Trisodium 2-(carboxylatomethyl(2-hydroxyethyl)amino)ethyliminodi(acetate)

Repeated dose toxicity: oral

Administrative data

Endpoint:

chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles For read-across justification refer to section 13.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Materials and methods

Principles of method if other than guideline:

A bioassay for possible carcinogenicity was conducted by administering the test material in feed to Fischer 344 rats. The chemical was administered to 50 males and 50 females at low and high concentrations, for 103 weeks. Matched-control groups were composed of 20 males and 20 females. Animals were analysed for mortality, clinical signs, histopathological as well as gross pathological changes.

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Trisodium hydrogen ethylenediaminetetraacetate

EC Number:

205-758-8

EC Name:

Trisodium hydrogen ethylenediaminetetraacetate

Cas Number:

150-38-9

Molecular formula:

C10H16N2O8.3Na

IUPAC Name:

trisodium hydrogen 2,2',2'',2'''-(ethane-1,2-diyldinitrilo)tetraacetate

Details on test material:

- Name of test material: Trisodium EDTA
- Molecular formula (if other than submission substance): C10 H13 N2 O8 Na3
- Molecular weight (if other than submission substance): 358.19
- Smiles notation (if other than submission substance): OC(=O)CN(CCN(CC(=O)(O[Na]))CC(=O)(O[Na]))CC(=O)(O[Na])
- InChl (if other than submission substance): InChI=1S/C10H16N2O8.3Na/c13-7(14)3-11(4-8(15)16)1-2-12(5-9(17)18)6-10(19) 20;;;/h1-6H2,(H,13,14)(H,15,16)(H,17,18)(H,19,20);;;/q;3*+1/p-3
- Structural formula attached as image file (if other than submission substance): see Fig. 150-38-9 Structure.png

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Schmidt, Madison, Wisconsin, USA
- Weight at study initiation: 85-110 g
- Age at study initiation: 28 days
- Housing: four per cage in solid polycarbonate cages
- Diet: prepared from Wayne Lab Blox Meal (Allied Mills, Inc.) ad libitum
- Water: acidulated water ad libitum
- Acclimation period: 14 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-25°C
- Humidity (%): 45-55%
- Air changes (per hr): 15 times per hour
- Photoperiod (hrs dark / hrs light): 16/8

Administration / exposure

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): 3 times/week
- Mixing appropriate amounts with (Type of food): Wayne Lab Blox Meal (Allied Mills, Inc.)
- Storage temperature of food: 4°C

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- Analyses were performed, using FDA methods to determine the efficiency of the mixing procedure and the stability of the test chemical in feed. Recoveries were found to be 90.3 + / -1.4% of the theoretical value at 7,500 ppm EDTA and 90.4 + / - 3.4% of the theoretical value at 3,750 ppm. It was concluded from these results that the preparations contained reasonably accurate concentrations of EDTA and were mixed homogeneously, and that the chemical was stable in feed for at least a week.

Duration of treatment / exposure:

103 weeks

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
250; 500 mg/kg bw/day (original data: 3,750 ppm 7,500 ppm; conversion according to EU risk assessment)
Basis:
nominal in diet

No. of animals per sex per dose:

50 (except for the control, which consisted of only 20 animals)

Control animals:

yes, plain diet

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: twice daily

BODY WEIGHT: Yes
- Time schedule for examinations: approximately once a month

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): No
OPHTHALMOSCOPIC EXAMINATION: No
HAEMATOLOGY: No
CLINICAL CHEMISTRY: No
URINALYSIS: No
NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes; all major organs, not specified but presumably all organs used for histopathology: skin, lymph nodes, mammary gland, salivary gland, bone marrow, trachea, lungs and bronchi, heart, thyroids, parathyroids, esophagus, stomach, small intestine, large intestine, liver, gallbladder, pancreas, spleen, kidneys, adrenals, urinary bladder, prostate or uterus, testis or ovary, brain, and pituitary.
HISTOPATHOLOGY: Yes;
skin, lymph nodes, mammary gland, salivary gland, bone marrow, trachea, lungs and bronchi, heart, thyroids, parathyroids, esophagus, stomach, small intestine, large intestine, liver, gallbladder, pancreas, spleen, kidneys, adrenals, urinary bladder, prostate or uterus, testis or ovary, brain, and pituitary.

