Tetrasodium N,N-bis(carboxylatomethyl)-L-glutamate

Endpoint summary

Description of key information

GLDA-Na4 is considered not to have significant acute oral, dermal and respiratory toxicity (see further at Discussion).

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD 401 protocol study under GLP without significant deviations

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River UK
- Age at study initiation: 6-9weeks
- Weight at study initiation: males 131-150 g females 124-135 gr
- Fasting period before study: 1 night
- Housing: groups of 5 by sex in polyprop cages with woodflakes
- Diet (e.g. ad libitum): ad lib
- Water (e.g. ad libitum): at lib
- Acclimation period:five days min.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-23
- Humidity (%): 48-70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From:July 4 1994 To: July 19, 1994

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/ml
- Amount of vehicle (if gavage): 10 ml/kg
- Justification for choice of vehicle: high water solubility
- Lot/batch no. (if required):
- Purity: distilled


MAXIMUM DOSE VOLUME APPLIED:
10 ml/kg equals ~ 1.5 ml for the heaviest animals

Doses:

2000 mg /kg

No. of animals per sex per dose:

5 M / 5 F

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: 0.5, 1, 2 and 4 hrs after dosing, then daily for 14 days
- weighing: day ) day 0, pre-dosing, days 1,2,3,7, 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, gross pathology

Statistics:

not applicable

Preliminary study:

500 and 2000 mg/kg bw (sequential, 24 hr interval)
1 female per dose
observations: 0.5, 1,2,4 hrs post-dosing, daily for 7 days
No clinical signs of toxicity at 2000 mg/kg bw.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

none

Clinical signs:

other: none

Gross pathology:

none

Other findings:

None

In a separate study on this compound (Micronucleus test; Durward, 1995) mice were orally dosed with GBS-5 at levels of 2500 or 5000 mg/kg bw (1 male and 1 female per level). There was no mortality. Clinical signs were observed i n animals dosed with GBS-5 via the oral route and were as follows: hunched posture, lethargy, decreased respiratory rate, ptosis and splayed gait.

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information

Conclusions:

Acute median lethal dose (LD50) > 2000 mg/kg bw . As there were no toxic signs at all at this level, no classification in category V (GHS) is needed.

Executive summary:

The study was performed to assess the acute toxicity of the test material, GBS-5, following a single oral administration to the Sprague-Dawley strain rat. The procedure permitted identification of the ‘discriminatory dose’ (the highest of the pre-set dose levels which could be administered without causing compound related mortality). The study was performed according to Method B1 bis of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC). Following a range-finding study, a group of ten fasted animals (five male and five female) was given a single, oral dose of the test material at a dose level 2000 mg/kg bodyweight. The animals were observed for 14 days after the day of dosing and were then killed for gross pathological examination. There were no deaths. No clinical signs of toxicity were noted. All animals showed expected gains in bodyweight over the study period. No abnormalities were noted at necropsy. The acute median lethal dose (LD50) of the test material was found to be greater than 2000 mg/kg bodyweight. The test material was considered not to have significant acute toxicity. Because of the absence of effects at 2000 mg/kg, the test material was not classified in Category V according to OECD-GHS (2000 -5000 mg/kg bw).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

Two reliable studies available

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

November 2008 - December 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to standard protocol and under GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: 7 weeks old (received at age of 6 weeks)
- Weight at study initiation: 233.6 g (average weight males), 165.3 g (average weight females)
- Fasting period before study: not applicable
- Housing: 5 males or 5 females per cage, except during exposure: housed individually in holders
- Diet (e.g. ad libitum): ad lib, except during exposure
- Water (e.g. ad libitum): ad lib, except during exposure
- Acclimation period: 8 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24°C
- Humidity (%): generally within 40-70%
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12-hour light, 12-hour dark cycle


