Propanoic acid, 2-hydroxy-, propyl ester, (2S)-

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1994-06-14 to 2020-02-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

adopted in1987

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted 31st July 1992

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

propyl (2S)-2-hydroxypropanoate

EC Number:

611-025-7

Cas Number:

53651-69-7

Molecular formula:

C6H12O3

IUPAC Name:

propyl (2S)-2-hydroxypropanoate

Specific details on test material used for the study:

- Name of test material (as cited in study report): n-propyl lactate
- Analytical purity: 99.5%
- Lot/batch No.: 3
- Appearance: clear, colourless liquid
- Storage conditions: ambient

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Broekman Instituut B.V., Someren, The Netherlands
- Age at study initiation: young adult
- Weight at study initiation: 2940 g
- Housing: individually in a stainless steel cage, fitted with a perforated floor
- Diet: standard laboratory rabbit diet, ad libitum
- Water: tap water, ad libitum
- Acclimation period: 27 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3
- Humidity (%): 42-82.5
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL

VEHICLE
- Amount(s) applied (volume or weight with unit): no vehicle used

Duration of treatment / exposure:

An amount of 0.1 mL of the test substance was instilled in the conjunctival cul-de-sac of the right eye. After administration, the upper and lower eye lid were carefully closed and subsequently held together for at least one second before releasing, to prevent loss of material. The left eye remaining untreated, served as a control.

Observation period (in vivo):

42 days post-treatment (scoring: 1, 24, 48 and 72 hours and 7, 14, 21, 25, 28, 35 and 42 days after treatment)

Number of animals or in vitro replicates:

one animal (due to severe effects observed)

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no
- Time after start of exposure: non-relevant

SCORING SYSTEM: in accordance with the OECD guideline 405
The reactions were scored 1 h, 24, 48 and 72 h, as well as at 7, 14, 21, 25, 28, 35, and 42 days after treatment

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 42 d

Remarks on result:

positive indication of irritation

Results 2

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 14 d

Remarks on result:

positive indication of irritation

Results 3

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

fully reversible within: 25 d

Remarks on result:

positive indication of irritation

Results 4

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

fully reversible within: 25 d

Remarks on result:

positive indication of irritation

Irritant / corrosive response data:

See Table 1 in box 'Any other information on results incl. tables'.

Any other information on results incl. tables

Table 1: Individual irritation scores given to the ocular lesions exerted by the test material.

Time post-treatment	Corneal opacity	Iris effect	Conjunctivae		Ocular discharge
			Redness	Chemosis
1 h	2(4)	1	2	3	3
24 h	2(4)	1	3^1	3	3
48 h	2(4)	1	3^1	3	3^2
72 h	2(4)	1	3^1	3	3^2
7 d	2(4)^3	1	2	2	1
14 d	2(2)^3	0	2	2	0
21 d	1(2)^3	0	1	1	0
25 d	1(4)^3°	0	0	0	0
28 d	1(4)^3°	0	0	0	0
35 and 42 d	1(3)^3°	0	0	0	0

( ) = area of opacity; 2 = half area, 3 = three quart area, 4 = entire cornea

1= severe ischemic necrosis; 2= haemorrhagic discharge; 3=vascularization of the cornea; ° = slight ulcus corneae

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Conclusions:

In an acute eye irritation/corrosion study conducted according to the OECD TG 405, n-propyl lactate was found as severely irritating to the eyes of rabbits.

Executive summary:

In an eye irritation/ corrosion study conducted according to the OECD TG 405, 0.1 mL of n-propyl lactate (purity 99.5%) was instilled into the conjunctival sac of the right eye of 1 young adult New Zealand White albino rabbit. The left eye remaining untreated, served as a control. The eyes were not washed after treatment. The animal then was observed for 42 days. Irritation was scored by the method of Draize.

The test substance caused moderate corneal opacity, slight iritis, severe redness, severe ischemic necrosis, and severe swelling of the conjunctivae, and severe ocular discharge in this rabbit. In addition, vascularization of the cornea and ulcus corneae were observed. At 21 days after treatment, residual corneal effects were still present. Therefore, the observation period was extended with another 3 weeks. After this period, vascularization of the cornea, ulcus corneae, and corneal opacity were still observed. Based on the results of this study, the test item Propyl (S)-lactate is severely irritating to the eye and in accordance with CLP Regulation 1972/2008 classification as Eye Dam. 1 (H318) is warranted.