Hexafluoropropene, oxidized, oligomers, reduced, fluorinated

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

other: Expert judgment

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: OECD Test Guideline 413

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Route of administration:

inhalation: vapour

Type of inhalation exposure (if applicable):

whole body

Reproductive organs were examined macroscopically and microscopically following the 90-day exposure period: testes, epididymides, seminal vesicles, prostate ovaries, uterus. No effects were noticed on any of these organs.

Key result

Dose descriptor:

NOAEC

Effect level:

10 075 ppm (analytical)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

histopathology: non-neoplastic

other: No effects were observed on reproductive organs.

Critical effects observed:

no

Remarks on result:

not measured/tested

Key result

Reproductive effects observed:

no

Conclusions:

Reproductive organs were examined macroscopically and microscopically following the 90-day exposure period: testes, epididymides, seminal vesicles, prostate ovaries, uterus. No effects were noticed on any of these organs raising no alert for the reproductive function. The only biologically significant change seen in this study on H GALDEN was centrilobular hypertrophy of the liver in the majority of High dose animals (correlating with an increased bodyweight-adjusted liver weight) and a proportion of Intermediate animals. There was no concurrent alteration of biochemical parameters (e.g., hepatic enzymes). As this is considered to be an adaptive response to exposure of the test material rather than an indication of toxicity it is concluded that No Adverse Effect Concentration (NOAEC) was 10075 ppm (115209 mg/m3) and that the No Effect Concentration (NOEC) was 1014 ppm (11595 mg/m3).

Executive summary:

H GALDEN was administered to rats by whole body inhalation exposure for 13 weeks. Three groups (each of 10 males and 10 females) were exposed to target concentrations of 1000, 3300 and 10000 ppm, 6 hours a day, 5 days a week for 13 consecutive weeks. A fourth group acting as a control was exposed to air alone.

During the study clinical signs, physical examination, arena observations were recorded. Bodyweight and food consumption were recorded weekly. Water consumption was recorded daily. Sensory reactivity, grip strength and motor activity were recorded for all animals in Week 12. Opthalmoscopy was performed on all animals pre-dose and in Week 13. In Week 13, haematology, biochemistry and urinalysis was undertaken. Following the 13-week period, all animals were sacrificed on the day following the last exposure

and subjected to a full macroscopic examination and a range of organ weights recorded. Histopathological examinations were carried out on selected tissues from all animals (dependent upon dose group).

Mean analysed vapour concentrations of HFPE were 1014, 3297 and 10075 ppm. These levels were in good agreement with the target exposure levels of 1000, 3300 and 10000 ppm.

Reproductive organs were examined macroscopically and microscopically following the 90-day exposure period: testes, epididymides, seminal vesicles, prostate ovaries, uterus. No effects were noticed on any of these organs raising no alert for the reproductive function. The only biologically significant change seen in this study was centrilobular hypertrophy of the liver in the majority of high dose animals (correlating with an increased in bodyweight-adjusted liver weight) and a proportion of intermediate dose animals. As this is considered to be an adaptive response to exposure of the test material rather than an indication of toxicity it is concluded that the No Adverse Effect Concentration (NOAEC) was 10075 ppm (115209 mg/m3) and that the No Effect Concentration (NOEC) was 1014 ppm (11595 mg/m3).

Cross-reference 2

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH: see RAAF document attached

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Dose descriptor:

NOAEC

Effect level:

10 075 ppm (analytical)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

histopathology: non-neoplastic

Critical effects observed:

no

Remarks on result:

not measured/tested

Reproductive effects observed:

no

Conclusions:

Reproductive organs were examined macroscopically and microscopically following the 90-day exposure period with the structural analogue H GALDEN: testes, epididymides, seminal vesicles, prostate ovaries, uterus. No effects were noticed on any of these organs raising no alert for the reproductive function.
Based on an analogue approach, the target substance GALDEN LMW is anticipated to have a similar toxicological profile, as a worst case, i.e. with a low toxicity and no anticipated effect on the reproductive function.

Cross-reference 3

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17 October 2001 to 01 October 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

OECD Guideline-conform study conducted under GLP .

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Crl:CD rats

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: livestock farming
- Age at study initiation: 10-11 weeks
- Weight at study initiation: about 224-340 g
- Fasting period before study: no. Animals had no access to food during the 6-hour inhalation exposures.
- Housing: 5 animals /cage
- Diet (e.g. ad libitum): pellet diet ad libitum
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 3-4 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-21 °C (measured)
- Humidity (%): 46-66 % (measured)
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12 hour cicle (6.00 a.m.- 6.00 p.m.)

