Edetic acid

Endpoint summary

Description of key information

There are no repeated dose studies with edetic acid available. However, under physiological conditions (pH 7-9) any EDTA salt as well as edetic acid will dissociate into the sodium cations and the respective anionic species of edetic acid depending on the dissociation equilibrium of edetic acid. Under the assumption of this equivalence it is likely that all EDTA salt chelate ions in vivo. A 90-day (Na2EDTA) as well as a 2-year (Na3EDTA) feeding study on rats provide reliable toxicological information for an overall NOAEL of about 500 mg/kg bw. A NOAEC value of 3 mg/m³ air was established in a subchronic toxicity study with Na2H2EDTA.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

A bioassay for possible carcinogenicity was conducted by administering the test material in feed to B6C3F1 mice. 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

Species:

mouse

Strain:

B6C3F1

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Wilmington, USA
- Weight at study initiation: 19-22 g
- Age at study initiation: 28 days
- Housing: five 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

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): 2 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

Dose / conc.:

3 750 ppm

Remarks:

469 mg/kg bw/day
(conversion factor according to EU risk assessment)

Dose / conc.:

7 500 ppm

Remarks:

938 mg/kg bw/day
(conversion factor according to EU risk assessment)

No. of animals per sex per dose:

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

Control animals:

yes, plain diet

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

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.

Details on results:

MORTALITY
No statistically significant difference in survival between the different groups in both sexes. (males: 5/50 (10%) of the low-dose group, 2/50 (4%) of the high-dose group, and 1/20 (5%) of the control; females: 0/50 low-dose female mice, 1/20 (5%) of the control group and 3/50 (6%) of the high-dose group)

CLINICAL SIGNS
Ataxia occurred in a low-dose male at 8 months, and ascites was noted in mice of both sexes during the second year of the study.

BODY WEIGHT AND WEIGHT GAIN
In male mice only the high-dose group showed throughout most of the test period a decrease in average body weight compared to the controls. In female mice average body weights of the treatment groups were depressed in a dose-related manner during the test period, although the effect was small. No individual data given. No information whether this effect is statistically relevant is available.

GROSS PATHOLOGY
Nothing reported.

HISTOPATHOLOGY: NEOPLASTIC
A variety of neoplasms was observed in both treated and control animals. Each type observed has been encountered previously as a spontaneous lesion in the mouse. However, the incidence of neoplasms in all groups was high in the hematopoietic, endocrine, digestive, and respiratory systems. The incidence of neoplasms in other systems was variable. (See table 1 and 2 below)

Dose descriptor:

NOAEL

Effect level:

>= 938 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical signs

gross pathology

histopathology: non-neoplastic

mortality

Critical effects observed:

not specified

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

Morphology (p-value)	Control	625 mg/kg bw/day	1250 mg/kg bw/day
Hematopoietic System:  Malignant Lymphoma	2/20 (n.s.)	7/46 (n.s.)	7/48 (n.s.)
Thyroid: C-cell Adenoma	0/10 (n.s.)	1/29 (n.s.)	1/33 (n.s.)
Pituitary: Chromophobe Adenoma	1/13 (n.s.)	0/19 (n.s.)	1/26 (n.s.)
Lung: Alveolar/Bronchiolar Adenoma and Carcinoma	2/18 (0.096)	2/50 (n.s.)	3/49 (n.s.)
Liver: Hepatocellular Adenoma and Neoplastic Nodule	3/19 (n.s.)	10/44 (n.s.)	10/47 (n.s.)

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

Morphology (p-value)	Control	625 mg/kg bw/day	1250 mg/kg bw/day
Hematopoietic System:  Malignant Lymphoma	5/19 (n.s.)	11/49 (n.s.)	12/47 (n.s.)
Thyroid: C-cell Adenoma	1/12 (n.s.)	3/33 (n.s.)	1/34 (n.s.)
Pituitary: Chromophobe Adenoma	2/12 (n.s.)	6/34 (n.s.)	4/29 (n.s.)
Lung: Alveolar/Bronchiolar Adenoma and Carcinoma	0/19 (n.s.)	3/47 (n.s.)	3/49 (n.s.)
Liver: Hepatocellular Adenoma and Neoplastic Nodule	0/19 (n.s.)	1/46 (n.s.)	1/47 (n.s.)

Reference 2

Endpoint:

chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

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

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

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

Dose / conc.:

3 750 ppm

Remarks:

approx. 250 mg/kg bw/day (conversion according to EU risk assessment)
Basis: nominal in diet

Dose / conc.:

7 500 ppm

Remarks:

approx. 500 mg/kg bw/day (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

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.

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 below).

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical signs

gross pathology

histopathology: neoplastic

mortality

Remarks on result:

other: Highest dose tested

Critical effects observed:

not specified

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.)

Reference 3

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

A 13 weeks feeding study on rats was performed using 3 different dose groups and one control group. After 13 weeks 50% of the animals of each group were sacrificed and tissues examined for gross and histopathologic changes. The remaining animals were placed on control diet for 4 weeks. Thereafter animals were sacrificed and examined for gross and histopathologic changes.