IN-LIFE DATES: From: December 4, 2008 To: December 18, 2008

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

other: water

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: nose-only inhalation chamber, a modification of the chamber manufactured by ADG Developments Ltd., Codicote, UK
- Exposure chamber volume: ca. 60 litres
- Method of holding animals in test chamber: individually, in plastic animal holders
- Source and rate of air: dry compressed air, 20.0 normal Litres/minute (corresponding to 22.2 L/min at current T and pressure)
- Method of conditioning air: dry compressed air
- System of generating particulates/aerosols: to generate the test atmosphere, a solution of 50 wt% GLDA in water was passed via a peristaltic pump (Minipulse, Gilson, Villiers le Bel, France) to a compressed air driven atomizer (type 970/S, Schlick GmbH, Coburg, Germany); the air flow was measured using a mass stream meter (Bronkhorst Hi Tec, Ruurlo, The Netherlands).
- Method of particle size determination: Two particle size distribution measurements were performed (one before and one during exposure using the same settings). A 10-stage cascade impactor was used (Andersen, Atlanta, USA). The Mass Median Aerodynamic Diameter (MMAD) and geometric standard deviation (gsd) were calculated.
- Treatment of exhaust air: From the bottom of the unit the test atmosphere was led to an exhaust where it was filtered.
- Temperature, humidity, pressure in air chamber: The temperature and the relative humidity of the test atmosphere were recorded eight times during exposure at regular intervals (about twice per hour) using a CAN transmitter (G.Lufft Mess- und Regeltechnik GmbH, 70719 Fellbach, Germany). By securing a positive pressure in the central column and a slightly negative pressure in the outer cylinder, which encloses the entire animal holder, air leaks from nose to thorax rather than from thorax to nose and dilution of test atmosphere at the nose of the animals is prevented.

TEST ATMOSPHERE
- Brief description of analytical method used: The actual concentration (by weight) of the non-volatile particles present in the test atmosphere was determined approximately once each hour by means of gravimetric analysis. Representative test atmosphere samples were obtained by passing approximately 5 L test atmosphere at 5 L/min through fibre glass filters (Schleicher and Schuell, GF10, Ø 47 mm). The nominal concentration was determined by dividing the total amount of test material used (by weighing) by the total volume of air passed through the exposure unit.
- Samples taken from breathing zone: yes

VEHICLE
- Composition of vehicle (if applicable): water
- Concentration of test material in vehicle (if applicable): 50 wt% GLDA in water
- Justification of choice of vehicle: based on good solubility in water
- Lot/batch no. (if required): no
- Purity: not applicable


TEST ATMOSPHERE (if not tabulated)
- Particle size distribution: During preliminary experiments, it was established that beyond a concentration of 4.3 g/m3, the particle size increased rapidly and the generation efficiency decreased. Therefore, 4.3 g/m3 was considered the technically highest attainable concentration, taking into account a respirable particle size, viz. a particle size distribution at 1-4 microns MMAD.
- MMAD (Mass Median Aerodynamic Diameter) / GSD (Geometric st. dev.):
at December 3: MMAD = 2.8 µm and GSD = 2.7
at December 4 (during exposure): MMAD = 2.8 µm and GSD = 2.7

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

Target concentration: 5 g/m3.
Actual concentration reached: 4.2 g/m3.
The actual concentration (by weight) was determined approximately once each hour by means of gravimetric analysis. Time weighed average concentration.

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The rats were visually inspected just before exposure, for reactions to treatment during the exposure,
shortly after exposure, and at least once daily during the observation period.
Body weights of the animals were recorded just before exposure (day 0), on day 7, and on day 14 prior to necropsy.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, gross pathological changes

Statistics:

Not required.

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 4.2 mg/L air (analytical)

Exp. duration:

4 h

Remarks on result:

other: limit test

Mortality:

None of the animals died during the study.

Clinical signs:

other: - During exposure: Although observation of the rats was limited during exposure due to the stay in restraining tubes, breathing at a decreased rate (graded as slight) was seen in all animals at all observation time points. - After exposure: Shortly after

Body weight:

Body weight gain during the observation period was as expected for animals of this age and strain.

Gross pathology:

No macroscopic abnormalities were observed at necropsy.

The nominal concentration of GLDA-Na4, calculated from the test material flow and the air flow was 33.3 g/m3 (66.6 g/m3 solution of 50 wt% GLDA-Na4), indicating a generation efficiency of 13%.

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information

Conclusions:

The acute inhalation LC50 of GLDA-Na4 was determined to be greater than 4.2 mg/L in males and females; this was the technically highest attainable concentration. As no mortality occurred at this concentration, no classification is needed according to OECD-GHS.

