Lithium bis(oxalato)borate

Endpoint summary

Description of key information

Based on the in vitro skin irritation study with a human skin model and an in vivo skin irritation study with New Zealand White rabbits, lithium bis(oxalato)borate (LiBOB) is considered to be not irritating.
According to the results of a HET-CAM test with LiBOB, it is assumed that the test item does not cause eye irritation. This result involves the performance of an in vivo eye irritation study as stated in Reach Regulation 1907/2006, Annex XI, section 1.4.
Based on the results of the in vivo eye irritation study on three New Zealand White rabbits, lithium bis(oxalato)borate causes irreversible effects to the eyes.

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:

2011-11-22 to 2011-11-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline compliant study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

24th April 2002

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

16th June 2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Version / remarks:

August 1998

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: S & K LAP Kft., 2173 Kartal, Császár út 135, Hungary
- Age at study initiation: 10 weeks old
- Weight at study initiation: 3191-3340 g
- Housing: housed individually in metal cages
- Diet (e.g. ad libitum): P. Strengthened Female Hare Mixed diet, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: 19 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

occlusive

Preparation of test site:

other: clipped

Vehicle:

unchanged (no vehicle)

Controls:

other: untreated skin served as a control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g

Duration of treatment / exposure:

4 hours

Observation period:

1, 24, 48, 72 hours

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: back and flanks
- coverage: an approximately area of 6 cm^2 of intact skin
- Type of wrap if used: plastic wrap

REMOVAL OF TEST SUBSTANCE
- Washing (if done): body temperature water used
- Time after start of exposure: 4 hours

SCORING SYSTEM: by Draize et al. (1959)

Irritation parameter:

erythema score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: very slight erythema and crust was found after 24 h

Irritation parameter:

edema score

Remarks:

mean

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.66

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: very slight erythema was detected after 24 and 48 h

Irritation parameter:

edema score

Remarks:

mean

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 h

Remarks on result:

other: very slight erythema after 24 h

Irritation parameter:

edema score

Remarks:

mean

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Interpretation of results:

other: EU GHS criteria not met

Conclusions:

Based on the skin irritation study the test substance was not irritating to the intact skin of New Zealand white rabbits.

Executive summary:

The acute skin irritation study of the test item lithium bis(oxalato)borate (LiBOB) was performed in New Zealand White rabbits according to OECD guideline 404 and EU method B.4. The irritation effect of the test item was evaluated according to the Draize method. The test item was administered in pure state, in a single dose of 0.5 g, to the hairless skin of three experimental rabbits. The untreated skin of each animal served as control. After 4 hours the rest of the test item was removed with water. The animals were examined at 1, 24, 48 and 72 hours after the patch removal. One hour after the patch removal very slight and well defined erythema and very slight edema were observed. 24 hours after the patch removal very slight erythema was found in all animals and crust were recorded in one animal. 72 hours after the patch removal no primary irritation symptoms, like erythema and edema or other signs occurred on the treated skin surfaces, so the study was terminated at this time. The animal’s individual mean scores (considering readings at 24, 48 and 72 hours after the patch removal) were as follows:

- erythema: 0.33, 0.66, 0.33

- edema: 0.00, 0.00, 0.00

During the study the control area was symptom-free. General state and the behavior of animals were normal throughout the study period. There were no notable body weight changes during the contact and observation period. The observed symptoms were evaluated as fully reversible alterations. From this follows lithium bis(oxalato)borate is non irritating to the intact skin of New Zealand white rabbits. (TOXICOOP, 2012)

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:

2010-11-02 to 2010-11-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline compliant study.

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

April 24th 2002

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Myrtle´s Rabbitry, Inc., Thompsons Station, TN, USA
- Age at study initiation: ca. 4 months old (born on 2010-07-20)
- Weight at study initiation: ca. 2.7 kg
- Housing: individually in suspended cages
- Diet (e.g. ad libitum): PMI Rabbit Chow (Diet# 5321), ad libitum
- Water (e.g. ad libitum): tap water, ad libitum

ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12/12
- animal room was temperature controlled.

Vehicle:

unchanged (no vehicle)

Controls:

other: The contralateral eye served as a control.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 83.2 mg (0.1 mL equivalent)

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

21 days

Number of animals or in vitro replicates:

3 (one male, two females)

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: washing was not done.

TYPE AND FREQUENCY OF OBSERVATIONS
Using a Mini-Maglite flashlight equipped with a high intensity bulb, the treated eye of each rabbit was examined for irritation of the cornea, iris and conjunctiva at 1, 24, 48 and 72 hours and again on days 7, 14 and 21 postdose. The control eyes were observed at the same time periods. Sodium fluorescein dye procedures were used at the 24-hour observation interval up to day 21. The eye was examined with the aid of an ultraviolet light source. Ocular reactions were graded according to the numerical Draize technique. Additional signs were described.
Body weights were recorded pretest and at termination.
Observations for toxicity and pharmacological effects were recorded at each ocular observation period and mortality observations were performed daily. All animals were humanely sacrificed using CO2 following study termination.

