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Toxicological information

Acute Toxicity: oral

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Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1.5. - 5.6.1985
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Acceptable, well documented study report which meets basic scientific principles.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1985

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
other: Acute exposure, oral toxicity. In: Health effects test guidelines. Washington, DC: EPA, Aug 1982, EPA 560/6-82-001
Deviations:
yes
Remarks:
See Overall remarks
Qualifier:
according to
Guideline:
other: Acute oral toxicity study (ADL and LD50). LAIR Standard Operating Procedure OP-STX-36, Letterman Army Institute of Research, Presidio of San Francisco, CA. 15 Jun 1984
Deviations:
yes
Remarks:
See Overall remarks
GLP compliance:
yes
Test type:
other: modified up-and-down procedure
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Diethyleneglycol Dinitrate (DEGDN)
- Physical state: pale yellow liquid
- Analytical purity: 96.6%
- Impurities (identity and concentrations): not identified
- Lot/batch No.: RAD84MOO1S214
- Stability under test conditions: stable

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Bantin and Kingman, Inc, Fremont, CA
- Weight at study initiation: 168 - 279 g
- Fasting period before study: overnight
- Housing:individually in stainless steel wire mesh cages in racks equipped with automatic flushing dumptanks, no bedding was used
- Diet (e.g. ad libitum): Certified Purina Rodent Chow Diet 5002 (Ralston Purina Company, St Louis, MO)
- Water (e.g. ad libitum): from central line
- Acclimation period: 12-19 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23.3 - 25.6 °C
- Humidity (%): 41 - 55%
- Photoperiod (hrs dark / hrs light): 12 hours of light per day

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 10 ml/ kg b.w. (1.98-2.79 ml/males, 1.68-2.4 ml/females)

DOSAGE PREPARATION (if unusual): DEGDN was received as a solution containing 18% acetone. The acetone was removed with a rotary evaporator. DEGDN was then suspended in corn oil to form a viscous yellow oily suspension.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: The results of an approximate lethal dose (ALD) determination suggested that the median lethal dose (MLD) was between 500 and 1000 mg/kg. Based on these data, test doses were selected.
Doses:
Males: 794, 891, 1000, 1120, 1260 mg/kg
Females: 631, 794, 891, 1000, 1260 mg/kg
No. of animals per sex per dose:
10 males and 10 females per dose
Control animals:
yes
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations:
- mortality and signs of acute toxicity: on the day of dosing 1, 2, 4, 6 hours after dosing and then daily
- weighting: weekly
- Necropsy of survivors performed: yes
Statistics:
The LD10, LD50 and LD90 were derived by probit analysis using the maximum likelihood method. The program, PROBIT, Model MV8000 was used to plot the probit curve and lethal dose values.

Results and discussion

Effect levelsopen allclose all
Sex:
male
Dose descriptor:
LD50
Effect level:
990 mg/kg bw
95% CL:
924 - 1 060
Sex:
female
Dose descriptor:
LD50
Effect level:
753 mg/kg bw
95% CL:
654 - 826
Mortality:
Forty-eight animals died as a result of the dosing. Twenty-five deaths (52.1%) occured within 24 hours of dosing. Fifteen deaths (31.2%) occured between 24 and 48 hours after dosing. The remaining 8 deaths (16.7%) occured between 18 and 120 hours after dosing.
Clinical signs:
Behavioral disturbances (73 of 79 animals) - inactivity, twitching, tremors, hypertonia, irritability, jumping and ataxia.
They were first observed 1 to 3 hours after dosing and, with exception of inactivity and irritability, were no longer observed 72 hours after dosing. Inactivity was last observed 4 days after dosing and isolated incidences of irritability were observed up to Day 8. Behavioral signs were present in all dose group with only the 794 mg/kg male group showing a noticeably lower incidence. Tremors and twitching exhibited an apparent dose response in male animals while the other behavioral signs showed no particular sex or dose response.

General signs
Hunched posture (45 of 79) - also in all the control animals
Prostration and moribund condition (28 of 79) - only in animals receiving the test substance, and in all cases in which these signs were observed, the animals subsequently died.

Ocular signs - squinting (49 of79), lacrimation (24 of 79) and chromodacryorrhea
Apparent dose response in the males. Only lacrimation exhibited a dose response in the female animals.

Reflexive signs (46 of 79) - depressed grasping or righting reflexes and increased startle reflex
Without any apparent dose response or sex-dependent relationships.

Skin related signs (27 of 79)) - cyanosis or bluing of the skin, feet, ears, tail, and face
First observed 1 to 6 hours after dosing and absent by 48 hours.

Miscellaneous signs (33 of 79) - stains on various areas of the body and abnormally colored urine

Other clinical signs
Observed infrequently and, except for a general paucity of effects in the 794 mg/kg male group, randomly distributed among the dose groups.
Included diarrhea, respiratory signs (increased respiratory rate, wheezing and tachypnea).
Most clinical signs appeared by 2 hours and cleared by 72 hours after dosing.

Body weight:
Weight gains of survivors were not affected by administration of DEGDN.
Gross pathology:
The mortalities which occured after dosing appear to have been caused by the test compound.
A dose-response effect on deaths was apparent in both male and female rats.
Multifocal necrohemorrhagic gastritis - probably treatment related.
Liver vacuolization - maybe related to treatment or maybe not
Renal autolysis, renal autolysis and renal necrosis

Applicant's summary and conclusion

Conclusions:
Diethyleneglycol dinitrate produces signs of neurotoxicity in addition to standard symptoms of nitrate ester poisoning. Calculated MLD values
were 990.4 ± 30.0 mg/kg in male Sprague-Dawley rats and 753.1 ± 35.9 mg/kg in female Sprague-Dawley rats.
Executive summary:

The acute oral toxicity of the nitrate ester, diethyleneglycol dinitrate (DEGDN), was determined in male and female Sprague-Dawley rats by using the oral gavage single-dose method. The median lethal dose (MDL) was 990.4 +/- 30 mg/kg for male rats and 753.1 +/- 35.9 mg/kg for female rats. Clinical signs produced by DEGDN included twitching, tremors, hypertonia, squinting, lacrimation, depression of grasping and righting reflexes, jumping, increased startle reflex, ataxia, cyamosis, inactivity, and prostration. The extent of the neurotoxic component of this clinical signs profile suggests that DEGDN possesses additional pharmacological properties to those routinely associated with the nitrate esters. The duration of clinical signs was acute. Most animals were exhibiting signs by 2 hours after dosing and had either died or cleared by 72 hours after dosing.