Executive summary:

GLDA-Na4 was evaluated for its acute inhalation toxicity potential in rats. The study was performed in accordance with OECD Guideline 403 (Acute Inhalation Toxicity). The study was designed and performed according to Good Laboratory Practice Standards. Five males and five females were exposed for four hours to an aerosol generated from the test material at a target concentration of 5 g/m3. A concentration of ca. 4.3 g/m3 was considered the technically highest attainable concentration, taking into account a respirable particle size (MMAD between 1 and 4 micron). The actual concentration of the test compound turned out to be 4.2 g/m3; the MMAD was 2.8 micron and gsd was 2.7. There was no mortality during the study. Clinical signs included slightly decreased breathing rate during exposure and a soiled fur of the head, neck, back, and/or abdomen shortly after exposure, which were no longer evident on Day 2. Sniffing was noticed in 4 animals shortly after exposure, in 7 animals on day 1 and in 1 animal on day 2. A discharge from the eyes was seen in a single animal on day 1. No other abnormalities were observed in the 14-day observation period. Body weight gain was as expected for animals of this age and strain and no macroscopic abnormalities were found.

The acute (4 -h) inhalation LC₅₀ of GLDA-Na4 was determined to be greater than 4.2 mg/L in males and females. This was the technically highest attainable concentration. As no mortality occurred at this concentration, no classification is needed according to OECD-GHS.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

One well performed and reported study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to standard protocol and under GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

Occlusive application

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Qualifier:

according to guideline

Guideline:

other: JMAFF Guidelines (2000)

Principles of method if other than guideline:

Principles other than OECD Guideline:
- Occlusive application

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld
- Age at study initiation: Young adult animals (approx. 8-9 weeks old)
- Weight at study initiation: Weight variation did not exceed ± 20% of the sex mean
- Fasting period before study: Not applicable
- Housing: Individually housed
- Diet (e.g. ad libitum): ad lib (rodent diet)
- Water (e.g. ad libitum): ad lib (tap water)
- Acclimation period: At least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.0 ± 3.0°C (actual range: 19.8-21.2°C)
- Humidity (%): 30-70% (actual range: 43-72%)
- Air changes (per hr): Approximately 15
- Photoperiod (hrs dark / hrs light): 12 hours artificial fluorescent light and 12 hours darkness per day


IN-LIFE DATES: From: October 9, 2008 To: October 29, 2008

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: Approx. 25 cm2 for males and 18 cm2 for females, on the back of the animal
- % coverage: Approx. 10%
- Type of wrap if used: Dressing consisting of a surgical gauze patch (Surgy 1D), successively covered with aluminum foil and Coban elastic bandage. For fixation of the bandages in females: Micropore tape


REMOVAL OF TEST SUBSTANCE
- Washing (if done): Skin was cleaned of residual test substance using tap water
- Time after start of exposure: 24h


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg (10 mL/kg) body weight
- Concentration (if solution): 200 mg/ml
- Constant volume or concentration used: yes, constant dosage volume in terms of mL/kg BW
- For solids, paste formed: no, test substance was dosed using a formulation


VEHICLE
- Amount(s) applied (volume or weight with unit): 200 mg/ml water
- Concentration (if solution): No info
- Lot/batch no. (if required): Water, Elix, Millipore S.A.S., Molsheim, France
- Purity: No info

Duration of exposure:

24 hours

Doses:

Single dosage: 2000 mg/kg

No. of animals per sex per dose:

5
Based on the available information the study was performed in a stepwise manner. Initially 3 animals were treated at 2000 mglkg. After
examination of the local effects at t=24 h, it was considered that treatment of the remaining animals (2 females and 5 males) could be performed at
the same dose level.

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
Weight: on Days 1 (pre-administration), 8 and 15
Clinical signs: At periodic intervals on the day of dosing (Day 1) and once daily thereafter, until Day 15. The time of onset, degree and duration
were recorded and the symptoms graded according to fixed scales:
Maximum grade 4: grading slight (1) to very severe (4)
Maximum grade 3: grading slight (1) to severe (3)
Maximum grade 1: presence is scored (1)
Mortality/Viability: Twice daily
- Necropsy of survivors performed: yes
- Other examinations performed: Internal macroscopic abnormalities

Statistics:

No statistics needed

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No mortality occurred.

