Guanidinium nitrate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984-02-29 to 1984-04-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Reference 2

Reference Type:

publication

Title:

Acute Oral Toxicity of Guanidine Nitrate

Author:

Korte D W et al

Year:

1993

Bibliographic source:

International Journal of Toxicology, Vol. 12, No. 6, p.594-595

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Health effects test guidelines, August 1982, EPA 560/6-82-001

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Guanidinium nitrate

EC Number:

208-060-1

EC Name:

Guanidinium nitrate

Cas Number:

506-93-4

Molecular formula:

CH6N4O3

IUPAC Name:

amino(imino)methanaminium nitrate

impurity 1

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

water

impurity 2

Reference substance name:

Ammonium nitrate

EC Number:

229-347-8

EC Name:

Ammonium nitrate

Cas Number:

6484-52-2

Molecular formula:

H3N.HNO3

IUPAC Name:

Ammonium nitrate

impurity 3

Reference substance name:

4,6-diamino-1,3,5-triazin-2(1H)-one

EC Number:

211-455-1

EC Name:

4,6-diamino-1,3,5-triazin-2(1H)-one

Cas Number:

645-92-1

Molecular formula:

C3H5N5O

IUPAC Name:

4,6-diamino-1,3,5-triazin-2(1H)-one

impurity 4

Reference substance name:

(4,6-Diamino-1,3,5-triazine-2-yl)guanidine

Cas Number:

4405-08-7

Molecular formula:

C4H8N8

IUPAC Name:

(4,6-Diamino-1,3,5-triazine-2-yl)guanidine

impurity 5

Reference substance name:

Melamine

EC Number:

203-615-4

EC Name:

Melamine

Cas Number:

108-78-1

Molecular formula:

C3H6N6

IUPAC Name:

1,3,5-triazine-2,4,6-triamine

impurity 6

Reference substance name:

Cyanoguanidine

EC Number:

207-312-8

EC Name:

Cyanoguanidine

Cas Number:

461-58-5

Molecular formula:

C2H4N4

IUPAC Name:

1-cyanoguanidine

Test material form:

solid: crystalline

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Bantin-Kingman Inc., Fremont, CA
- Age at study initiation: Males: 58 days at dosing - Females 33 to 41 days at dosing
- Weight at study initiation: Males 190 to 225 g at dosing - Females 140 to 174 g at dosing
- Fasting period before study: Males: not stated - Females: overnight
- Housing: individually in stainless steel wire mesh cages with automatically flushing dumptanks
- Diet: ad libitum: Certified Purina Rodent Chow No. 5002 (Ralston Purina Company, Checkerboard Square St. Louis, MD)
- Water: ad libitum: automatic lick dispensers
- Acclimation period: quarantine: 7 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): different rooms: (22.8 to 25.0) or (20.6 to 22.8) or (22.2 to 26.7 with a temporary drop to 18.9)
- Humidity (%): different rooms: (44 to 52 with a temporary spike to 64) or (44 to 64 with a temporary spike to 74 or (32 to 44)
- Air changes (per hr): not described
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: Males from 1984-03-14 to 1984-03-28 - Females from: 1984-03-21 to: 1984-04-11

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

methylcellulose

Remarks:

Tween® 80 + sterile water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 0,2 % methylcellulose, 0,4 % Tween® 80 in sterile water for injection
- Amount of vehicle (if gavage): Males 1.9 to 2.6 ml - Females 1.2 to 1.8 ml for dosed animals
2.0 ml for all vehicle control group animals
- Justification for choice of vehicle: data not available
- Lot/batch no. (if required):
methylcellulose (Sigma, St. Louis, MO, Lot Number 72F-047B)
Tween® 80 (Fisher Scientific, Fairtown, NJ, Lot Number 713137)
sterile water for injection (Cutter Medical, Berkeley, CA, Lot Number 426-27, 13 Mar 84, Lot Number CH7936, 20 Mar 1984)
- Purity: data not available

MAXIMUM DOSE VOLUME APPLIED: 2.6 ml

DOSAGE PREPARATION (if unusual):

Depending upon the dose level, various amounts of Guanidine Nitrate were weighed in a Mettler AK 160 Electronic Balance and were added to 50 ml of the vehicle for males and 25 ml of the vehicle for females to yield the desired dosing concentration. Complete analyses of the dosing
solutions/suspensions was performed for homogeneity and verification of concentrations.

