Morpholine, 4-C12-14-alkyl derivs.

Acute Toxicity: oral

Administrative data

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: The study was conducted according to the OECD Guideline and EU Method in compliance with GLP. However, the guideline at the time applied 200 mg/kg rather than the current 300 mg/mg that is aligned with GHS classification.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Deviations:

yes

Remarks:

(the test method was based on the EEC Guideline B1, but modified according to Schlede et al. (A national validation study of the acute-toxic-class-method - An alternative to the LD50 test. Arch Toxicol 66: 455-470, 1992 )

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

72906-09-3

Cas Number:

72906-09-3

IUPAC Name:

72906-09-3

Test material form:

other: Liquid

Details on test material:

- Physical state: Liquid, colourless, clear
- Analytical purity: 93.5% (GC analysis)
- Lot/batch No.: V. 917 - Qualitaet II
- Stability of the test substance over the study period: Proven by reanalysis
- Stability of the test substance in the vehicle during 4 h: Confirmed by analysis
- Storage condition of test material: Room temperature, in absence of moisture

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. K. Thomae GmbH, Biberach, Germany
- Age at study initiation: Young adult animals were used
- Mean weight at study initiation: 150 - 300 g
- Fasting period before study: At least 16 h before administration
- Housing: Single housing in stainless steel wire mesh cages
- Diet: Kliba-Labordiaet 343 (Klingentalmuehle AG, Kaiseraugst, Switzerland), ad libitum
- Water: Tap water, ad libitum
- Acclimation period: At least 1 week

ENVIRONMENTAL CONDITIONS
- Temperature: 20 – 24°C
- Humidity: 30 – 70 %
- Photoperiod: 12 h dark/12 h light

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

- Concentration in vehicle: 4 g/100 mL for the low dose level (200 mg/kg bw) and 40 g/100 mL for the high dose level (2000 mg/kg bw).
- Justification for choice of vehicle: Since the test substance is insoluble in water, olive was used as vehicle.
- Maximum dose volume applied: 5 mL/kg bw.

Doses:

200 and 2000 mg/kg bw

No. of animals per sex per dose:

200 mg/kg bw:: 3 males and 3 females
2000 mg/kg bw:: 3 females

Control animals:

no

Details on study design:

OBSERVATION PERIOD
Treatment was followed by an observation period of 14 d for the low dose group (200 mg/kg bw, males and females), and 2 d for the high dose group (2000 mg/kg bw, females).

CLINICAL SIGNS AND MORTALITY
Observation for clinical symptoms was done on several times on the day of administration and at least once each workday thereafter; check for any dead or moribund animal was made twice each workday and once on saturdays, sundays and on public holidays.

BODY WEIGHT
Individual body weights were recorded shortly before administration (Day 0), weekly thereafter and on the last day of observation.

NECROPSY
At the end of the observation period the animals were sacrificed by CO2-inhalation and were subjected to gross pathology. No histological examinations were performed. Examination of all animals that died before test ending was conducted as early as possible after death.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 200 - <= 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: All animals of the 2000 mg/kg bw group (females) died within 2 d post-treatment. All animals treated with 200 mg/kg bw (males and females) survived.

Mortality:

200 mg/kg bw, males: No mortality
2000 mg/kg bw, females: All 3 females died within 2 d following treatment.

Clinical signs:

other: 200 mg/kg bw, females: No abnormalities 2000 mg/kg bw, females: All 3 females showed a poor general state and suffered from dyspnoea, apathy, ataxia, piloerection and shaking. In 2 cases, tremor and chromodacryorrhea also were noticed. In one case, twitch

Gross pathology:

Necropsy of animals that died: One female showed no abnormalies. The second and the third female showed congestive hyperemia and a moderate postmortal state; in one case, dark red discolouration of the urinary bladder also was noticed.
Necropsy of animals sacrificed at the end of the observation period: Gross pathological examination revealed no abnormalities.

Any other information on results incl. tables

Table:

Dose	Sex	Body weight range (g) for each test group
		Day 0	Day 7	Day 13
200 mg/kg bw	Males (n=3)	182 – 183 g	251 – 254 g	282 – 289 g
	Females (n=3)	173 – 176 g	197 – 201 g	208 – 217 g
2000 mg/kg bw	Females (n=3)	172 – 180 g	Not applicable due to mortality

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Remarks:

Migrated information

Conclusions:

Under the study conditions, the LD50 of the test substance in rats was >200 and =<2000 mg/kg bw.

Executive summary:

The acute toxicity of C12-14 alkylmorpholine was determined according to the EU Method B.1 and OECD Guideline 423 in compliance with GLP.

The guideline at the time applied 200 mg/kg rather than the current 300 mg/mg that is aligned with GHS classification. This is not considered to have an impact on the validity of the study.

A group of rats received an oral gavage dose of the test substance olive oil, at a dose level of 2000 (one test group comprising 3 females) and 200 mg/kg bw (one test group comprising 3 males and one test group comprising 3 females).

All animals of the 2000 mg/kg bw group died within 2 d after administration; thus, mortality at 2000 mg/kg bw was 100%. All animals treated with 200 mg/kg bw survived. Clinical symptoms of toxicity only were noticed and reported at 2000 mg/kg bw, almost consisting of a poor general state, apathy, dyspnoea, ataxia, piloerection and shaking. The findings almost were seen immediately after treatment and lasted up to death. Regarding body weight and body weight gain, these parameters were inconspicuous for both, the males and the females treated with 200 mg/kg bw. Necropsy of the sacrificed animals revealed no abnormalities. Gross pathological examination of those animals that died during the experiment revealed congestive hyperemia and a moderate postmortal state in two animals, accompanied in one case by dark red discolouration of the urinary bladder; the third animal showed no abnormalities.

Thus, the LD50 of the test substance in rats was >200 and =<2000 mg/kg bw.

According to OECD 423 Annex 2d, when all three animal died at 2000 mg/kg, and 0 -2 of the six animals at 300 mg/kg, the LD50 cut-off is set at 500 mg/kg bw. As 6/6 animals treated in this study at 200 mg/kg showed no signs of toxicity, no mortality is likely the case at 300 mg/kg.

Consqurently the LD50 cut-off is set at 500 mg/kg bw.