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Description of key information

There are no reliable studies available for the assessment of the skin irritation and eye irritation endpoints with the target substance, D-(-)-lactic acid. Therefore, data from a suitable read-across partner, L(+)-lactic acid was used to assess the skin and eye irritation potential of the target substance. In accordance with the harmonized classification of the source substance L(+)-lactic acid, classification as Skin Corr. 1C, H314; Eye. Dam 1, H318 and

supplementary labelling as EUH071 is also warranted for D-(-)-lactic acid.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin irritation: in vivo
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.
Reason / purpose for cross-reference:
read-across source
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 1h
Score:
1
Max. score:
8
Reversibility:
fully reversible within: 24h
Remarks on result:
other: Only observed with 4h exposure
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 24h
Score:
0
Max. score:
8
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 48h
Score:
0
Max. score:
8
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 72h
Score:
0
Max. score:
8
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 1h
Score:
1
Reversibility:
fully reversible within: 24 h
Remarks on result:
other: Only observed with 4h exposure
Irritation parameter:
erythema score
Basis:
mean
Time point:
24 h
Score:
0
Irritation parameter:
erythema score
Basis:
mean
Time point:
48 h
Score:
0
Irritation parameter:
erythema score
Basis:
mean
Time point:
72 h
Score:
0
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 1h
Score:
0
Irritation parameter:
edema score
Basis:
mean
Time point:
24 h
Score:
0
Irritation parameter:
edema score
Basis:
mean
Time point:
48 h
Score:
0
Irritation parameter:
edema score
Basis:
mean
Time point:
72 h
Score:
0
Irritant / corrosive response data:
No irritation was noted in Group l animals at either 3 min or l h exposed sites. In Group 2, where exposure was 4h, very slight erythema was noted in all animals. By 24 h after exposure, skin appeared normal. It is concluded from the test results that Lactic Acid Q88 is not corrosive to guinea pig skin. It is also noted that irritation after 4 h exposure was transient and limited to very mild erythema.
Interpretation of results:
other: not irritating
Conclusions:
Under the given conditions, the test item is not irritating to the skin.
Executive summary:

The corrosivity potential of a test material, Lactic Acid Q88, was investigated by means of a test in guinea pigs. The test was designed to assess irritancy and/or corrosivity by means of topical application of the test material to intact skin under semi occlusive conditions for various exposure times: 3 min, 1h and 4h. Two groups of 3 animals were used. In group 1 exposures of 3 min and 1h were investigated while 4 h exposures were investigated in group 2.

No irritation or corrosion were noted in animals exposed to Lactic Acid Q88 for 3 min and 1h. Responses in animals exposed to the test material for 4 h were limited to very slight erythema which was noted at patch removal and 1 h after patch removal. Skin appeared normal at 24 h after patch removal.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Endpoint:
skin irritation: in vivo
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.
Reason / purpose for cross-reference:
read-across source
Irritation parameter:
overall irritation score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 4h
Score:
5.8
Max. score:
8
Irritation parameter:
overall irritation score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 28h
Score:
5.5
Max. score:
8
Irritation parameter:
overall irritation score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 52h
Score:
3.8
Max. score:
8
Irritation parameter:
overall irritation score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 76h
Score:
3.7
Max. score:
8
Irritation parameter:
erythema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 4h
Score:
3.7
Max. score:
4
Irritation parameter:
erythema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 28h
Score:
3.7
Max. score:
4
Irritation parameter:
erythema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 52h
Score:
3.7
Max. score:
4
Irritation parameter:
erythema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 76h
Score:
3.7
Max. score:
4
Irritation parameter:
edema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 4h
Score:
2.2
Max. score:
4
Irritation parameter:
edema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 28h
Score:
1.8
Max. score:
4
Irritation parameter:
edema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 52h
Score:
0.2
Max. score:
4
Irritation parameter:
edema score
Remarks:
Intact skin
Basis:
mean
Time point:
other: 76h
Score:
0
Max. score:
4
Irritation parameter:
erythema score
Remarks:
Intact skin
Time point:
24/48/72 h
Remarks on result:
not measured/tested
Remarks:
Other time points measured
Irritation parameter:
edema score
Remarks:
Intact skin
Time point:
24/48/72 h
Remarks on result:
not measured/tested
Remarks:
Other time points measured
Irritant / corrosive response data:
See table 1 in the section "Any other information on results incl. tables".

