Registration Dossier

Administrative data

Endpoint:
sub-chronic toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
26 October- 30 January 2001
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study was conducted under GLP conditions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001
Report Date:
2001

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report: T-7499; Perflurobutyl sulfonyl fluoride
- Physical state: Clear colorless liquid
- Analytical purity: 96-98 % Perfluorobutyl sulfonyl fluroide; 2-4% Perfluorosulfolane
- Lot/batch no.: None stated
- Expiration date of the lot/batch: None stated
- Stability under test conditions: stable
- Storage condition of test material: Ambient temperature or in a refrigerator, unless otherwise stated by the sponsor.

Test animals

Species:
rat
Strain:
other: Crl:CD BR Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River (UK) Limited, Manston Road Margate, Kent.
- Age at study initiation: approximately 6 weeks
- Weight at study initiation: 163-293g
- Housing: 5 animals of the same sex in suspended stainless steel cage fitted with mesh front, back and floor with stainless steel sheet sides. Exposure occured in the same room animals were housed.
- Diet (e.g. ad libitum): ad libitum (to a weighed amount of quality control food)
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 7 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C):19.5-21.0 degrees C
- Humidity (%):39-58%
- Photoperiod (hrs dark / hrs light): 12 hours light/12 hours dark
IN-LIFE DATES: From: 13 November To: 30 January 2001

Administration / exposure

Route of administration:
inhalation: vapour
Type of inhalation exposure:
whole body
Vehicle:
other: Unchanged (no vehicle) : clean air used as a diluent
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: vapor genarator
- System of generating particulates/aerosols: produced by metering the test liquid into stainless steel coil vapour generators and was diluted with clean air prior to the resultant vapour atmosphere passing into the exposure chamber.
- Temperature, humidity, pressure in air chamber: Temperature in chamber was 21-22 degrees C. Chamber pressure was -2 to -4 mm water. Relative humidity was 19-32%
- Air flow rate: 150 l/min (100 l/min diluent air and 50 l/min test substance)
- Treatment of exhaust air: vented to an exhaust stack

VEHICLE (if applicable)
- Justification for use and choice of vehicle: diluent air
Duration of treatment / exposure:
6 hour exposure
Frequency of treatment:
5 consecutive days of each week for 4 weeks
Doses / concentrations
Remarks:
Doses / Concentrations:
0 (control), 50 ppm, 150 ppm and 450 ppm (study mean exposure levels were 47, 162 and 459 ppm).
Basis:
nominal conc.
Control animals:
other: Yes, exposed to diluent air to the same methods the exposed groups
Details on study design:
- Dose selection rationale: after discussion with sponsor and the review of available data

Examinations

Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: cages were checked for mortality in the morning and at the end of the normal working day.
- Cage side observations included observations of dead or moribund animals.
DETAILED CLINICAL OBSERVATIONS: Yes

BODY WEIGHT: Yes
- Time schedule for examinations: weekly, commencing 1 week prior to the start of exposures and when any possibly significant observations were made during daily checks or at anytime during the study.
FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No, this is not a feeding study, but food consumption is calculated as group mean values as grams/animal.
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No
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 data
WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No data

HAEMATOLOGY: Yes
- Time schedule for collection of blood: week 4 of exposure
- Anaesthetic used for blood collection: No data
- How many animals: all animals
- Parameters checked in table [No. 1] were examined.
CLINICAL CHEMISTRY: Yes
- Parameters checked in table [No.2] were examined.
URINALYSIS: No
- Parameters checked in table [No.2] were examined.
NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: a full functional observation battery was performed during the pre-treatment period and during week 4. A shortened batery was performed during weeks 1, 2, and 3.
- Dose groups that were examined: All dose groups were tested.
- Battery of functions tested: Observations in the hand: ease of removing animal from cage, reactivitiy to handling, occurence of convulsions, tremors, twitches, salivation/lacrimation, palpebral closure, exophthalmus, piloerection, fur appeance, vocalisation on handling;
Observations in the arena: occurrence of convulsions, tremors, twitches, activity counts, level of arousal, rearing count, grooming, piloerection, assessment of gait/posture, record presence of fecal boluses, urine; Manipulations: approach response, touch response, auditory startle response, righting reflex, tail pinch response, pupil reflex, grip strength (fore and hindlimb), landing footsplay, body temperature and bodyweight.
Sacrifice and pathology:
GROSS PATHOLOGY: Yes (see table 3)
HISTOPATHOLOGY: Yes (see table 4)

