Dimantine

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

From 29 SEP 1994 to 04 OCT 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to the OECD Guideline and it is GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

GLP compliance:

yes (incl. QA statement)

Remarks:

according to §19 German Chemical Act

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Amines, C12-14-alkyldimethyl

EC Number:

283-464-9

EC Name:

Amines, C12-14-alkyldimethyl

Cas Number:

84649-84-3

Molecular formula:

R-N(Me)2, whereas R= C12-14-alkyl (even numbered, unbranched, saturated)

IUPAC Name:

N,N-dimethyl-C12-14-(even numbered)-alkyl-1-amines

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland GmbH
- Age at study initiation: male: 27 days; female: 29 days
- Weight at study initiation: males: 64-74 g; females: 65-75g
- Housing: granulated textured wood
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum



ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: sesame oil

Details on oral exposure:

14-day pilot studies were conducted with the dosages of 30, 100, 300 and 900 mg test item/kg b.w./day, by gavage. 30 and 100 mg/kg b.w. were tolerated well. 900 mg/kg bw /day was lethal within the first or second application. At 300 mg/kg bw/day all fpur animals showed slight salivation from the second dosing onwards.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Dose-levels: 0, 50, 150 and 300 mg/kg b.w./day

Duration of treatment / exposure:

one adaptation week and 28 days of treatment.

Frequency of treatment:

daily

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
(control) 2 mL sesame oil, DAB 10/kg b.w./day
Basis:
actual ingested

Doses / concentrations 2

Remarks:

Doses / Concentrations:
50 mg test item/ kg b.w./day
Basis:
actual ingested

Doses / concentrations 3

Remarks:

Doses / Concentrations:
150 mg test item/ kg b.w./day
Basis:
actual ingested

Doses / concentrations 4

Remarks:

Doses / Concentrations:
300 mg test item/ kg b.w./day
Basis:
actual ingested

No. of animals per sex per dose:

44 animals (22 male and 22 female animals); 4 animals (2 male and 2 female animals) of the total were reserved for possible replacement during the adaptation period)
Group 1: control: 5males/5 females
Group 2: low dose: 5 males/5 females
Group 3: intermediate dose: 5 males / 5 females
Group 4: high dose: 5males / 5 females

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: based on results of pilot study.

Positive control:

none

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: daily

BODY WEIGHT: Yes
- Time schedule for examinations: daily

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean weekly diet consumption calculated as g food/kg body weight: Yes

WATER CONSUMPTION: monitored but not measured.

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: at the end of the 4th test week
- Dose groups that were examined: all

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the end of the 4th test week
- Anaesthetic used for blood collection: Yes
- Animals fasted: Yes
- How many animals: all

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at the end of the 4th test week
- Animals fasted: Yes
- How many animals: all

URINALYSIS: Yes
- Time schedule for collection of urine: at the end of the 4th test week
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (all dose groups)
HISTOPATHOLOGY: Yes (highest dose group)

Statistics:

All values which differ significantly from control results according to R. A. Fisher's exact test are marked with * in the table summarizing of final examinations. In the paragraph "Results" special reference is made to all significant deviations. In case of significant deviations the t-value is stated and underlined in the synopsis of the respective table.

Results and discussion

Results of examinations

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

at 300 mg/kg bw/day 3/5 female animals died. At 150 and 300 mg/kg bw/day all animals showed rubbing of the snouts in the bedding material. In the highest concentration two females showed 24 h lasting salivation

Mortality:

mortality observed, treatment-related

Description (incidence):

at 300 mg/kg bw/day 3/5 female animals died. At 150 and 300 mg/kg bw/day all animals showed rubbing of the snouts in the bedding material. In the highest concentration two females showed 24 h lasting salivation

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

decrease only in the group with the highest concentration.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

decrease only in the group with the highest concentration.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

no effects observed

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

increase in the number of leucocytes in the highest dose group females.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

female rats of the highest dose group showed a significantly increased activity of the alanine aminotransferase (ALAT/GPT). For details see below

Urinalysis findings:

no effects observed

Description (incidence and severity):

for details see below

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

for details see below:

Histopathological findings: neoplastic:

not examined

Details on results:

HISTOPATHOLOGY: NON-NEOPLASTIC
The following organs were examined: adrenals, heart, kidney, liver, macroscopically visible lesions, liver, all possible organs. No substance related effects were observed.

Changes in the stomach of the two deceased femals rats (hyperkeratosis, erosions/ulcers in the region of the pars proventricularis, neurophilic granulocytic infiltration) were probably connected with alkaline properties of the test substance.

CLINICAL CHEMISTRY:
No substance-related changes were observed for sodium, potassium, calcium, chloride, total bilirubin, total protein, creatinine, glucose, blood urea, inorganic phosphorus, albumin, as well as for aspartate aminotransferase (Asat/GOT).

URINALYSIS
no substance related changes (protein, nitrite) were observed in any dose group.

Effect levels

Dose descriptor:

NOEL

Effect level:

50 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No substance related changes of the behaviour and external appearance were observed at this concentration compared with control animals. No mortalities at this dose level.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Under the present test conditions the no-observed-effect-level (NOEL) was 50 mg test item/kg b.w/day, by gavage for 28 days. Slight toxicity (rubbing of the snouts in the bedding material) was found after dosing 150 mg /kg b.w./day, by gavage. HIstopathological alterations (changes in the stomach) were only observed in the highest dose group for the two female animals that had died. This effect was probably connected to the alkaline properties of the test substance. No other histopathological changes were observed.
Females of the highest dose group showed a significantly increased activity of the alanine aminotransferase (ALAT/GPT), no other effects regarding parameters of clinical chemistry were observed. Rats of the highest dose group showed a reduced uptake of food as well as a reduced body weight.
No other effects were observed.
The symptoms observed were only of marginal severity and only of a short duration (up to 5 minutes) without any indication for systemic toxicity.
300 mg / kg b.w./day, by gavage, was within the lethal range.

Executive summary:

The test substance was tested in Sprague-Dawley rats in a subacute repeated dose study for 28 days. 40 animals were required, 5 animals/sex/group for groups 1 -4. The route of administration was oral by gavage and the volume administration was 2 mL/kg b.w./day using sesame oil as vehicle.

Under the present test conditions the no-observed-effect-level (NOEL) was 50 mg test item/kg b.w/day, by gavage for 28 days. Slight toxicity (rubbing of the snouts in the bedding material) was found after dosing 150 mg /kg b.w./day, by gavage. The symptoms observed were only of marginal severity and only of a short duration (up to 5 minutes) without any indication for systemic toxicity. However the highest concentration tested (300 mg test item/ kg b.w./day, by gavage) was within the lethal range.