Clinical signs:

other: Flat and/or hunched posture, piloerection and/or slight chromodacryorrhoea were noted in all animals. These signs were seen from Day 1 up to and including Day 4. Slight scales and/or scabs were seen in the treated skin-area of 4 females. These signs were

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Other findings:

No.

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information

Conclusions:

The acute dermal LD50 of GLDA-Na4, applied to the skin for 24 hours, is greater than 2000 mg/kg bw. Although higher concentrations than 2000 mg/kg have not been tested, but based on the absence of other changes than local, reversible, dermal changes at 2000 mg/kg bw, the test material was not classified according to OECD-GHS.

Executive summary:

A formulation of GLDA-Na4 was evaluated for its acute dermal toxicity potential in Wistar rats. The study is equivalent to the OECD Guideline 402 (Acute Dermal Toxicity). The study was designed and performed according to Good Laboratory Practice Standards. For 24 hours, 2000 mg/kg bw test substance is applied to the skin of ten rats (5 males and 5 females). The occluded application of the test material produced flat and/or hunched posture, piloerection and/or chromodacryorrhoea in all animals. These signs were seen from Day 1 up to and including Day 4. Scales and/or scabs were seen in the treated skin-area of 4 females. These signs were observed from Day 3 up to and including Day 9. No mortality occurred. Body weight gain in males and females was within the range expected for rats of this strain and age used in this type of study. The gross necropsy showed no significant gross changes. The acute dermal LD₅₀of GLDA-Na4, applied to the skin for 24 hours, is greater than 2000 mg/kg bw. Although higher concentrations than 2000 mg/kg have not been tested, but based on the absence of other changes than local, reversible, dermal changes at 2000 mg/kg bw, the test material was not classified according to OECD-GHS.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

One well performed and reported study available

Additional information

GLDA-Na4 is considered not to have significant acute oral, dermal and respiratory toxicity. The oral LD50 value in rats was in excess of 2000 mg/kg bw. No clinical signs of toxicity were noted at the level of 2000 mg/kg bw. All animals showed expected gains in body weight over the study period and no abnormalities were noted at necropsy.

The dermal LD50 of GLDA-Na4 in rats was in excess of 2000 mg/kg bw. Clinical signs of toxicity at that level consisted of flat and/or hunched posture, piloerection and/or chromodacryorrhoea, scales and/or scabs on the treated skin; the latter changes had disappeared by day 10. All animals showed expected gains in bodyweight over the study period and no abnormalities were noted at necropsy.

The 4 -hour LC50 of GLDA-Na4 is above 4200 mg/m3 for male and female rats; this was the technically highest attainable concentration still maintaining a respirable particle size (MMAD 2.8 µm; gsd 2.7). Clinical signs of toxicity consisted of a slightly decreased breathing rate, soiled fur of the head, neck, back and/or abdomen, sniffing, and discharge from the eyes. These changes had disappeared by day 3. Body weight gain was as expected for animals of this age and strain and no macroscopic abnormalities were found at necropsy.

Justification for selection of acute toxicity – oral endpoint

Well performed and reported study

Justification for selection of acute toxicity – inhalation endpoint

Well performed and reported study

Justification for selection of acute toxicity – dermal endpoint

Well performed and reported study

Justification for classification or non-classification

Based on the data indicated above, no classification for acute toxicity of GLDA-Na4 is needed. Although the acute oral toxicity test was carried out at a limit concentration of 2000 mg/kg bw, no toxicity was seen at this level, and therefore no classification in category V (GHS) would be needed. In addition, the absence of toxicity was confirmed in a separate study in mice (in vivo micronucleus test) in which no mortality was observed at levels of 2500 and 5000 mg/kg bw. This also holds for acute dermal toxicity, as no mortality is anticpiated between 2000 and 5000 mg/kg bw. With regard to inhalation toxicity, only slight toxicity was observed at the technically highest attainable concentration of 4200 mg/m3.