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):
no effects observed
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
not examined
Behaviour (functional findings):
effects observed, treatment-related
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Details on results:
CLINICAL SIGNS AND MORTALITY: There were no unscheduled deaths. Clinical signs observed as a group response during exposure included vocalising and agitation when handled for Groups 2, 3, and 4. Walking on toes (abnormal gait) was evident following the exposures for Groups 3 and 4. Hyperactivity was observed following the exposures for Groups 3 and 4 during weeks 2 and 3. This sign was also evident following the exposures for Group 2 rats during Week 3. On three occasions, signs were present prior to exposure. Agitation when handled was present for a Group 3 female rat prior to exposure on Day 17. Vocalising and agitation when handled were present for two Group 3 female rats prior to exposure on Day 19. Walking on toes (abnormal gait) was present for Group 4 female rats prior to exposure on Day 26. At all ofther times, all of the above signs had resolved prior to exposure the following day. At other times, dry skin abrasions to tails, irritable behaviour and pale coloured teeth were observed. These signs are considered incidental and not related to treatment.
BODY WEIGHT AND WEIGHT GAIN: The overall mean bodyweight gains for all test rats (weeks 0 to 4) were lower than controls, attaining a degree of statistical significance for all test males.
FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): This study was not a feeding study, but a reduction in food consumption was evident for Group 4 male rats. The food consuption of other test rats was considered not to be affected by treatment.
FOOD EFFICIENCY
WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study)
OPHTHALMOSCOPIC EXAMINATION
HAEMATOLOGY: No treatment related findings.
CLINICAL CHEMISTRYL: No treatment related effects
URINALYSIS
NEUROBEHAVIOUR: Functional observational battery findings for animals treated with the test article showed no evidence of neurotoxicity. In the hand observations were unaffected by treatment. Arena observations showed some inter-group variation but the differences were not considered to be treatment-related. Compared with controls, females in all treated groups showed reduced activity and rearing scores in the arena during week 3 of treatment, although scores for males were unaffected. In the absence of similar response patterns during, preceding, or subsequent weeks of treatment, these differences were considered to be due to natural variation. During week 4 of treatment, landing footsplay measurements for females receiving 150 or 450 ppm were lower than those of controls. Mean values for these groups were therefore not considered to be associated with treatment. The time spent in locomotor activity for males recieving 150 ppm was lower than that shown by control animals during Week 4 of treatment whereas, in contrast, females receiving 50 or 150 ppm showed increased activity times. These differences failed to achieve statistical significance and, in view of the lack of dosage-relationship and the opposing directions of change, were considered to be due to natural variation.
ORGAN WEIGHTS: No treatment related findings
GROSS PATHOLOGY: No treatment related findings.
HISTOPATHOLOGY: NON-NEOPLASTIC: No treatment related findings

Effect levels

Dose descriptor:
other: a No Observed Effect Level (NOEL) was not able to be established during this study.
Sex:
male/female
Basis for effect level:
other: see 'Remark'
Remarks on result:
not measured/tested
Remarks:
Effect level not specified (migrated information)

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
A no observed effect level was not established during this study. However, clinical signs consistent with a transient effect on nervous system had generally resolved prior to exposure the following day and there was no evidence of sustained neurotoxicity in the functional observation battery.
Executive summary:

Three groups (each of 5 males and 5 females) of the Crl: CD BR Sprague-Dawley strain were exposed to the test article for 6 hours a day for 5 consecutive days a week for 4 weeks using a whole-body exposure system. A fourth group, acting a control, was exposed to air only. The study mean analyzed concentrations of the test articles were 47, 162 and 459 ppm for the Low, Intermediate and High dose groups respectively. Clinical signs observed during exposure included circling movement and lethargy. Clinical signs observed immediately post exposure included vocalizing and agitation when handled, walking on toes (abnormal gait) and hyperactivity. These signs were consistent with a neurotoxic effect and generally resolved prior to exposure the following day. The overall mean bodyweight gains for all test rats (Weeks 0 to 4) were lower than controls, attaining a degree of statistical significance for all test males. A reduction in food consumption was evident for Group 4 male rats. There was no effect of treatment on the functional observational battery of haemotological and blood chemistry parameters. Necropsy revealed no treatment-related macroscopic findings and no treatment-related differences in organ weights. Histopathological examination of the respiratory tract revealed no treatment-related findings. A no observed effect level was not established during this study. However, clinical signs consistent with a transient effect on nervous system had generally resolved prior to exposure the following day and there was no evidence of sustained neurotoxicity in the functional observation battery.