N-carbamoylmethyliminodi(acetic acid)

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-10-04 to 2016-10-26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

17th December 2001

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Version / remarks:

30th May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

N-carbamoylmethyliminodi(acetic acid)

EC Number:

247-530-0

EC Name:

N-carbamoylmethyliminodi(acetic acid)

Cas Number:

26239-55-4

Molecular formula:

C6H10N2O5

IUPAC Name:

2,2'-[(2-amino-2-oxoethyl)imino]diacetic acid

Test material form:

liquid

Test animals

Species:

rat

Strain:

Wistar

Remarks:

Crl:WI

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: TOXI COOP ZRT. Cserkesz u. 90., 1103 Budapest, Hungary
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 8 weeks old in first and second step, 9 weeks old in third and fourth step
- Weight at study initiation: 188 - 193 g in first, 189 - 194 g in second step, 196 - 211 g in third and 194 - 196 g in fourth step
- Fasting period before study: 1 day
- Housing: group caging (3 rats/cage), Type II polypropylene/polycarbonate cages
- Diet: ad libitum, ssniff® SM R/M-Z+H complete diet for rats and mice produced by ssniff Spezialdiäten GmbH, D-59494 Soest Germany
- Water: ad libitum, tap water
- Acclimation period: 5-12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+/-3
- Humidity (%): 30 - 70
- Air changes (per hr): approx. 10
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 and 30 mg/mL
- Amount of vehicle: 10 mL/kg bw
- Justification for choice of vehicle: standard vehicle
- Purity: aqua purificata Ph.Hg. VIII. from Parma Produkt Kft. (Batch no. 1606-5508)

MAXIMUM DOSE VOLUME APPLIED: 2 mL

CLASS METHOD
- Rationale for the selection of the starting dose: The starting dose was selected on the basis of the available information about the test item and similar substances.

Doses:

300 and 2000 mg/kg bw

No. of animals per sex per dose:

6 females (each 3 per step)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed individually after dosing at least once during the first 30 minutes, then 1 h, 2 h, 3 h, 4 h, after the treatment and once each day for 14 days thereafter. The body weights were recorded on day 0 (just before the treatment), on day 4, on day 5, on day 7, on day 8 and on day 15 with a precision of 1 g.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, appearance of tissue and organs
- Experimental design: stepwise procedure with two groups with 3 rats each per dose

Statistics:

not applicable

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Mortality:

2000 mg/kg bw: 5 of 6 (one rat each on days 4, 7, 8 and 2 rats on day 5)
300 mg/kg bw: 0 of 6

Clinical signs:

Group 1 treated with 2000 mg/kg bw (observed in two rats between day 3 and day 6):
- decreased activity (5 cases of 39 observations)
- abnormal gait (5/39)
- pilorection (5/39)
- decreased body tone (4/39)
- dyspnoea (2/39, observed in one rat only)

Group 2 treated with 2000 mg/kg bw (observed in one or two rats between day 3 and day 8):
- decreased activity (10 cases of 31 observations)
- pain reaction (2/31)
- vocalisation (3/31)
- tremor (2/31)
- abnormal gait (6/31)
- pilorection (9/31)
- decreased body tone (9/31)
- closed eyes (2/31)
- dyspnoea (7/31)
- prone position (1/31)
- diarrhea (3/31)
- decreased body temperature (1/31)
- incoordination (1/31)

Group 3 and 4 treated with 300 mg/kg bw: no symptoms

Body weight:

The mean body weight and body weight gain data of group 1 and group 2 (2000 mg/kg bw) could not be evaluated, because of mortalities. A body weight loss was observed in one female treated with 2000 mg/kg bw dose between treatment day and Day 7. This body weight loss was approx. 29.6 %.
The body weight and body weight gain data of survivor animal treated with 2000 mg/kg bw (group 1) and animals of 300 mg/kg bw dose (group 3 and 4) corresponded to their species and age throughout the study.

Gross pathology:

Group 1 treated with 2000 mg/kg bw:
In one rat, pale and enlarged kidneys, yellowish-white renal cortex, dark red medullary substance in the kidney and a decreased spleen were observed.
In another rat autolysis was observed (due to death) and no changes were observed in the third rat.
All observations were related to the test substance.

Group 2 treated with 2000 mg/kg bw:
In all rats, pale and enlarged kidneys and decreased and pale spleens were observed.
In two rats, yellowish-white renal cortexes, dark red medullary substance in the kidneys, dark red lungs and marked dark livers were found.
Decreased lymph node in the colon was found in one rat.
All observations were related to the test substance.

In both groups 3 and 4 treated with 300 mg/kg bw one rat hydrometra was observed, a physiological finding related to the cycle. In group 4, the same rat had pale kidneys, which was considered as an individual variation not related to the test substance.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

The LD50 of the test item is between 300 and 2000 mg/kg body weight by oral route in the rat.

Executive summary:

A study according to OECD 423 was conducted to assess the toxicity of test item when administered in a single dose to rats at one or more defined dose levels. The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats. As all animals survived on Day 1, three further female rats were treated with the same (2000 mg/kg bw) dose. Since half of the animals (i.e. 3 out of 6 rats) died within one week, the test was continued at 300 mg/kg bw dose level on two further groups (three female rats each). Two more animals died at 2000 mg/kg bw thereafter. No animal died at 300 mg/kg bw, so the test was finished, the stopping criteria of Annex 2d of OECD Guideline No. 423 was met. Animals were weighed, observed for lethality and toxic symptoms for 14 days after the treatment. Gross pathological examination was carried out in all animals. Five of six rats dosed at 2000 mg/kg bw died between Day 4 and Day 8. No death occurred at 300 mg/kg bw single oral dose of the test item until the end of the 14-day observation period. Clinical symptoms like CNS symptoms, disturbances of coordination and the autonomic functions were observed in 5 out of 6 animals at 2000 mg/kg bw between Day 3 and Day 8. No clinical symptoms were observed at 300 mg/kg bw on the day of the treatment and during the 14-day observation period, the general state and behaviour of experimental animals were normal. Body weight loss was observed in one female at 2000 mg/kg bw in the first week. It was considered as a toxic effect of the test item. The body weight development was inconspicuous in all surviving animals at 300 and 2000 mg/kg bw. The macroscopic external necropsy findings as piloerection, emaciation, blood around the nose and mark of faeces around the rectum were found in 2000 mg/kg bw dose. Macroscopic internal changes were manifested in following organs: kidney, stomach, spleen, colon, lung and liver. These alterations were related to the effect of the test item. All organs of the animals treated with 300 mg/kg bw dose proved to be free of treatment related gross pathological changes. In conclusion, the LD50 of the test item is between 300 and 2000 mg/kg body weight by oral route in the rat.