Doses:

Males: 311 - 826 - 1000 - 1210 - 1470 mg/kg bw
Females: 610 - 718 - 847 - 1000 - 1180 - 1390 mg/kg bw

No. of animals per sex per dose:

Total animals dosed: 108
Dosing groups: 10 animals per sex
Exception: Females lowest dose group: 8 animals

Control animals:

yes

Remarks:

vehicle: 5 Males + 5 Females

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: daily
- Frequency of weighing: weekly
- Necropsy of survivors performed: yes
- Other examinations performed: (1) clinical signs (2) body weight (3) histopathology
Details for clinical signs:
1.1 behaviour ( includes ataxia, disorientation, hyperactivity, jumping, irritableness, inactivity, changes in preening, prostrate condition,
aggressiveness, sonnolence, tremors, twitching)
1.2 gastrointestinal (includes increased salivation, material in mouth, diarrhea, perianal staining)
1.3 respiratory (includes reddish nasal discharge and stains on head, increase in respiratory rate, decrease in respiratory depth)
1.4 ocular (Includes reddish material around eyes (chromodacryorrhea), conjunctivitis)
1.5 rough coat
1.6 hunched posture
1.7 normal throughout

Statistics:

Statistical analyses were performed on the study results. Selected lethal dose values were derived by probit analysis according to the maximum likelihood method. The program PROBIT, developed for the Data General Computer, Model MV8000, was used to determine the probit curve and lethal dose values.

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

989.6 mg/kg bw

95% CL:

> 793 - < 1 138

Remarks on result:

other: LD50 = 989.6 +/- 68.7

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

729.8 mg/kg bw

95% CL:

> 641 - < 799

Remarks on result:

other: LD50= 729.8 +/- 34.3

Mortality:

Forty-six (74 %) of the deaths occurred between 1 and 8 hours after dosing. An additional 13 (21 %} deaths occurred between 8 and 24 hours after dosing. Three animals were found dead on the morning of the second day (between 36 and 47 hours after dosing). Furthermore, 2 males and 1 female were inappropriately dosed resulting in latrogenic deaths. The remaining rats survived until completion of the study.

Clinical signs:

other: Guanidine nitrate produced clinical signs at each dose level. The most frequently observed signs were behavioral (63 of 99 animals dosed with test compound), gastrointestinal (GI) tract symptoms (37 of 99), and respiratory (26 of 99) signs. Most clinical

Gross pathology:

Latrogenic deaths due to oesophagal perforatin or tracheal tears and deposition of the test substance in the thorax occured in 2 males and 1 female. Thirteen females had multiple red foci on the thymus. None of the males had this lesion.

Other findings:

- Organ weights: not determined
- Histopathology: The presence of multiple red foci in the thymuses of the females was the only gross lesion which was attributable to the test compound. The presence of foci exhibited a dose-response relationship. The remainng lesions were considered incidential findings which are not compound related. No lesions were seen in the vehicle control animals.

Any other information on results incl. tables

Lethal dose values were calculated by probit analysis, and the equation for the probit regression line was:

Y = -19.6 + 8.2 log X for males and Y = -32.5 + 13.1 log X for females, where X is the dose and Y the corresponding probit value.

Misdosed animals were excluded from statistical analysis and eliminated from the study.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

The LD50 values for Guanidine Nitrate were determined to be 989.6 +/- 68.7 mg/kg in male and 729.8 +/-34.3 mg/kg in female animals.
Guanidine Nitrate is classified with Hazard Category 4 for acute oral toxicity (harmful if swallowed).

Executive summary:

In an acute oral toxicity study according to the Health effects test guidelines, August 1982, EPA 560/6-82-001, groups of Sprague Dawley rats (10/sex) were given a single oral dose of  guanidinte Nitrate (99.99 % a.i.) in methylcellulose, Tween® 80, sterile water at doses of 311, 826, 1000, 1210 and 1470 mg/kg bw (males) and 610, 718, 847, 1000, 1180 and 1390 mg/kg bw (females) and observed for 14 days.

 

Oral LD50   Males = 989.6 ± 68.7 mg/kg bw (95% C.I. > 793 - < 1138)

                      Females = 729.8 ± 34.3 mg/kg bw (95% C.I. > 641 - < 799)

     

 

65 animals died during the study, most of them during the first 8 hours after dosing. Weight gains of surviving animals were not significantly affected by dosing.

 

The primary category of clinical signs was behavioral (e.g., inactive, irritable, disoriented, hyperactive, ataxic) which was observed in 63 of 99 animals dosed with Guanidine Nitrate. Other categories of frequently observed clinical signs were gastrointestinal (e.g., material in mouth, perlanal staining, increased salivation, diarrhea) which was observed in 37 of 99 animals, and respiratory (e.g. reddish nasal discharge, increased rate and/or decreased depth of respiration) which was observed in 26 of 99 animals. These findings suggest that guanidine nitrate exhibits a primary effect on the central nervous / neuromuscular system.

The presence of multiple red foci in the thymuses of the females was dose related and the only gross lesion which was attributable to the test compound.

 

According to CLP, EU GHS (Regulation (EC) No 1272/2008), Guanidine Nitrate is classified with Hazard Category 4 for acute oral toxicity (harmful if swallowed). Findings may suggest that the guanidine ion exhibits a primary effect on the central nervous / neuromuscular system. However, effects were observed in the range of classification Hazard Category 4, therefore on the basis of available data no additional classification for STOT-SE is considered necessary. A sub-chronic repeated dose toxicity study is proposed, which will provide additional more detailed information for evaluation.