After 4 hours the dermal effects generally observed in all rabbits consisted of very slight to slight ischemic necrosis, moderate to severe haemorrhages and slight or moderate oedema.

After 28 hours the dermal effects observed generally consisted of very slight to slight ischemic necrosis, moderate haemorrhages, slight or moderate incrustation and slight: oedema.

During the course of the following two days ischemic necrosis, haemorrhages and oedema were no longer observed. The application sites generally became crater-shaped with a central sunken area which was moderately or severely encrusted, and a surrounding, raised border of non-necrotic skin showing well-defined erythema.

After 7 days this picture had hardly changed, apart from the clearance of erythema. The central sunken areas of the application sites generally showed moderate to severe incrustation. At the end of the observation period, after 3 weeks, some signs of healing were observed at the edges of the encrusted skin areas which had been in contact with the test material. In the new skin visible under the crust edges coming off from the treated skin, formation of scar tissue

could be observed whereas hair growth was absent. There were no distinct differences between reactions of the intact skin and those of the abraded skin.

On the basis of observations in earlier experiments with comparable results, performed at the performing laboratory, the authors state that it is expected that the old necrotic skin will be ejected and that: the formation of scar tissue will be continued. This scar tissue forned already or yet to be formed is not considered a reversible skin alteration.

Table 1: INDIVIDUAL AND AVERAGE SKIN IRRITATION SCORES OF LACTIC ACID (88%), AFTER 4, 28, 52 AND 76 HOURS

Rabbit no.

Intact skin

4 h

28 h

52 h

76 h

A

B

A

B

A

B

A

B

3231

4

2

4

2

4

0

4

0

3232

4

2

4

2

4

0

4

0

3233

4

3

4

2

4

0

4

0

3234

4

3

4

2

4

0

4

0

3235

2

1

2

1

2

1

2

0

3236

4

2

4

2

4

0

4

0

 

 

 

 

 

 

 

 

 

average (A+B)

5.8

5.5

3.8

3.7

Rabbit no.

Abraded skin

4 h

28 h

52 h

76 h

A

B

A

B

A

B

A

B

3231

4

2

4

2

4

0

4

0

3232

4

2

4

2

4

0

4

0

3233

4

3

4

2

4

0

4

0

3234

4

2

4

2

4

0

4

0

3235

4

2

4

2

4

0

4

0

3236

4

2

4

2

4

0

4

0

 

 

 

 

 

 

 

 

 

average (A+B)

6.2

6.0

4.0

4.0

A = erythema

B = oedema

Interpretation of results:
Category 1 (corrosive) based on GHS criteria
Conclusions:
Under the given conditions, the test item is corrosive to the skin.
Executive summary:

A sample of lactic acid (88%) was examined for acute dermal irritating/corrosive properties in an experiment (OECD 404) with six albino rabbits.

After 4 hours the dermal effects generally observed in all rabbits consisted of very slight to slight ischemic necrosis, moderate to severe haemorrhages and slight or moderate oedema. After 28 hours the dermal effects observed generally consisted of very slight to slight ischemic necrosis, moderate haemorrhages, slight or moderate incrustation and slight: oedema.Three weeks after treatment moderate to severe incrustation, formation of scar tissue and absence of hair growth were observed.

On the basis of the results obtained it was concluded that:

- lactic acid (88%) is severely irritating to the skin of albino rabbits

- lactic acid (88%) is corrosive to the skin of albino rabbit

Based on the results and in accordance with the harmonised classification for L-(+)-lactic acid, the test substance is considered to be corrosive to the skin.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Endpoint:
skin irritation: in vivo
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.
Reason / purpose for cross-reference:
read-across source
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 1h and 1, 2, 3, 7, 14, 21d
Score:
0
Max. score:
8
Reversibility:
other: not applicable
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
erythema score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
erythema score
Basis:
mean
Time point:
7 d
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
erythema score
Basis:
mean
Time point:
14 d
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
erythema score
Basis:
mean
Time point:
21 d
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
edema score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Remarks on result:
no indication of irritation
Remarks:
There was some minor superficial wounds and slight small crusts at application site and non-treated skin areas observed in 2 pigs at 24-28 h after 1-4 h of application duration. They were no longer detectable by 72 h after exposure.
Irritation parameter:
edema score
Basis:
mean
Time point:
7 d
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
edema score
Basis:
mean
Time point:
14 d
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Irritation parameter:
edema score
Basis:
mean
Time point:
21 d
Score:
0
Remarks on result:
no indication of irritation
Remarks:
After application duration of 3 minutes, 1 hour or 4 hours
Interpretation of results:
other: not irritating
Conclusions:
Under the given conditions the test item is not irritating to the skin of pigs.
Executive summary:

In a dermal irritation study, a sample of lactic acid (88%) was examined for acute dermal irritating/ corrosive properties with three pigs. In each animal, the test substance was brought into contact with three separate areas of shaved dorsal skin for 3 and 60 minutes and for 4 hours, respectively. The test sample did not cause any skin irritation when it was brought into contact with the dorsal skin of pigs for 3 or 60 minutes or for 4 hours. On the basis of the results; obtained in the present study with pigs, it was concluded that, according to the EEC-standards, lactic acid (88%) is not irritating or corrosive to skin.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Endpoint:
skin irritation: in vivo
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.
Reason / purpose for cross-reference:
read-across source
Irritation parameter:
erythema score
Basis:
other: at 10 of 12 abraded sites
Time point:
other: 30 to 60 minutes
Score:
ca. 4
Max. score:
4
Reversibility:
not specified
Remarks on result:
positive indication of irritation
Remarks:
24-hour exposure period
Irritation parameter:
edema score
Basis:
other: at 11 of 12 intact test sites
Time point:
other: 30 to 60 minutes
Score:
ca. 4
Max. score:
4
Reversibility:
not specified
Remarks on result:
positive indication of irritation
Remarks:
24-hour exposure period
Irritation parameter:
erythema score
Basis:
other: number of abraded sites
Time point:
24/48/72 h
Reversibility:
not specified
Remarks on result:
not measured/tested
Remarks:
Only evaluated 30 to 60 minutes after test item removal
Irritation parameter:
edema score
Basis:
other: number of intact test sites
Time point:
24/48/72 h
Reversibility:
not specified
Remarks on result:
not measured/tested
Remarks:
Only evaluated 30 to 60 minutes after test item removal
Irritant / corrosive response data:
The following were observed at the evaluations done at 30 to 60 minutes after test article removal (Grading system according to Draize 1979):
- Severe erythema (grade 4) at 10 of the 12 abraded test sites (on 5 animals) and at 7 of the 12 intact test sites on 4 of the same animals. Moderate to severe erythema (grade 3) at the 2 remaining abraded and 5 remaining intact test sites (all sites on one animal and one or both intact sites on 2 animals).
- Severe edema (grade 4) at 11 of 12 intact and 11 of 12 abraded test sites, and slight edema (grade 2) at one intact site and one abraded site on one animal.
- Blanching at both abraded sites on each animal, and at both intact sites on 5 animals.
- Yellow-brown color of skin at all sites on 3 animals, at both abraded sites on one animal, and at one intact site and both abraded sites on a fifth animal.
- Red exudate at one intact site on one animal.
- Skin missing at all sites on one animal, at one intact site and both abraded sites on one animal, and at one intact site or one abraded site on 2 other animals. No other dermal reactions were observed at the evaluations done at 30 to 60 minutes after test article removal.
One animal (BB5196) was observed by an attending veterinarian and the following comments were noted:
Both lesions in the left lateral thoracic and abdominal wall were circular and approximately 4 cm. in diameter. Tags of necrotic skin were observed around the circumference while the entire center (greater than a 3 cm. circle) was totally denuded of all layers of skin. The peritoneum was intact, and hemorrhage from the peritoneal vessels and skin vessels around the circumference was evident. Without medical treatment, these and similar lesions were expected to become secondarily infected
resulting in the animals death. Termination of the study was recommended by the veterinarian. No abnormal clinical signs were observed and no mortalities occurred prior to sacrifice after the 30- to 60-minute evaluations.
Interpretation of results:
other: highly irritating
Conclusions:
Under the given conditions, the test item is highly irritating to the skin of rabbits.
Executive summary:

