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

Acute Toxicity: dermal

Administrative data

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.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

Occlusive application

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Test guideline 4

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

Test material

Test material information

Constituent 1

Reference substance name:

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

EC Number:

257-573-7

EC Name:

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

Cas Number:

51981-21-6

Molecular formula:

C9H9NO8Na4

IUPAC Name:

tetrasodium 2-[bis(carboxylatomethyl)amino]pentanedioate

Details on test material:

- Name of test material (as cited in study report): GLDA
- Molecular formula (if other than submission substance): C9H9NO8.Na4
- Molecular weight (if other than submission substance): 351.13
- Physical state: White powder
- Analytical purity: See 'Confidential details on test material'
- Purity test date: June 23, 2008
- Lot/batch No.: CFC-8839 (see CoA in the report attached)
- Expiration date of the lot/batch: June 23, 2010
- Stability under test conditions: in water at least 96 hours stable, stable under storage conditions
- Storage condition of test material: at room temperature in the dark
- Other: solubility in water is approximately 1000 g/L; pH 10-12
- Analytical purity / Composition of test material, percentage of components: 91.0 ± 0.5 wt% (Assay as GLDA-Na4)

Test animals

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

Administration / exposure

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

Results and discussion

Effect levels

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.

Applicant's summary and conclusion

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.