GLP compliance:

no

Species:

rat

Strain:

other: Holtzman

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 120 ± 6 g
- Diet: Ground Purina Laboratory Chow

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
The top level (10.0 % ) diet was prepared by adding the appropriate amount of Na2H2EDTA to the basic diet. This was then diluted with the basic diet to prepare the 5.0 % diet. Lower concentrations were similarly prepared by dilution of the next highest concentration.

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

daily

Dose / conc.:

500 mg/kg bw/day (nominal)

Remarks:

(original data: 1 %, conversion factor: 20)

Dose / conc.:

2 500 mg/kg bw/day (nominal)

Remarks:

(original data: 5 %, conversion factor: 20)

Dose / conc.:

5 000 mg/kg bw/day (nominal)

Remarks:

(original data: 10 %, conversion factor: 20)

No. of animals per sex per dose:

10

Control animals:

yes, plain diet

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION AND COMPOUND INTAKE :
- Mean food consumption g/animal

WATER CONSUMPTION
- not specified

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the end of the 4th and 13th week
- Parameters checked: hematocrit, hemoglobin, total and differential white blood cell counts, prothrombin times

CLINICAL CHEMISTRY
- Time schedule for collection of blood: at the end of the 4th and 13th week
- Parameters checked: calcium level

URINALYSIS: Yes
- Time schedule for collection of urine: not specified
- Parameters checked: Calcium

OPHTHALMOSCOPIC EXAMINATION: No
CLINICAL CHEMISTRY: No
NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: liver, kidney, spleen, lung, heart, urogenital system, digestive organs, and muscle
HISTOPATHOLOGY: Yes

Details on results:

CLINICAL SIGNS AND MORTALITY
500 mg/kg bw/day dose group: nothing abnormal detected
2500 mg/kg bw/day dose group: 2/10 animals died; diarrhea starting at the third day
5000 mg/kg bw/day dose group: 6/10 animals died; animals were emaciated, diarrhea starting at the third day

BODY WEIGHT GAIN
500 mg/kg bw/day dose group: no difference to the control group
2500; 5000 mg/kg bw/day dose group: statistically significant reduced body weight gain (control: 326 g; 2500 mg/kg bw/day dose group: 185 g; 5000 mg/kg bw/day dose group: 4 g)

FOOD CONSUMPTION AND COMPOUND INTAKE
500 mg/kg bw/day dose group: normal food consumption
2500; 5000 mg/kg bw/day dose group: statistically significant lower food consumption than the control

WATER CONSUMPTION
500 mg/kg bw/day dose group: nothing abnormal detected
2500 mg/kg bw/day dose group: twice the water consumption of the control
5000 mg/kg bw/day dose group: nothing abnormal detected

HAEMATOLOGY
after 4 weeks: hematocrits and hemoglobins of the 5000 mg/kg bw/day dose group slightly depressed
after 13 weeks: nothing abnormal detected in any of the groups

CLINICAL CHEMISTRY
serum calcium level did not differ from the control

URINALYSIS: total calcium
500 mg/kg bw/day dose group: no difference to the control
2500; 5000 mg/kg bw/day dose group: ca. twice as much as in the control

GROSS PATHOLOGY
500; 2500 mg/kg bw/day dose group: nothing abnormal detected
5000 mg/kg bw/day dose group: pale livers,

HISTOPATHOLOGY:
Nothing abnormal detected

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male

Basis for effect level:

body weight and weight gain

clinical signs

food consumption and compound intake

urinalysis

water consumption and compound intake

Critical effects observed:

not specified

Recovery:

Once the survivors were placed on a control diet the diarrhea, when present, subsided within 24 hours. The animal that had previously received 5000 mg/kg bw/day Na2H2EDTA still had low food consumption and died within 1 week. All other animals survived this 4-week period . The animals that had received 2500 mg/kg bw/ day Na2H2EDTA gained weight more slowly than did the other animals and weighed significantly less than controls at the end of the 4-week withdrawal period. The chelating agent was not detectable in the urine after 2-3 days, nor in the feces after 7 days. The autopsies revealed no significant findings.

- EGTA was better tolerated in the diet than EDTA

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

500 mg/kg bw/day

Study duration:

chronic

Species:

rat

Additional information

ORAL

A 90-day feeding study of Na2EDTA in rats revealed a NOAEL of 500 mg/kg bw (Wynn, 1970). Groups of 10 male Holzman rats received 1, 5 and 10% (respectively 500 mg/kg bw; 2,500 mg/kg bw and 5,000 mg/kg bw) Na2EDTA in the diet for 90 days. The mid and high dose animals expressed a significant decrease of body weights and food consumption. Dose dependent mortality was evident by 20% in the 5% and 60% in the 10% group. In these groups animals exhibited diarrhea and were emaciated. Water consumption was increased. In the upper dose there was an intermittent decrease of hematocrite and hemoglobin levels, livers appeared to be pale. Histological investigation failed to reveal any pathological alteration. From this investigation, a NOAEL of 500 mg/kg/day equivalent to 1% in diet can be deduced for male rats. It should be noted that in this study no complete clinical biochemistry has been performed as required by the OECD 408 guideline.