Route of administration:

inhalation: vapour

Type of inhalation exposure (if applicable):

whole body

Vehicle:

air

Details on exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Whole body exposure chambers
- Method of holding animals in test chamber: Animals were placed into individual compartment of the exposure chamber. A separate exposure chamber was used for each group. The Control animals were exposed using an identical exposure chamber to that used for the test groups.
- Source and rate of air: about 60 - 100 l/minute
- Method of conditioning air: Air supplied to the vapour generators and secondary dilution vessels was filtered to remove any residual particulate and was dried.
- System of generating vapour: The chamber atmospheres were produced by metering the liquid test substance into glass vapour generators through which dried and heated air was passed at a group dependent flow rate ranging from 60 to 100 l/minute. For all exposed groups, the vapour/air mixture produced in the vapour generators was passed into the base of a secondary dilution vessel. A further supply of clean and dry air was supplied to Groups 2 and 3. The air supply to Group 4 was provided solely by the vapour generation system.
- Temperature, humidity, pressure in air chamber: The mean temperatures in chambers ranged between 22.5 °C +-0.85 (Group 1 Chamber) and 24.0 °C +- 0.91 (Group 4 Chamber). The mean relative humidity (RH) in chambers ranged between 38% +- 3.5 (Group 4 Chamber) and 47% +- 5.8 (Group 1 Chamber).
- Air flow rate: 100 litre/minute
- Air change rate: not reported
- Method of particle size determination: not relevant
- Treatment of exhaust air: not reported

TEST ATMOSPHERE
- Brief description of analytical method used: Gas Chromatograph was used to measure the concentration of H GALDEN in the test atmospheres within the four inhalation chambers.
- Samples taken from breathing zone: yes. Chamber atmosphere was sampled in sequence from each of the four exposure chambers and from one point within each chamber. Air from each chamber was continually drawn through a transfer line, which was therefore equilibrated with the mean concentration from each chamber. Every seven minutes, air from the transfer lines was swiched to the injection loop pf the gas chromatograph for automated analysis and data logging. When not being sampled, these transfer lines were pumped to waste.

VEHICLE (if applicable)
- Justification for use and choice of vehicle: air
- Composition of vehicle: air
- Type and concentration of dispersant aid (if powder): not relevant
- Concentration of test material in vehicle: 1004, 3367, 10006 ppm
- Lot/batch no. of vehicle (if required): not relevant
- Purity of vehicle: not relevant

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The samples of chamber atmosphere were injected into a gas chromatograph, which was calibrated using vapour standards prepared in gas sampling bags.

Vapour samples were collected using an automated system fitted with electrically controlled valves, which were manipulated using Chamber Environment Monitoring System (CEMS-2) software.
The test atmosphere was drawn directly from the inhalation chamber through the sample line to the gas-sampling valve located on the GC. Initially, the gas-sampliong valve of the GC was set to the "load" position and the valve was automatically switched to the "inject position" after 60 seconds. Simultaneously, the GC activates the start of the run sequence.

Chromatographic conditions:
Analytical column: DB-1, 5 micrometer film thickness, 30 m x 0.53 mm i.d.
Carrier gas: Helium (2.1 ml/minute)
Split ratio 1:25
Oxidant: Air ( 330 ml/minute)
Fuel: Hydrogen (33 ml/minute)
Injection volume: 500 microliter via an automated gas valve
Injection temperature: 200 °C
Detector temperature: 200 °C
Range: 1000
Gas sample valve: Off at 2.5 minute
Retention time H GALDEN: approximately 0.6-2.3 minutes (analysis for major peak at 0.9 minutes)

Details on mating procedure:

Time-mated females were supplied from the livestock farming. Females arrived to the Laboratory on Days 2 or 3 of gestation.
The females were mated by identified males.

Duration of treatment / exposure:

6 hours

Frequency of treatment:

6 hours/day for 14 consecutive days

Duration of test:

3-4 days of acclimatisation + 14 days of exposure period (Gestation days 6 to 19)

Dose / conc.:

0 ppm (analytical)

Dose / conc.:

1 004 ppm (analytical)

Remarks:

Target: 1000 ppm

Dose / conc.:

3 367 ppm (analytical)

Remarks:

Target: 3300 ppm

Dose / conc.:

10 006 ppm (analytical)

Remarks:

Target: 10000 ppm

No. of animals per sex per dose:

25 mated females

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose levels were selected in consultation with the sponsor, based on the results of a 14 day repeated dose preliminary toxicity study.
- Rationale for animal assignment: Animals were allocated to groups randomly on arrival. A review of the mating details provided by the supplier confirmed that no females allocated to the same group had been mated with the same male.