Statistics:

- Statistical tests of differences in survival between groups are compared using the method of Cox (1972) for two groups and an extension of this method by Tarone (1975) for more than two groups.
- Statistical analysis of the incidence of tumors was made using the Fisher exact test (Cox, 1970) to compare a control group to a group of treated animals at each dose. In addition, the Armitage and Cochran test for linear trend in proportions, with continuity correction (Armitage, 1971), was used.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

MORTALITY
The male rats exhibited a negative dose-related trend in survival with the probability level of P = 0.103; the treated and control groups of male rats can thus be considered as comparable to each other in survival. The female rats also exhibited a negative dose-related trend in survival. Even though this effect was statistically significant, it is most likely a chance finding as treated animals did not exhibit any deviations from the control group in regard to clinical signs or pathology.

CLINICAL SIGNS
No significant signs were observed among test animals during the first year of the study. In the 6 months preceding termination of the test, corneal opacities, ascites, and urine stains, occurred in both treatment and control groups.

BODY WEIGHT AND WEIGHT GAIN
Average body weights of treated male and female rats were comparable to those of the matched controls throughout the study.

GOSS PATHOLOGY
Inflammatory and degenerative changes were observed in about the same frequency in all groups. These lesions appeared to be related to age and no to the administration of the chemical.

HISTOPATHOLOGY: NEOPLASTIC
The incidence of neoplasms was high in the reproductive and endocrine systems and lower in the hematopoietic, respiratory, integumentary, and digestive systems. No neoplasms were observed in the nervous, musculoskeletal, or urinary systems or in organs of special sense. A number of tumors occurred in other organ systems of both sexes, controls as well as treated animals. In some instances the incidence of tumors in the controls exceeded that of the treated animals. With the possible exception of endocrine tumors in the males, no clear association between the incidence of tumors, treatment, or sex could be established (see table 1 and 2).

Effect levels

Key result

Dose descriptor:

NOAEL

Effect level:

>= 500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed at highest tested dose

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Table 1: Analyses of the Incidence of Primary Tumors at Specific Sites in Male Rats Fed EDTA Trisodium Salt in the Diet

Morphology (p-value)	Control	250 mg/kg bw/day	500 mg/kg bw/day
Hematopoietic System: Leukemia, Malignant Lymphoma and Lymphocytic Leukemia	3/20 (n.s.)	4/50 (n.s.)	4/50 (n.s.)
Adrenal: Pheochromocytoma	2/20 (n.s.)	5/49 (n.s.)	4/50 (n.s.)
Thyroid: C-cell Adenoma	0/17 (n.s.)	6/45 (p = 0 0.08)	3/38 (n.s.)
Pituitary: Chromophobe Adenoma	0/18 (p = 0.089)	3/47 (n.s.)	5/44 (n.s.)
Lung: Alveolar/Bronchiolar Adenoma and Carcinoma	1/18 (n.s.)	2/50 (n.s.)	3/49 (n.s.)
Liver: Hepatocellular Adenoma and Neoplastic Nodule	0/20 (n.s.)	1/48 (n.s.)	1/50 (n.s.)
Testis: Interstitial-cell Tumor	19/20 (n.s.)	43/50 (n.s.)	44/50 (n.s.)

Table 2 Analyses of the Incidence of Primary Tumors at Specific Sites in Female Rats Fed EDTA Trisodium Salt in the Diet

Morphology (p-value)	Control	250 mg/kg bw/day	500 mg/kg bw/day
Hematopoietic System: Leukemia, Malignant Lymphoma and Lymphocytic Leukemia	1/20 (n.s.)	8/50 (n.s.)	0/50 (n.s.)
Adrenal: Pheochromocytoma	1/20 (n.s.)	1/49 (n.s.)	1/48 (n.s.)
Thyroid: C-cell Adenoma	0/11 (n.s.)	0/36 (n.s.)	1/37 (n.s.)
Pituitary: Chromophobe Adenoma	6/19 (n.s.)	10/48 (n.s.)	11/50 (n.s.)
Lung: Alveolar/Bronchiolar Adenoma and Carcinoma	0/20 (n.s.)	3/48 (n.s.)	2/48 (n.s.)
Liver: Neoplastic Nodule	0/20 (n.s.)	1/48 (n.s.)	0/48 (n.s.)
Uterus: Endometrial Stromal Polyp	5/20 (n.s.)	6/50 (n.s.)	7/50 (n.s.)
Mammary Gland: Fibroadenoma	4/20 (n.s.)	3/50 (n.s.)	3/50 (n.s.)

Applicant's summary and conclusion

Conclusions:

The NOAEL following 103 weeks dietary exposure was 500 mg/kg/day

Executive summary:

The NOAEL following 103 weeks dietary exposure was 500 mg/kg/day