Registration Dossier

Administrative data

Endpoint:
short-term repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: OECD guideline and GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1988
Report Date:
1988

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
Deviations:
no
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): chloressigsäuremethylester
- Physical state: colourless liquid
- Analytical purity: 99%

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Hoechst AG, Pharma-Forschung-Toxikologie, Kastengrund
- Age at study initiation: 45 days
- Weight at study initiation: males: 147-161 g; females: 144-158 g
- Diet (e.g. ad libitum): Altromin R1324 - Pellets (Altromin GmbH, Lage/Lippe), ad libitum.
- Water (e.g. ad libitum): tap water, ad libitum.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2 ºC
- Humidity (%): 50 ± 20%
- Photoperiod (hrs dark / hrs light): 12 hours light/12 hours dark

Administration / exposure

Route of administration:
inhalation: vapour
Type of inhalation exposure:
whole body
Vehicle:
other: unchanged (no vehicle)
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
The substance was applied continuously with a evaporator at 130 ºC. The preparation-air mixture was led by an air current of 800 l/h by a tube administration in the inhalation chamber. To reach the wished concentration as quickly as possible, the preparation was brought in two phases in the chamber.

TEST ATMOSPHERE
- Brief description of analytical method used: single-beam photometer
- Samples taken from breathing zone: yes


Analytical verification of doses or concentrations:
yes
Duration of treatment / exposure:
28 days
Frequency of treatment:
5 days per week (20 treatments), 6 hours daily
Doses / concentrations
Remarks:
Doses / Concentrations:
0, 10, 33, 100 ppm (0, 0.04, 0.14, 0.45 mg/l)
Basis:
nominal conc.
No. of animals per sex per dose:
10 animals per sex per dose
Control animals:
yes
Details on study design:
- Post-exposure recovery period in satellite groups: five animals per sex per dose were necropsied on day 1 after the 28-day exposure and five animals per sex per dose were necropsied on day 14 after the 28-day exposure.

Examinations

Observations and examinations performed and frequency:
CLINICAL OBSERVATIONS: Yes
- Time schedule: The behaviour and the general state of health of the animals were judged in each case once before the exposition beginning and after the exposition end as well as continuously during the exposition. Once at weekends as well as during the recovery periode the animals were examined daily.

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

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: Yes

WATER CONSUMPTION: Yes
- Time schedule for examinations: weekly

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: weekly

HAEMATOLOGY: Yes
- Time schedule for collection of blood: two groups of animals: day 1 after the 28-day exposure and day 14 after the 28-day exposure
- How many animals: Group 1: 5 animals per sex per dose; Group 2: 5 animals per sex per dose
- Parameters: erythrocyte count, haemoglobin, haematocrit, total and differential leucocyte count, platelet count, reticulocyte count (only for control and highest concentration groups), coagulation, thromboplastin time and partial thromboplastine time.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: two groups of animals: day 1 after the 28-day exposure and day 14 after the 28-day exposure
- How many animals: Group 1: 5 animals per sex per dose; Group 2: 5 animals per sex per dose
- Parameters: sodium, potassium, phosphorus, bilirubin, total bilirubin, creatinine, glucose, urea nitrogen, calcium, chloride, glutamic-pyruvic transaminase, glutamic-oxaloacetic transaminase, alkaline phosphatase, gamma glutamyl transpeptidase, cholesterol, triglycerides, total lipids, albumin, globulin and methaemoglobin.

URINALYSIS: Yes
- Time schedule for collection of blood: two groups of animals: day 1 after the 28-day exposure and day 14 after the 28-day exposure
- How many animals: Group 1: 5 animals per sex per dose; Group 2: 5 animals per sex per dose
- Parameters: appearance, colour, glucose, haemoglobin, bilirubin, pH and sediment.


NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: weekly
Sacrifice and pathology:
GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes
Other examinations:
Organ weights: absolute and relative weights of the following organs: heart, lungs, liver, kidneys, spleen, testicles, ovaries, adrenal glands, thyroid, brain.
Statistics:
The evaluation was executed using a program package for the evaluation of toxicological studies (Standard Operating Procedure von Dr. Passing, Abt. fur praktische Mathematik, durch Abt. Pharma Forschung Dokumentation).

Results and discussion

Results of examinations

Clinical signs:
effects observed, treatment-related
Mortality:
mortality observed, treatment-related
Body weight and weight changes:
effects observed, treatment-related
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Food efficiency:
effects observed, treatment-related
Water consumption and compound intake (if drinking water study):
no effects observed
Ophthalmological findings:
no effects observed
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
no effects observed
Behaviour (functional findings):
no effects observed
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
no effects observed

Effect levels

open allclose all
Dose descriptor:
NOEL
Effect level:
33 ppm
Sex:
female
Basis for effect level:
other: see 'Remark'
Dose descriptor:
NOEL
Effect level:
10 ppm
Sex:
male
Basis for effect level:
other: At 33 ppm: clinical signs such as narrowed eye lids, increased tendency to clean themselves, sneezing, retardation of the body weight development, reduced food consumption.

Target system / organ toxicity

Critical effects observed:
not specified

Any other information on results incl. tables

All test animals of the 10 and 33 ppm groups were free of clinical symptoms during the recovery period. In the animals of the 100 ppm group, the symtoms were still observable during the recovery period, up to day 35.

Applicant's summary and conclusion

Conclusions:
Based on the effects observed in a 28-day subacute inhalation study, the NOEL was 33 ppm for females and 10 ppm for males.
Executive summary:

A subacute inhalation study was carried out with the substance Methyl chloroacetate in Wistar rats. Ten animals per sex per group received 5 treatments per week during 28 days. The duration of each treatment was 6 hours and the following concentrations were used: 0, 10, 33 and 100 ppm. Five animals per sex per dose were necropsied on day 1 after the 28-day exposure. A satellite groups of five animals per sex per dose was maintained during a post-exposure period of 14 days. The following examinations were conducted: clinical signs, mortality, body weight, food consumption and food efficiency, water consumption, ophthalmoscopic examination, haematology, clinical chemistry, urinalysis, neurobehavioural examination, gross pathology, histopathology and organ weights. Based on the effects observed, such as clinical signs, retardation of the body weight development or changes in lung weight with no evidence of organ dysfunction, the NOEL was 33 ppm for females and 10 ppm for males.