N-ethyl-N-methylcarbamoyl chloride

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

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:

-

EC Number:

479-390-3

EC Name:

-

Cas Number:

42252-34-6

Molecular formula:

C4H8ClNO

IUPAC Name:

N-ethyl-N-methylcarbamoyl chloride

Test material form:

liquid

Remarks:

colourless.

Specific details on test material used for the study:

- Name of test material (as cited in study report): EMCA
- Physical state: Colourless liquid
- Analytical purity: 99.3 %

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deuthschland, Sulzfeld, Germany.
- Age at study initiation: Eight to twelve weeks old.
- Weight at study initiation: Body weight did not exceed ± 20 %.
- Fasting period before study: Yes, overnight for a maximum of 20 hours.
- Housing: Three animals per cage in labelled Macrolon cages containing sterilised sawdust as beeding material and paper as cage enrichment.
- Diet : ad libitum to pelleted rodent dient.
- Water (e.g. ad libitum): Tap water ad libitum-
- Acclimation period: 5 days.
- Other: Females nilliparous and non-pregnant females were selected.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.6 - 21.7 ºC
- Humidity (%): 36-80 %
- Air changes (per hr): 15 air changes per hour.
- Photoperiod (hrs dark / hrs light): 12 hours artificial fluorescent light/12 hours dark

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 0.27 mL/kg bw (300 mg/kg bw dose) and 1.80 mL/kg-bw (2000 mg/kg bw dose).

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: When there is no information on a substance to be tested, for animal welfare reasons it is recommended to use the starting dose of 300 mg/kg
body weight. Therefore, this was chosen as the starting dose.

The toxicity of the substance was assessed by stepwise treatment of groups of 3 females. The first group was treated at a dose lvel of 300 mg/kg-bw. The absence of presence of mortality of animals dosed at one step determined the next step. The onset, duration and severity of the signs of toxicity were taken into account for determination of the time interval between the dose groups.

Doses:

300 and 2000 mg/kg-bw

No. of animals per sex per dose:

6 females for the 300 mg/kg-bw dose and 3 females for the 2000 mg/kg-bw dose.

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing: Mortality and viability were determined twice daily, the time of death was recorded as precisely as possible, weight was determined on day 1 (pre-administration), 8 and 15, clinical signs were periodically registered on day 1 and once daily thereafter until day 15.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

1 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: cut-off value.

Mortality:

Two females treated at 2000 mg/kg-bw were found on day 1. No further mortality occured at 2000 and 300 mg/kg-bw

Clinical signs:

300 mg/kg-bw: Hunched posture, uncoordinated movements, piloerection
2000 mg/kg-bw (surviving animal): Hunched posture, piloerection
2000 mg/kg-bw (animals found dead): Lethargy, flat/cramped posture, slow breathing, piloerection, watery discharge from both eyes, hyperthermia.
The surviving animals had recovered from clinical signs by day 2.

Body weight:

The mean body weight gain shown by surviving animals was considered to be similar to that expected of normal untreated animals of the same age and strain.

Gross pathology:

Many dark red foci in the glandular mucosa of the stomach were found in one animal that died during experiment. Macroscopic examination of the other animal that died during the experiment and surviving animals did not reveal any abnormalities.

Any other information on results incl. tables

Table 1. Summary of results.

Step	No. of animals	Dose (mg/kg bw)	Mortality	Interpretation	LD50cut-off (mg/kg bw)
1	3	300	0	Category 4. > 300 – 2000 mg/kg bw	1000
2	3	300	0
3	3	2000	2

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Remarks:

EU criteria.

Conclusions:

The oral-LD50 value for the test subtance in Wistar rats was between 300 and 2000 mg/kg-bw. According to the OECD 423 test guideline, the LD50 cut-off value was considered to be 1000 mg/kg bw.

Executive summary:

An acute oral toxicity study was performed according to OECD 423 with the test item under GLP conditions. Initially a group of 3 female rats was exposed to the test item by a single oral dose by gavage at 300 mg/ kg body weight. In a stepwise procedure, additional groups of female rats were dosed at 300 and 2000 mg/kg-bw. All animals were subject to daily observations and weekly determinations of bodyweight. Macroscopic examination was performed on the day of the death or after terminal sacrifice at day 15 . Two deaths occured on day 1 in the group of the highest dose level, no further mortality occurred. Clinical signs observed in death animals included lethargy, flat/cramped posture, slow breathing, piloerection, watery discharge from both eyes and hyperthermia, while clinical signs of the animals that survived the experiment included hunched posture, uncoordinated movements and piloerection.

The surviving animals had recovered from the symptoms on day 2. Based on the results the oral LD50 for the test substance in rat is between 300 and 2000 mg/kg body weight. According to the OECD 423 test guideline, the LD50 cut-off value was considered to be 1000 mg/kg bw.