Registration Dossier

Toxicological information

Repeated dose toxicity: inhalation

Currently viewing:

Administrative data

Endpoint:
short-term repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
03/08/2015 - 08/01/2016
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
Deviations:
yes
Remarks:
See Principles of Method
Principles of method if other than guideline:
PROTOCOL DEVIATIONS

This study was conducted in accordance with the protocol and protocol amendments, except for the following.

• Protocol Section 7.2 states that controls will be set to maintain a temperature of 71 ± 5°F (approximately 22 ± 3°C) and a relative humidity of 50 ± 20% within the animal holding room and that temperature and relative humidity will be monitored continuously. From 13-Aug-2015 through 19-Aug-2015, WIL Research experienced a computer network issue that impacted the Metasys PMI System’s ability to automatically control and record environmental conditions for various areas of the facility. Impact Assessment: This deviation did not have a negative impact on the integrity or results of the study as sufficient environmental data were recorded automatically or manually to demonstrate that the animals were maintained under acceptable conditions.

• Protocol Section 8.1 states that animal will be acclimated to restraint in nose-only exposure restraint tubes by increasing the restraint time over the acclimation period (first day, 1 hour; second day, 2 hours; third day, 3 hours; fourth day, 4 hours; and fifth day, 6 hours). On the second day of acclimation, some males and females remained in the restraint tubes for 2 hours 19minutesto 2 hours 20 minutes. Impact Assessment: This deviation did not negatively impact the quality or integrity of the data or the outcome of the study because these times were only 1-2minutes outside the acceptable time range.

• Protocol Section 9.3.1 states that animals will receive a daily observation 0-1 hour (+0.25 hr) following the exposure. On study day 7, male no. 1959 in the 242,912 mg/m3 (40,000 ppm) group did not receive an observation following exposure. Impact Assessment: This deviation did not negatively impact the quality or integrity of the data or the outcome of the study because a single missed observation for a single animal had no effect or impact on the study results.

• Protocol Section 9.5states that food weights will be recorded weekly throughout the study period. On study day 13, all food jars were removed without being weighed. As a result, there is no food consumption data for the study day 7-14interval. Impact Assessment: This deviation did not negatively impact the quality or integrity of the data or the outcome of the study because there was no effect on body weight during the study day 7-14 interval, thus it is unlikely that there was an effect on food consumption during the same interval.

• Protocol Section 9.9.1 lists the tissues to be collected at necropsy, and Protocol Section 9.9.3 details the animals from which these tissues will be examined microscopically. The following tissues were missing, precluding microscopic examination: bronchial lymph nodes from 1 female in the control group and parathyroids (1 or both) from 4 males and 3 females in the control group and 2 males and 3 females in the 242,912 mg/m3 (40,000 ppm) group. Impact Assessment: This deviation did not negatively impact the quality or integrity of the data or the outcome of the study because the number of tissues examined from each treatment group was sufficient to allow detection of test substance-related alterations.

• Protocol Section 9.9.1 states that the nasal cavity and brain from all animals will be retained in 10% neutral-buffered formalin, and Protocol Section 9.9.3 details the animals from which these tissues will be examined microscopically. The nasal cavity and both olfactory bulbs from female no. 2007 in the control group were lost at necropsy and were not available for microscopic examination. Impact Assessment: This deviation did not negatively impact the quality or integrity of the data or the outcome of the study because the nasal cavity and olfactory bulbs from control group females were available.

• Protocol Section 9.9.1 states that the coagulating glands will be examined for all males at the time of necropsy. For the primary necropsy on 23-Sep-2015, the coagulating glands were selected for females only in the program that sets up the necropsy tissue list. Therefore, the gross examination of coagulating glands was not documented at the primary necropsy. Impact Assessment: This deviation did not negatively impact the quality or integrity of the data or the outcome of the study because the coagulating glands in the control and high-exposure groups were examined microscopically.

GLP DEVIATIONS

Subpart E 160.81(a) states that a testing facility shall have standard operating procedures in writing, setting forth study methods that management is satisfied are adequate to ensure the quality and integrity of the data generated in the course of the study. All deviations in a study from standard operating procedures shall be authorized by the study director and shall be documented in the raw data. Significant changes in established standard operating procedures shall be properly authorized in writing by management. During this study, the SOP for the use of the temperature and humidity calibration equipment was in the revision process. The proper form for use of an SOP in revisions was not used, and management and the Study Director did not authorize the new procedure prior to the revised SOP being issued.

Impact Assessment: This deviation had no impact on the study as the temperature and humidity calibration procedure used during the study was the same procedure that is described in the revised SOP that was approved by management.

Subpart G 160.130(e) states that all data entries shall be dated on the day of entry and signed or initialled by the person entering the data. The personnel embedding tissues in paraffin for female no. 1996 in the 60,728 mg/m3 (10,000 ppm) group and female nos.1995, 2000, 2018, and 2022 in the 151,820 mg/m3 (25,000 ppm) groups was not documented on 06-Oct-2015, the date the function was performed. The personnel boxing the microscopic slides was also not recorded on 03-Nov-2015 and therefore cannot be determined.