ANALYSIS OF DATA
The primary eye irritation score for each rabbit was calculated from the weighted Draize scale.

SCORING SYSTEM: according to Draize, J.H. et al. (1944)

TOOL USED TO ASSESS SCORE: hand-slit lamp and fluorescein

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #1

Time point:

24 h

Score:

22

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #1

Time point:

48 h

Score:

98

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #1

Time point:

72 h

Score:

98

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #2

Time point:

24 h

Score:

40

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #2

Time point:

48 h

Score:

98

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #2

Time point:

72 h

Score:

98

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #3

Time point:

24 h

Score:

73

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #3

Time point:

48 h

Score:

71

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

overall irritation score

Remarks:

sum of cornea, iris and conjunctiva score

Basis:

animal #3

Time point:

72 h

Score:

71

Max. score:

110

Reversibility:

not fully reversible within: 21 days of observation period.

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Remarks on result:

not measured/tested

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Remarks on result:

not measured/tested

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Remarks on result:

not measured/tested

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Remarks on result:

not measured/tested

Irritant / corrosive response data:

Corneal opacity, iritis and conjunctival irritation, noted in 3/3 eyes, persisted to day 21.

Other effects:

There were no abnormal physical signs noted during the observation period. Body weight increases were normal.

Interpretation of results:

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

Conclusions:

Based on the results of this in vivo eye irritation study on three New Zealand White rabbits, lithium bis(oxalato) borate causes irreversible effects to the eyes.

Executive summary:

An eye irritation study has been conducted with lithium bis(oxalato)borate in accordance with OECD guideline 405. Three healthy New Zealand White rabbits, free from evidence of ocular irritation and corneal abnormalities, were dosed with lithium bis(oxalato)borate. The test article (0.1 mL equivalent (83.2 mg)) was placed into the conjunctival sac of one eye of each rabbit. The eyes were examined pretest and scored by Draize technique at 1, 24, 48 and 72 hours and again on days 7, 14 and 21 postdose. The control eyes were observed at the same time periods. Sodium fluorescein dye procedures were used at the 24 -hour observation interval up to day 21. Observations for toxicity and pharmacological effects were recorded at each ocular observation period and mortality observations were performed daily. Body weights were recorded pretest and at termination. Corneal opacity, iritis and conjunctival irritation, noted in 3/3 eyes, persisted to day 21. There were no abnormal physical signs noted during the observation period. Body weight increases were normal.

Lithium bis(oxalato)borate causes irreversible effects to the healthy eye of New Zealand White rabbits. (MB Research Laboratories, 2010)

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In vitro skin irritation

The study procedure employed a human skin model and was based on the following guidelines - Organisation for Economic Cooperation and Development (OECD), OECD Guidelines for Testing of Chemicals, Draft Proposal for a new guideline no. 431: In Vitro Skin Corrosion: Human Skin Model Test (Draft 20 February 2004). - European Economic Community (EEC). Adapting to technical progress for the twenty-sixth time Annex V of the EEC Directive 67/548/EEC, Part B: Methods for the Determination of Toxicity; B.40: "Skin corrosion". EEC Publication Commission Directive (08-06-2000). The study evaluates the corrosive properties of the test substance on a human three dimensional epidermal model (EpiDerm (EPI-200)). The possible corrosive potential of the test substance was tested through topical application for 3 minutes and 1 hour exposure. 25 mg of lithium bis(oxalato)borate was applied with 75 micro liter of Milli-Q water directly on top of the skin  tissue. The test substance was dissolved in the Milli-Q water and spread over the tissue. The positive control ( Potassium hydroxide, 8.0 N solution) had a mean relative tissue viability after 3 minutes exposure of less than 30 %. The negative control had a mean OD540 (Optical density 540 nm) higher than 0.8. The maximum inter tissue variability in viability between two tissues treated identically was less than 30 %. The maximum difference in percentage between the mean viability of two tissues and one of the two tissues was less than 15 %, indicating that the test system functioned properly.

