Disodium dihydrogen ethylenediaminetetraacetate

Endpoint summary

Description of key information

The acute oral LD50 of Na2EDTA is 2800 mg/kg bw (BASF SE, 1973).

The LOAEC established in an inhalation study with Na2EDTAwas considered to be 30 mg/m³ air.

Furthermore, it is highly unlikely that EDTA induced acute dermal toxicity as neither Ca or Na salts of EDTA are able to penetrate the skin.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to OECD 401 guideline study with acceptable restrictions [Body weight was only determined at the beginning of the study (OECD: weekly); Observation period: 7 days (OECD:14 days)]

Principles of method if other than guideline:

BASF-TEST: In principle, the methods described in the OECD Guideline 401 were used. Young adult laboratory rats were purchased from breeder. Usually the source and strain of animals were not documented. Several groups of 5 rats per sex and dose were treated simultaneously by gavage with preparations of the test substance in suitable vehicle. The concentrations of these preparations were used to achieve comparable volumes per kg body weight. Group-wise documentation of clinical signs was performed over the 7 day study period. Body weight was determined before the start of the study only, as it was needed for determination of dose

GLP compliance:

no

Test type:

standard acute method

Species:

rat

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Mean body weight at study initiation:
259 g males/ 211 g females

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

DOSAGE PREPARATION:
- Stock solutions prepared: 30 %
- Dose volume applied: 2500 mg/kg bw dose group:
8.33 mL/kg bw
3200 mg/kg bw dose group: 10.66 mL/kg bw
4000 mg/kg bw dose group: 13.33 mL/kg bw
5000 mg/kg bw dose group: 16.66 mL/kg bw
6400 mg/kg bw dose group: 21.4 mL/kg bw

Doses:

2500; 3200; 4000; 5000; 6400 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 7 days;
- The animals were observed for mortality and clinical signs of toxicity;
- Frequency of observations: Several times on the application day, thereafter once each working day;
- Body weights were only recorded at the beginning of the study;
- Necropsy of survivors and animals which died performed: yes

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 800 mg/kg bw

Mortality:

- One female died in the 2500 mg/kg bw dose group; 9/10 animals died in the 3200 mg/kg bw dose group and all animals of the higher dose groups (see "Any other information on results incl. tables").

Clinical signs:

other: - 2500, 3200 and 4000 mg/kg bw: directly after application: accelerated respiration, squatting posture, twitching, ataxia, red eyes, some animals showed light secretion, reluctance to move; the next day: squatting posture, contaminated fur, intermittened

Gross pathology:

Animals which died:
- heart: acute dilatation, venous hyperemia
- liver: congestion
- gut: diarrhea like content
- stomach: dilatation
- kidneys: degeneration
Animals which were sacrificed:
- nothing abnormal detected

Table 1: Mortalities of rats after oral application

		2500 mg/kg bw	3200 mg/kg bw	4000 mg/kg bw	5000 mg/kg bw	6400 mg/kg bw
1 h	male	0/5	0/5	0/5	0/5	0/5
	female	0/5	0/5	0/5	0/5	0/5
24 h	male	0/5	3/5	5/5	5/5	5/5
	female	1/5	5/5	5/5	5/5	5/5
48 h	male	0/5	3/5	5/5	5/5	5/5
	female	1/5	5/5	5/5	5/5	5/5
7 d	male	0/5	4/5	5/5	5/5	5/5
	female	1/5	5/5	5/5	5/5	5/5

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Documentation insufficient for assessment

Principles of method if other than guideline:

Test solutions were administered orally, after 15 hours of food deprivation. Clinical signs and symptoms were monitored during the experimental period . Animals were given regular laboratory chow 6 hr after a single administration by various routes and the number of dead animals were counted until the 14th day. Anatomical examination was performed immediately after death or at terminal sacrifice on day 14.

GLP compliance:

not specified

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Shizuoka Laboratory Animal Center
- Age at study initiation: 5 weeks
- Acclimation period: 1 week

Route of administration:

oral: gavage

Vehicle:

olive oil

Doses:

6 doses no further data availible

No. of animals per sex per dose:

10

Control animals:

not specified

Statistics:

The fifty percent of lethal dose (LD50) or lethal concentration (LC50) was calculated using the Litchfield and Wilcoxon method.

Sex:

male

Dose descriptor:

LD50

Effect level:

3 735 mg/kg bw

Sex:

female

Dose descriptor:

LD50

Effect level:

3 690 mg/kg bw

Clinical signs:

other: ataxia, convulsions, diarrhea

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 800 mg/kg bw

Quality of whole database:

Comparable to OECD 401 guideline study

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 412 (Repeated Dose Inhalation Toxicity: 28/14-Day)

Deviations:

yes

Remarks:

Dosing until day 5 only

GLP compliance:

yes (incl. QA statement)

Test type:

other: subacute

Limit test:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Batch No. of test material: 06088797V0

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Expiry date: 1 September 2011

Species:

rat

Strain:

Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

Age: 7 weeks (approx.)
Identification: Tattooing of ears
All animals free of disease and clinical signs
Rats housed together (5 animals per cage) in Polysulfon cages
Bedding: Type Lignocel fibres, dust free bedding
Wooden gnawing blocks for enrichment
Rooms: Fully ariconditioned, temperature range 20 to 24 degrees celcius, 30 to 70 % humidity
Light/dark cycle of 12 hours (6 am to 6 pm light, 6 pm to 6 am dark)
Food, drinking water and bedding/enrichment materials were analysed for chemical and microbiological contaminants.