Impact Assessment: These inadvertent documentation errors were minor GLP deviations and had no impact on the study or the study results.
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
gas
Specific details on test material used for the study:
The purity of the test substance was 98.371%(lot no. 150407-1)and 98.493% (lot no. 150407-2). The test substance was stored at room temperature (approximately 18°C to 24°C) and was considered stable under this condition. A reserve sample from each shipment of the test substance was collected and stored in the WIL Research Archives.

Test animals

Species:
rat
Strain:
Crj: CD(SD)
Sex:
male/female
Details on test animals and environmental conditions:
All animals were housed throughout acclimation and during the study i n an environmentally controlled room. The room temperature and relative humidity controls were set to maintain environmental conditions of 71±5°F (22±3°C) and 50±20%, respectively. Room temperature and relative humidity data were monitored continuously and were scheduled for automatic collection on an hourly basis. These data are summarized in Appendix F. Actual mean daily temperature ranged from 70.0°F to 71.4°F (21.1°C to 21.9°C) and mean daily relative humidity ranged from 42.3% to 55.9% during the study. Fluorescent lighting provided illumination for a 12-hour light (0600hours to 1800hours)/12-hour dark photoperiod. The light status (on or off) was recorded once every 1 5minutes. The 12-hour light/12-hour dark photoperiod was interrupted as necessary to allow for the performance of protocol-specified activities. Air handling units were set to provide a minimum of 10fresh air changes per hour.

Administration / exposure

Route of administration:
inhalation: gas
Type of inhalation exposure:
nose only
Vehicle:
air
Details on inhalation exposure:
The selected route of administration for this study was inhalation exposure because this is a potential route of unintended human exposure. Nose-only exposure methods were used to reduce overall test substance requirements. The 6-hour period of restraint was necessary to achieve the exposure duration set forth in the OECD 412 testing guideline.
Analytical verification of doses or concentrations:
yes
Duration of treatment / exposure:
6 Hours
Frequency of treatment:
5 days per week, over 4 weeks (minimum of 20 exposures)
Doses / concentrationsopen allclose all
Dose / conc.:
0 ppm (nominal)
Dose / conc.:
10 000 ppm (nominal)
Dose / conc.:
25 000 ppm (nominal)
Dose / conc.:
40 000 ppm (nominal)
Dose / conc.:
60 728 mg/m³ air (nominal)
Dose / conc.:
151 820 mg/m³ air (nominal)
Dose / conc.:
242 912 mg/m³ air (nominal)
No. of animals per sex per dose:
5
Control animals:
yes, concurrent no treatment

Examinations

Observations and examinations performed and frequency:
Standard toxicity endpoints included clinical observations, body weights, food consumption, functional observational battery (FOB) and motor activity (MA) assessments, macroscopic examinations, organ weight determinations at necropsy, and microscopic examination of tissues. This pathology report addresses the anatomical pathology and clinical pathology endpoints of the study.

Results and discussion

Results of examinations

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Food efficiency:
no effects observed
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
Immunological findings:
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Neuropathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
no effects observed
Other effects:
no effects observed

Effect levels

open allclose all
Key result
Dose descriptor:
NOEC
Effect level:
> 244 946 mg/m³ air (analytical)
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable due to absence of adverse toxic effects
Key result
Dose descriptor:
NOEC
Effect level:
> 40 335 ppm (analytical)
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable due to absence of adverse toxic effects

Target system / organ toxicity

Key result
Critical effects observed:
no

Any other information on results incl. tables

All animals survived to the scheduled necropsies.  There were no test substance-related clinical findings noted in males and females at any exposure level.

No test substance-related effects on body weights, body weight gains, or food consumption were observed in the 60,728 mg/m3 (10,000 ppm), 151,820 mg/m3 (25,000 ppm), or 242,912 mg/m3 (40,000 ppm) group males and females.

Functional observational battery parameters (home cage, handling, open field, sensory, neuromuscular, and physiological observations) and motor activity in males and females were not affected by test substance exposure at any exposure concentration.  

Exposure to the test substance resulted in no test substance-related alterations in hematology, coagulation, serum chemistry, and urinalysis parameters, organ weights, or macroscopic or microscopic findings.

Applicant's summary and conclusion

Conclusions:
Based on the results of this study, exposure to HCFO-1224yd(Z) to Crl:CD(SD) rats at concentrations of 60,728 mg/m3 (10,000 ppm), 151,820 mg/m3 (25,000 ppm), and 242,912 mg/m3 (40,000 ppm) via nose-only inhalation for 6 hours per day on a 5-day per week basis for 28 days resulted in no lethality or test substance-related effects in males and females at any exposure level. Therefore, the no-observed-effect concentration (NOEC) was considered to be 242,912 mg/m3 (40,000ppm). The actual mean analyzed concentration at this exposure level was 244,946 mg/m3 (40,335 ppm).
Executive summary:

Based on the results of this study, exposure to HCFO-1224yd(Z) to Crl:CD(SD) rats at concentrations of 60,728 mg/m3 (10,000 ppm), 151,820 mg/m3 (25,000 ppm), and 242,912 mg/m3 (40,000 ppm) via nose-only inhalation for 6 hours per day on a 5-day per week basis for 28 days resulted in no lethality or test substance-related effects in males and females at any exposure level.  Therefore, the no-observed-effect concentration (NOEC) was considered to be 242,912 mg/m3 (40,000ppm).  The actual mean analyzed concentration at this exposure level was 244,946 mg/m3 (40,335 ppm).