Skin corrosion is expressed as the remaining cell viability after exposure to the test substance. The relative mean tissue viability obtained after 3 minutes and 1 hour treatment with the test substance compared to the negative control tissues was 89 % and 35 % respectively. Since the mean relative tissue viability for the test substance was not below 50 % after 3 minutes treatment and not below 15 % after 1 hour treatment the test substance is considered to be not corrosive. (NOTOX, 2004)

In vivo skin irritation

The acute skin irritation study of the test item lithium bis(oxalato)borate (LiBOB) was performed in New Zealand White rabbits according to OECD guideline 404 and EU method B.4. The irritation effect of the test item was evaluated according to the Draize method. The test item was administered in pure state, in a single dose of 0.5 g, to the hairless skin of three experimental rabbits. The untreated skin of each animal served as control. After 4 hours the rest of the test item was removed with water. The animals were examined at 1, 24, 48 and 72 hours after the patch removal. One hour after the patch removal very slight and well defined erythema and very slight edema were observed. 24 hours after the patch removal very slight erythema was found in all animals and crust were recorded in one animal. 72 hours after the patch removal no primary irritation symptoms, like erythema and edema or other signs occurred on the treated skin surfaces, so the study was terminated at this time. The animal’s individual mean scores (considering readings at 24, 48 and 72 hours after the patch removal) were as follows:

- erythema: 0.33, 0.66, 0.33

- edema: 0.00, 0.00, 0.00

During the study the control area was symptom-free. General state and the behavior of animals were normal throughout the study period. There were no notable body weight changes during the contact and observation period. The observed symptoms were evaluated as fully reversible alterations. From this follows lithium bis(oxalato)borate is non irritating to the intact skin of New Zealand white rabbits. (TOXICOOP, 2012)

in vitro eye irritation

The objective was to assess the eye irritation potential which is included in international regulatory requirements for the testing of chemicals. The HET-CAM Test is an alternative in vitro method for testing of severe eye/mucous membrane damage using the chorionallantoic membrane of fertilized, incubated hen eggs. Due to animal welfare reasons, the potential of severe irritation is determined in the HET-CAM in vitro system before deciding on a possible study in the rabbit as suggested in OECD Guideline 405 .

The chorioallantoic membrane (CAM) of twenty four White Leghorn eggs, incubated for 10 days, were dosed with 0.3 mL of the test substance. Two positive controls (0.1N NaOH and 1 % SDS) and a vehicle control were examined, too. For each substance 6 eggs were used. The eggs were observed continuously for five minutes immediately following dosing for the appearance of lysis (sec L), hemorrhage (sec H) and/or coagulation (sec C). In addition, the eggs were scored for severity at 1 and 5 minutes postdose. The irritating potential of the test article was classified based on the irritation score (IS) and the threshold concentration.

The mean IS for 0.1N NaOH and 1 % SDS were 14.96 and 9.75, respectively. The vehicle control, distilled water, had no adverse effects on the CAM. At 10 % (v/v) in distilled water, the IS of lithium bis(oxalato)borate was 0.41. The threshold concentration for this test article was greater than 10 %.

Based on the threshold concentration of greater than 10 % and the corresponding IS of 0.41, the irritating potential of lithium bis(oxalato)borate was determined as none to slight. These findings result in the performance of an in vivo eye irritation study as stated in Reach Regulation 1907/2006, Annex XI, section 1.4 in order to confirm the results of the in vitro study. (MB Research Laboratories, 2010)

In vivo eye irritation

An eye irritation study has been conducted with lithium bis(oxalato)borate in accordance with OECD guideline 405. Three healthy New Zealand White rabbits, free from evidence of ocular irritation and corneal abnormalities, were dosed with lithium bis(oxalato)borate. The test article (0.1 mL equivalent (83.2 mg)) was placed into the conjunctival sac of one eye of each rabbit. The eyes were examined pretest and scored by Draize technique at 1, 24, 48 and 72 hours and again on days 7, 14 and 21 postdose. The control eyes were observed at the same time periods. Sodium fluorescein dye procedures were used at the 24 -hour observation interval up to day 21. Observations for toxicity and pharmacological effects were recorded at each ocular observation period and mortality observations were performed daily. Body weights were recorded pretest and at termination. Corneal opacity, iritis and conjunctival irritation, noted in 3/3 eyes, persisted to day 21. There were no abnormal physical signs noted during the observation period. Body weight increases were normal.

Lithium bis(oxalato)borate causes irreversible effects to the healthy eye of New Zealand White rabbits. (MB Research Laboratories, 2010)

Justification for selection of skin irritation / corrosion endpoint:
GLP and guideline compliant study.

Justification for selection of eye irritation endpoint:
GLP and guideline compliant study.

Effects on eye irritation: corrosive

Justification for classification or non-classification

Based on the results of the acute skin irritation studies in vitro and in vivo, lithium bis(oxalato)borate is not subjected to classification and labelling for skin irritating effects according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP/GHS).

Based on the acute eye irritation studies in vitro and in vivo, lithium bis(oxalato)borate is classified as severly eye damaging (Xi, R41) according to Directive 67/548/EEC (DSD) and severly eye damaging cat. 1 (H318) according to Regulation (EC) No 1272/2008 (CLP/GHS).