p-(dimethoxymethyl)anisole

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 26 Aug 1991 to 2 Oct 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study; GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

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

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

p-(dimethoxymethyl)anisole

EC Number:

218-577-4

EC Name:

p-(dimethoxymethyl)anisole

Cas Number:

2186-92-7

Molecular formula:

C10H14O3

IUPAC Name:

1-(dimethoxymethyl)-4-methoxybenzene

Details on test material:

- Name of test material (as cited in study report): Anisaldehyddimethylacetal
- Batch No.: Kol. 5160SA
- Substance No.: 90/645
- Date of production: 24 Sep 1990
- Physical state: clear slightly viscous homogenous liquid
- Storage: room temperature
- Analytical purity: 94%
- Impurities (identity and concentrations): anisic acid methylester (4 %), anisaldehyde (0 .25% )
- Purity test date: Nov. 22. 1990
- Stability under test conditions: stability of the test substance was confirmed by reanalysis.

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. KARL THOMAE GmbH, Biberach/Riss, FRG
- Age at study initiation: 42 days
- Weight at study initiation: mean 187 g (males), 154 g (females)
- Fasting period before study: about 16 - 20 h
- Housing: housed singly in type DK III stainless steel wire cages supplied by BECKER & Co., Castrop-Rauxel, FRG, (floor area about 800 cm2)
- Diet (e.g. ad libitum): ground Kliba maintenance diet rat/mouse/hamster, 343 meal byKlingentalmühle AG, Kaiseraugst, Switzerland; ad libitum
- Water (e.g. ad libitum): drinking water; ad libitum
- Acclimation period: at least 8 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12 / 12


IN-LIFE DATES: From: 03 Sept 1991 To: 2 Oct 1991

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
To prepare the solution Anisaldehyddimethylacetal was weighed depending on the dose group, then olive oil DAB 9 was added and the mixture was subsequently dissolved by shaking. The test substance preparations were made in intervals for which the stability of the test substance preparations was proven.


VEHICLE
- Concentration in vehicle: 1, 4, 20 g/100 ml
- Amount of vehicle (if gavage): 5 ml/kg bw

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analyses regarding the characterization of the test substance were carried out prior to the start of the study. The stability of the test substance was confirmed by reanalysis. Before the beginning of the study, the evidence of stability of the test substance in the vehicle over a period of 4 hours and 4 days was ordered. Samples of each concentration obtained at the start of the study were sent to the analytical laboratory for determination of the correctness of the concentration of the test substance preparations. Due to analytical problems the reserve samples of test group 1 and 2 were also sent to the analytical laboratory.
The content of test substance preparations was determined by gas chromatography

Duration of treatment / exposure:

4 weeks

Frequency of treatment:

21 administrations (daily, except weekends)

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 50, 200, 1000 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

5

Control animals:

yes, concurrent no treatment

Details on study design:

- Dose selection rationale: based on results of an acute oral toxicity study and a 2-week administration study, where doses of 200 and
1000 mg/kg body weight were administered to male and female Wistar rats.

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: The animals were checked for the apearance of clinical signs before and after each test substance administration. A check was made twice (Mondays to Fridays) and once a day (Saturdays, Sundays and public holidays) for general observations and moribund animals.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Once a week an additional exact clinical examination was carried out

BODY WEIGHT: Yes
- Time schedule for examinations: once a week

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

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: in the morning of day 24 after beginning of administration
- Anaesthetic used for blood collection: No
- Animals fasted: No
- How many animals: 5/sex/ dose group
- Parameters checked: see below

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: in the morning of day 24 after beginning of administration
- Animals fasted: No
- How many animals: 5/sex/dose group
- Parameters checked: see below

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
Organ weights: spleen, thymus, adrenal glands ancl testes

HISTOPATHOLOGY: Yes
Liver, Kidneys, Stomach, Spleen, Thymus, Bone marrow, Adrenal glands, Heart, Mesenteric lymphnodes, Popliteal lymphnode, Urinary bladder, AIl gross lesions

Statistics:

Means and standard deviations were calculated for the variables food consumption, body weight and body weight change for the animals in each test group.
For clinical data a non-parametric one-way analysis of variance (KRUSKAL-WALLIS h-test) followed by a post test (MANN-WHITNEY U-test) for the hypotheses of equal medians.
For terminal body weight and of absolute and relative organ weights, a non-parametric one-way analysis of variance ( KRUSKAL-WALLIS-h test) followed by a post test (WILCOXON-Test) for the hypothesis of equal medians.

Results and discussion

Results of examinations

Details on results:

CLINICAL SIGNS AND MORTALITY
1000 mg/kg bw: Salivation only within 10 min after gavageing of the test substance from
the 17th application onwards.
No animal died during the course of the study .

BODY WEIGHT AND WEIGHT GAIN
1000 mg/kg bw: increased values of body weight change in males (about 9 %) and females (about 20 %)
No statistically significant differences in body weights.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
1000 mg/kg bw: increased food consumption in males and females (about 20% higher than control
values)

HAEMATOLOGY
1000 mg/kg bw: increase in polymorphonuclear neutrophils in the females (which was interpreted as signs of inflammation).

CLINICAL CHEMISTRY
1000 mg/kg bw: increase in triglycerides in both sexes

ORGAN WEIGHTS
1000 mg/kg bw: increase of absolute and relative liver weight in females

HISTOPATHOLOGY:
1000 mg/kg bw:
-hyperplasia of squamous mucosa layer of the forestomach in male and female animals
- ulcerations in the squamous mucosa layer of the forestomach in one male animal
- intracytoplasmatic vacuolation of the superficial layer of the transitional epithelium of the urinary bladder in male and female animals.

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

200 mg/kg bw/day (nominal)

Sex:

male/female

2

Dose descriptor:

LOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

other: irritation of the gastrointestinal tract, liver, urinary bladder

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Salivation only within 10 min after gavageing of the test substance is most probably a local effect on the gastrointestinal tract, but not a systemic toxic effect. This is confirmed by the fact, that hyperplasia (males and females) and even ulceration (one male) was observed histopathologically in the mucosal layer of the forestomach. Also the increased food consumption (with the corresponding increase in body weight) of the animals might be a compensatory reaction on the irritation of the forestomach.