A two year feeding study with (Na3EDTA x 3H2O) to rats revealed a NOAEL of 500 mg/kg/day (corresponding to 7,500 ppm in the diet) (NTIS, 1977). In this feeding study with two dose levels 3,750 ppm and 7,500 ppm (corresponding to approximately 250 and 500 mg/kg/day) no substance related toxic effects could be observed.

The same study at the same dose levels (3,750 ppm and 7,500 ppm; corresponding to approximately 469 and 938 mg/kg/day) conducted with mice showed a NOAEL of 938 mg/kg bw/day. There were also no treatment related changes.

An one month feeding study of Na2EDTA in rats revealed a NOAEL of 1,125 mg/kg bw (this corresponds to 2.25% in the diet) (Kawamata, 1980). In this study test substance was incorporated at levels of 1, 2.25 and 5% in the diet (this corresponds to 500, 1125 and 2500 mg/kg bw). 15 rats per sex and dose level were exposed over a period of one month. At the upper dose level body weight decrease, some mortalities and a reduction of total leucocytes and lymphocytes as well as an increase of bound urine nitrogen (BUN) and a decrease Ca serum levels were found. Pathological investigation at this dose level revealed a decrease of liver, spleen and thymus weight. Some parakeratosis was detected in the oesophagus and forestomach by histopathology.

 

INHALATION

In a subacute repeated dose toxicity study (BASF SE, 2009) 10 male Wistar rats per concentration were exposed to a respirable dust aerosol of Na2H2EDTA for 6 hours per day for 5 consecutive days at concentrations of 0, 30, 300, 1000 mg/m³ air.

Exposure in the high dose group (1000 mg/m³) was for one day only, due to mortality observed. Inhalation exposure to 1000 mg/m³ disodium EDTA for 6 hours caused lethality in 6 out of 20 male rats. Histological examination of the lung of the dead rats revealed congestion, edema, multifocal hemorrhages and inflammatory cell infiltrates.

Inhalation exposure of rats to Na2H2EDTA for 6 hours per day, 5 consecutive days caused concentration-dependent lesions in the larynx and lungs that were fully reversible within 14 days. Due to histopathological changes in the low dose group a No-Observed-Adverse-Effect-Concentration could not be determined. The LOAEC was considered to be 30 mg/m³ air.

The study was planned as range finder study and conducted according to OECD Guideline 412.

In a subchronic repeated dose toxicity study (BASF SE, 2014) according to OECD guideline No. 413 Wistar rats were exposed to a respirable dust aerosol of Na2H2EDTA for 6h/d on 5 consecutive d/w for 13 weeks (65 exposures in total) at concentrations of 0, 0.5, 3, 15 mg/m3 air.

Inhalation exposure of rats to Na2H2EDTA did not lead to any substance-related clinical signs of toxicity. Nor were there any effect in clinical chemistry, hematology. Histological examination revealed some effects in larynx at the highest tested concentration of 15 mg/m³. No signs of systemic toxicity were observed up to a concentration of 15 mg/m³.

Signs of local toxicity were observed only at the high concentration of 15 mg/m³. Under the current test conditions, the No Observed Adverse Effect Concentration (NOAEC) for local effect in larynx was 3 mg/m³, the NOEC for systemic effect is 15 mg/m³.

The local key effect of respirable Na2H2EDTA in the respiratory tract (larynx) is assumed to be mainly concentration-related, hence the impact of exposure time should be low at subcritical concentrations, which was confirmed by the 90-day study: although the number of exposures was factor 13 higher than in the 5-day dose-range-finder study, the local effects at 15 mg/m³ in the subchronic inhalation study were mild compared to the 5-day dose-range-finder study that showed a more severe effect at 30 mg/m³.

It is justified to classify H4EDTA for repeated dose effects due to its analogue substance Na2H2EDTA that induced local effects at low concentrations and the potential human relevance of the effects. However, due to the low severity and incidence of the effects at 15 mg/m³ in the subchronic toxicity study and the reversibility of the local effects, a STOT RE Cat.2 (H373) is considered sufficiently conservative.

Justification for classification or non-classification

SELF-CLASSIFICATION ACCORDING TO REGULATION (EC) No 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. As a result, the test susbstance is considered to be classified as STOT RE Cat 2, H373 (May cause damage to organs through prolonged or repeated exposure) under Regulation (EC) No 1272/2008, as amended for the ninth time in Regulation (EU) No 2016/1179.

CLASSIFICATION ACCORDING TO ANNEX VI OF REGULATION (EC) No 1272/2008.
The test substance is not officially classified for repeated dose toxicity according to Regulation (EC) No 1272/2008, as amended fot the ninth time in Regulation (EU) No 2016/1179.