no mortality during the observation period. The ocular reactions observed during the study have been slight to moderate and totally reversible in the three animals:

- at the conjunctivae level: a slight to moderate redness noted 1h after the test item instillation and totally reversible between days 2 and 7, associated with a slight chemosis noted 1h after the test item instillation and totally reversible between days 1 and 3;

- at the cornea level: a slight opacity, noted in one animal 1h after the test item instillation and completely resolved 24 h post exposure.

The animals’ individual mean scores (24, 48 and 72 h) for corneal opacity were 0.00, 0.00 and 0.00 respectively. The animals’ individual mean scores (24, 48 and 72 h) for iris were 0.00, 0.00 and 0.00 respectively. The animals’ individual mean scores (24, 48 and 72 h) for conjunctivae were 0.67, 0.33 and 2.00 respectively. The animals’ individual mean scores (24, 48 and 72 h) for chemosis were 0.00, 0.00 and 0.67 respectively. In conclusion, under the experimental conditions of the study, the test substance Saccharomyces cerevisiae cell walls, extracted, did not induce eye irritation or serious eye damage.

Justification for classification or non-classification

Based on the two available key studies (Richeux, OECD TG 404, GLP, 2011, Klimisch 1; Richeux, OECD TG 405, GLP, 2011, Klimisch 1), the test substance Saccharomyces cerevisiae cell walls, extracted did not induce skin irritation in a test performed according to OECD TG 405 and did not induce eye irritation in an OECD TG 405 test. Hence, it can be stated that the test substance Saccharomyces cerevisiae cell walls, extracted does not require classification for skin and eye irritation according to the CLP criteria.