L(+)-lactic acid, was evaluated for primary dermal irritation potential when applied to 2 intact and 2 abraded test sites on the skin of 6 albino rabbits and covered with impervious bandages for 24 hours. These 24 test sites were evaluated for erythema, edema, and other lesions at 30 to 60 minutes after test article removal. This study was designed to comply with the procedures described in the EPA/OPP Guidelines, 1982. The following were observed at 30 to 60 minutes after test article removal: Severe erythema was observed at all test sites on 3 animals, and at both abraded sites on 2 other animals and at one intact site on one of these 2 animals. Moderate to severe erythema was observed at all test sites on one animal, and at one or both intact sites on 2 animals. Severe edema was observed at all test sites on 5 animals and at one intact site and one abraded site on the sixth animal. Slight edema was observed at the other 2 sites on the sixth animal. Blanching was observed at both abraded sites on all animals and at both intact sites on 5 of these animals. Yellow-brown colour of the skin was observed at all sites on 3 animals and at either 2 or 3 test sites on 2 animals. A red exudate was observed at one intact site on one animal. Skin was missing at all test sites on one animal, at one intact and both abraded sites on one animal, and at one intact site or one abraded site on 2 other animals. No other dermal reactions were observed during the study. This study was terminated after the 30- to 60-minute evaluations upon the recommendation of an attending veterinarian due to the severity of the reactions observed. No abnormal clinical signs were observed, and no mortalities occurred prior to sacrifice after the 30- to 60-minute evaluations. Based on the results, the test item is considered to be highly irritating to the skin of rabbits.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
For details and justification of read-across please refer to the report attached in section 13 of IUCLID.
Reason / purpose for cross-reference:
read-across source
Irritation / corrosion parameter:
other: MTT conversion
Remarks:
in OD560 per gram dry weight
Run / experiment:
30 min exposure / Rabbit skin
Value:
37.6
Vehicle controls validity:
not examined
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
other: Statistically significantly lower than the non-exposed control group (p< 0.05)
Irritation / corrosion parameter:
other: MTT conversion
Run / experiment:
30 min exposure / Human skin
Value:
19.45
Vehicle controls validity:
not examined
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
other: comparable to negative control
Irritation / corrosion parameter:
other: Epidermal cell proliferation in skin organ cultures
Run / experiment:
30 min exposure / Human skin
Value:
ca. 59
Vehicle controls validity:
not examined
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
other: no statistically significant deviation from control
Irritation / corrosion parameter:
other: Epidermal cell proliferation in skin organ cultures
Run / experiment:
30 min exposure / Rabbit skin
Value:
ca. 55
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
other: no statistically significant deviation from control
Interpretation of results:
other: rabbit skin was clearly more sensitive to the test item than human skin
Conclusions:
The effect of lactic acid on rabbit and human skin was studied in vitro in skin organ cultures. Toxicity was measured by epidermal cell proliferation and by the conversion of a tetrazolium salt (MTT). Based on the MTT assay and inhibition of epidermal cell proliferation, rabbit skin was clearly more sensitive to the test item than human skin.
Executive summary:

Lactic acid was examined for in vitro skin toxicity in skin organ cultures. Toxicity was determined by measuring epidermal cell proliferation and the conversion of the tetrazolium salt MTT. In rabbit skin, MTT conversion was statistically significantly reduced after exposure to HS88. Possible species-specific irritant effects of lactic acid were tested in vitro by comparing rabbit skin to human skin. Based on the MTT assay and inhibition of epidermal cell proliferation, rabbit skin was clearly more sensitive to HS88 than human skin. A possible explanation for this difference is a lower skin absorption of the test substance in human skin, since rabbit skin is generally more permeable for topically applied chemicals than human skin (ECETOC, 1993). The anionic surfactant sodium dodecyl sulfate (SDS) was used as a reference substance to enable comparison of the in vitro results of this study to previous data obtained with the skin organ culture model. Exposure of rabbit skin for 30 minutes to 5% SDS induced a decrease of MTT conversion of approximately 15%. Human skin was less sensitive to SDS than rabbit skin. It has been reported that 5% SDS is a moderate irritant in rabbits (Gad et al., 1986) and human volunteers (Willis et al., 1988). In conclusion, this in vitro skin toxicity study revealed that rabbit skin was more sensitive to HS88 than human skin.

