Dilactide

Endpoint summary

Description of key information

L-lactide (purity >99.5%) was tested negative for acute dermal irritating properties in a study conducted according to OECD 404. The substance caused reversible eye irritating effects in an acute eye irritation/corrosion study in rabbits conducted according to OECD 405. L-lactide is a suitable read across partner as dilactide is a mixture of D- and L-lactide isomers.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin corrosion: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro skin irritation study does not need to be conducted because adequate data from an in vivo skin irritation study are available

Reference 2

Endpoint:

skin irritation: in 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:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

At 1-72 hours after treatment, no signs of skin irritation were observed in any of the three rabbits.

Other effects:

None

Interpretation of results:

other: CLP criteria not met

Conclusions:

In conclusion, in the acute dermal irritation/corrosion study conducted according to OECD 404, the test item L-lactide is considered to be non-irritating.

Executive summary:

In a primary dermal irritation study conducted according to OECD Guideline 404, female young adult SPF bred New Zealand White albino rabbits (n= 3) were dermally exposed to 0.5 g of L-lactide (purity: >99.5%) under semi-occlusive for 4 hours. Animals then were observed 1, 24, 48 and 72 hours after exposure. Irritation was scored by the method of Draize et al. (1944).

In this study, L-lactide did not cause any skin effects. Thus, under the conditions of this study, L-lactide can be considered as non-irritating.

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:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro eye irritation study does not need to be conducted because adequate data from an in vivo eye irritation study are available

Reference 2

Endpoint:

eye irritation: in 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

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 7d

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Max. score:

3

Reversibility:

fully reversible within: 7d

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

fully reversible within: 7d

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.3

Max. score:

2

Reversibility:

fully reversible within: 7d

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2.7

Max. score:

3

Reversibility:

fully reversible within: 7d

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1.7

Max. score:

4

Reversibility:

fully reversible within: 7d

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

fully reversible within: 7d

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.7

Max. score:

4

Reversibility:

fully reversible within: 7d

Irritant / corrosive response data:

At 1 hour after treatment, slight comeal opacity (two rabbits), slight iritis (one rabbit), slight redness and slight or severe swelling of the conjunctivae (three rabbits), and severe ocular discharge (two rabbits) were observed.
At 24 hours after treatment, slight corneal opacity (one rabbit), slight iritis (one rabbit), slight or severe redness and moderate swelling of the conjunctivae (two rabbits), and moderate ocular discharge (two rabbits) were observed. In addition, one rabbit showed haemorrhages on the nictitating membrane.
At 48 hours after treatment, the eye effects had cleared in one rabbit, whereas the other two rabbits showed moderate comeal opacity (one rabbit), severe redness and moderate swelling of the conjunctivae, and moderate ocular discharge. The haemorrhages on the nictitating membrane was still observed in one rabbit.
At 72 hours after treatment, slight comeal opacity (one rabbit), moderate or severe redness and slight swelling of the conjunctivae (two rabbits), slight ocular discharge (one rabbit) and haemorrhages on the nictitating membrane (one rabbit) were observed.
At 7 days after treatment, all eye effects had cleared completely.

Table 1: Mean values for corneal opacity, iritis, redness and swelling of the conjunctivae of each rabbit scored at 24, 48, 72 hours after treatment with L-lactide

Animal	Opacity	Iritis	Redness	Swelling
A19	0.0	0.0	0.3	0.0
A21	1.3	0.3	2.7	1.7
A23	0.0	0.0	3.0	1.7

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

In conclusion, in this acute eye irritation/corrosion study conducted according to OECD 405, L-lactide is inducing reversible irritation in the eyes of rabbits.

Executive summary:

L-lactide (purity > 99.5%) was tested for acute eye irritating properties in an experiment with three albino rabbits according to OECD guideline 405. Undiluted substance (0.01 mL) was powdered onto the cornea and caused slight to moderate corneal opacity, slight iritis, slight to severe redness (mean score >2 in two of three animals) and slight to severe swelling on the conjunctivae. At 7 days after treatment, all eye effects had cleared completely.

Based on the results it was concluded, that L-lactide is irritating to the eyes of rabbits and needs be to classified as eye irritant (CLP category 2) according to CLP Regulation 1272/2008.

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 (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Only data from L-lactide is available. L-lactide is a suitable read across partner as dilactide is a mixture of D- and L-lactide isomers. L-lactide (purity >99.5 %) was tested negative for acute dermal irritating properties in a study conducted according to OECD 404. After a dermal exposure period of 4 hours no skin effects were observed in rabbits.

In contrast, L-lactide was irritating to the eyes of rabbits in an acute eye irritation study conducted according to OECD 405. The effects were reversible within seven days after treatment. Based on these results from the read across partner L-lactide, dilactide is considered to be not irritating to skin, but irritating to the eye.

Justification for classification or non-classification

The read-across partner L-lactide did not cause any skin effects in an acute dermal irritating study conducted in accordance with OECD 404. Based on these results, dilactide does not warrant classification for skin irritation.

L-lactide was irritating to the eyes of rabbits in a study conducted according to OECD 405. The irritation was reversible with mean scores for conjunctivae redness (24, 48, 72 h) of ≥ 2.7 in two of three animals. Therefore, based on the results from the read across partner L-lactide, dilactide meets the classification criteria according to CLP Regulation 1272/2008. The substance is classified for reversible eye irritation (Eye Irrit. 2, H319).