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

air

Details on inhalation exposure:

A dust aerosol was generated using a dust generator and compressed air inside a mixing stage mixed with conditioned dilution air and passed into the inhalation system. The test substance was mixed with Aerosil R972 prior to facilitate aerosol generation.

Analytical verification of test atmosphere concentrations:

yes

Remarks:

Concentrations of the inhalation atmospheres were analyzed using gravimetry. Daily means were calculated based on 2 measured samples per concentration and exposure. From the Daily mean values of each concentration, mean concentrations and standard deviati

Duration of exposure:

6 h

Remarks on duration:

per day, 5 consecutive days

Concentrations:

- 30, 300, 1000 mg/m³ (nominal conc. of Na2H2EDTA)
- 33.3 (± 2.3), 320 (± 27), 1103 (± 52) mg/m³ (measured (with SD) referring to test substance Na2H2EDTA × 2 H2O)

No. of animals per sex per dose:

10 animals per dose group
An additional 10 animals for the high dose group and control

Control animals:

yes

Details on study design:

The animals were exposed to a respirable dust aerosol for 6 hours per day for 5 consecutive days. The exception was the high dose group (1000 mg/m³) where exposure was for one day only due to mortality observed.

Statistics:

Body weight/body weight change, food consumption - comparison of each group with control using DUNNETTS test (two-sided) for the hypothesis of equal means
Clinical pathology, urine volumes, urine specific gravity, Weight parameters - Non-parametric one-way analysis using Kruskal-wallis test (two sided). If resulting p-value was less than 0.05, a pairwise comparison of each dose group with the control group was performed using Wilcoxon-test (two sided) for equal means.

Key result

Sex:

male

Dose descriptor:

other: LOAEC

Effect level:

ca. 30 mg/m³ air

Based on:

act. ingr.

Remarks:

Na2H2EDTA

Remarks on result:

other: Basis for effect level: histopathology of the respiratory tract and lung weights

Mortality:

6 deaths in the high dose group on days 0 and 1. Accelerated respiration, respiration sounds, piloerection, red encrusted nose, hunched position; Mid dose group - accelerated respiration, respiration sounds, piloerection, reduced fur care

Clinical signs:

other: 6 deaths in the high dose group on days 0 and 1. Accelerated respiration, respiration sounds, piloerection, red encrusted nose, hunched position; Mid dose group - accelerated respiration, respiration sounds, piloerection, reduced fur care

Body weight:

Decreased bodyweight change in mid and high dose group

Gross pathology:

Congestion, edema and multifocal hemorraghes in lungs of high dose group

Other findings:

FOOD CONSUMPTION
- decreased food consumption between days 0 and 1 in mid and high dose group

ORGAN WEIGHTS
- Lung weight increase in low and mid dose group

DETAILS ON RESULTS

Histopathology results:

High dose: Multifocal hemorraghes in the lungs; Inflammatory cell infiltrates

Mid dose:

Larynx: laryngeal, epithelial necrosis, multifocal, in various levels of the larynx

Inflammatory cell infiltrates in various levels of the larynx

laryngeal squamous metaplasia, multifocal, in various levels of the larynx

Regenerative hyperplasia of the laryngeal epithelium, multifocal, in various levels of the larynx

Lungs: Regenerative hyperplasia of bronchiolar epithelium (predominantly: medium bronchi, terminal bronchioles)

Mucous cell hyperplasia in large bronchi

interstitial infiltration of eosinophylic granulocytic cells

Low dose:

Larynx: Laryngeal, epithelial necrosis, multifocal, at the base of the epiglittis (level 1)

Inflammatory cell infiltrates at the base of the epiglottis (level 1)

Lungs: Regenerative hyperplasia of the bronchiolar epithelium (predominantly medium bronchi and terminal bronchioles)

Mucous cell hyperplasia in large bronchi

interstitial infiltration of eosinophylic granulocytic cells.

There were no histopathological findings in any of the recovery group animals. Thus all pathology was reversible within the recovery period.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Value:

30 mg/m³ air

Quality of whole database:

OECD TG 412

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

ORAL ROUTE

In the key study performed by BASF (1973) single doses of 2500, 3200, 4000, 5000 and 6400 mg/kg bw Na2EDTA were administered by gavage to male and female rats as 30 % solution in carboxymethyl cellulose solution. The dose groups consisted of 5 males and 5 females each and the animals were observed for 7 days. The LD 50 was found to be 2800 mg/kg bw. Clinical symptoms were accelerated respiration, squatting posture, contaminated fur, intermittened respiration, reluctance to move. Autopsy of animals which died revealed dilatation of the heart and stomach as well as diarrhoea like content in the gut, congestion of the liver and degeneration of the kidney. The animals which were sacrificed showed no abnormalities during necropsy.

In a poorly documented oral toxicity study on Wistar rats, an LD50 of 3735 mg/kg bw for males and 3690 mg/kg bw for females were reported. After the gavage application of Na2EDTA in olive oil ataxia, convulsions and diarrhoea were reported (Hasegawa, 1989).

 

INHALATION ROUTE

In a subacute repeated dose toxicity study (BASF SE, 2009) 10 male Wistar rats per dose 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 (also see chapter 7.5).

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 hemorraghes and inflammatory cell infiltrates.

Inhalation exposure of rats to disodium EDTA for 6 hours per day, 5 consecutive days cause concentration dependant 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 effect level could not be determined. The LOAEC was considered to be 30 mg/m³ air.

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. As a result, the substance is considered to be classified as Acute Toxicity Inhalation Cat. 4 (H332, harmful if inhaled) but not classified for acute oral and acute dermal toxicity under Regulation (EC) No 1272/2008, as amended for the tenth time in Regulation (EU) No 2017/776.