This information is used in a read-across approach in the assessment of the target substance. For justification of read-across please refer to the attached read-across report (see IUCLID section 13).

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (corrosive)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vitro / ex vivo
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.
Reason / purpose for cross-reference:
read-across source
Irritation parameter:
cornea opacity score
Remarks:
after 240 min
Run / experiment:
1
Value:
ca. 4
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
cornea opacity score
Remarks:
after 240 min
Run / experiment:
2
Value:
ca. 4
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
cornea opacity score
Remarks:
after 240 min
Run / experiment:
3
Value:
ca. 4
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
percent corneal swelling
Remarks:
after 240 min
Run / experiment:
1
Value:
ca. 31
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
percent corneal swelling
Remarks:
after 240 min
Run / experiment:
2
Value:
ca. 26
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
percent corneal swelling
Remarks:
after 240 min
Run / experiment:
3
Value:
ca. 28
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
fluorescein retention score
Remarks:
after 30 min
Run / experiment:
1
Value:
ca. 3
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
not determinable
Irritation parameter:
fluorescein retention score
Remarks:
after 30 min
Run / experiment:
2
Value:
ca. 3
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Irritation parameter:
fluorescein retention score
Remarks:
after 30 min
Run / experiment:
3
Value:
ca. 3
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
not examined
Remarks on result:
positive indication of irritation
Interpretation of results:
Category 1 (irreversible effects on the eye) based on GHS criteria
Conclusions:
In conclusion, based on the given conditions the test item is considered severely irritating to eyes.
Executive summary:

Lactic acid 88% (sample code HS88), was examined undiluted for eye irritating/corrosive potential in an ex vivo bioassay, namely the Enucleated Eye Test with chicken eyes (CEET). The eyes were collected as waste material from a slaughter-house for chickens, which were killed for human consumption. HS88 induced severe corneal effects. On the basis of the results obtained with this in vitro (ex vivo) assay, HS88 can be considered severely irritating to eyes.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

There are no reliable studies available for the assessment of the skin irritation and eye irritation endpoints with the target substance, D-(-)-lactic acid. Therefore, data from a suitable read-across partner, L(+)-lactic acid was used to assess the skin and eye irritation potential of the target substance. For details and justification of read-across please refer to the report attached in IUCLID section 13.

In in vivo and in vitro tests with L(+)-lactic acid, the skin irritation potential of the test item was assessed using the weight of evidence approach.

Based on the results from in vivo studies conducted with rabbits, the test substance must be considered as corrosive to the rabbit skin; however, it is not irritating at all to guinea pig skin or porcine skin and in an in vitro test it was shown that lactic acid 88 % was toxic to a skin cell patch of rabbit skin cells, but not to human skin cells. Therefore, it can be stated that rabbit skin is more sensitive to lactic acid irritation than other skin types, including human skin.

In accordance with the harmonized classification for the source substance L(+)-lactic acid, classification as Skin Corr. 1C, H314 is also warranted for D-(-)-lactic acid.

An in vitro enucleated eye test with chicken eyes was conducted equivalent to OECD TG 438 with L(+)-lactic acid (88%). The eyes were collected as waste material from a slaughterhouse for chickens, which were killed for human consumption. The test item induced severe corneal effects. Therefore classification for eye damage (Eye Dam.1, H318) is warranted according to CLP Regulation 1272/2008.

As the assessment is based on data derived from studies conducted with the enantiomer of D-(-)-lactic acid, namely L(+)-lactic acid, the harmonized classification according to Annex VI of CLP Regulation 1272/2008 of the source substance as Skin Corr. 1C, H314, Eye Dam. 1, H318 and supplementary labelling as EUH071 (corrosive to the respiratory tract) is also applicable to the target substance D-(-)-lactic acid.

Justification for classification or non-classification

As the assessment is based on data derived from studies conducted with the enantiomer of D-(-)-lactic acid, namely L(+)-lactic acid, the harmonized classification according to Annex VI of CLP Regulation 1272/2008 of the source substance as Skin Corr. 1C, H314, Eye Dam. 1, H318 and supplementary labelling as EUH071 (corrosive to the respiratory tract) is also applicable to the target substance D-(-)-lactic acid.