Maternal examinations:

DETAILED CLINICAL OBSERVATIONS: Yes
Dated and signed records of appearence, change and disappearence of clinical signs were maintened for individual animals.
Individual animal were observed at least once daily for any signs of behavioural changes, reaction to treatment or ill health. In addition, detailed observations were made daily, on the days of exposure, as follows:
- Pre exposure observations
- During exposure
- As each animal was returned to its home cage
- As late as possible in the working day.
During the daily exposure, obvious signs were recorded as a group response, where all visible animals appeared to be responding similarly to the test substance. Due to the type of exposure system used the ability to observe individual animals during the exposures was severely restricted.
Throughout the study, checks were made early in the working day and again in the afternoon to look for dead or moribund animals.

BODY WEIGHT: Yes
The weight of each rat was recorded on day of arrival and on Days 6-20 after mating.
During the period of exposures, the bodyweights were recorded before exposure on the day.
Group mean values and SD were calculated for Days 4 and 6 to 20 of gestation for females with live young at Day 20. Weight changes were also calculated and plotted graphically with respect to Day 6 of gestation.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
The quantity of food comsumed by each cage of rats was recorded from the periods:
Days 2-5, 6-9, 10-13, 14-17 and 18-19 after mating.
Group mean values were calculated for days 2-5, 6-9, 10-13, 14-17 and 18-19 of pregnancy.

WATER CONSUMPTION: Yes
The quantity of water comsumed by each cage of rats was recorded on a daily basis, commencing from Day 2.
Group mean values were calculated for days 2-19 of pregnancy.

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 20
- Organs examined: the reproductive tract, complete with ovaries.
Each animal was first examined macroscopically for evidence of disease or adverse reaction to treatment and specimens of tissues considered to be abnormal were retained.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Number of corpora lutea: Yes (assessed in each ovary before removal)
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- Number and distribution of fetuses in each uterine horn.

Fetal examinations:

Each fetus was weighed, sexed and examined for any macroscopic external abnormalities. Individual placental weights and placental abnormalities were recorded.

The neck and the thoracic and abdonimal cavities of approximately half of the fetus of each litter were dissected and examined. fetal abnormalities were recorded and the fetus eviscerated prior to fixation in Industrial Methylated Spirit. After fixation, the fetuses were processed, stained with Alizarin and Red and skeletal development and abnormalities assessed.

The remained fetuses in each litter were placed in Bouin's fixative, subjected to free-hand serial sectioning and examined for visceral abnormalities.

The numbers of affected fetuses and the litters in which an observation occurred were reported for each group.

Data processing for fetuses at skeletal or visceral examination following free-hand serial sectioning was performed as following:
Structural changes are presented as major abnormalities, minor abnormalities and variants, classified according to severity and incidence as:
- Major abnormalities: rare and/or probably lethal changes e.g folded retina.
- Minor abnormalities: minor differences from "normal" that are detected relatively frequently either by skeletal examination or following free-hand serial sectioning e.g. cervical rib, variation in eye size.
- Variants: alternative structure occurring regurarly in the Control population e.g. incomplete ossification of 5th and 6th sternebrae.

Statistics:

Data relating to food and water consumption were analysed on a cage basis. For all other parameters the analysis were performed using the individual animal as the experimental unit. Bodyweight data were analysed using weight gains.
A sequence of statistical analysis was used for bodyweight, food and water consumption and litter/fetal data.
Details on the sequence of statistical analysis are reported in the section "Any other information on materials and method".

Indices:

LITTER RESPONSE
Litter data group mean values and SD (where appropriate) were calculated for number of corpora lutea, implantations, resorptions (early, late and total) and live youngs (male, female and total) at Day 20 of gestation. The group mean sex ratio (percentage of males) was also calculated.
Pre-natal losses were considered separately for the pre- and post- implantation phases.

- Pre-implanation loss:
Pre-implanation loss was calculated from the formula: [ (Number of corpora lutea - Number of implantations) / Number of corpora lutea ] x 100

- Post-implanation loss:
Post-implanation loss was calculated from the formula: [ (Number of implanations - Number of live fetus) / Number of implanations ] x 100

Group values were calculated using litter mean values. The number of implantations was substituted for the corpora lutea copunt in calculating pre-implantation loss where the number of implantations exceeded the corpora lutea count.

GROUP MEAN FETAL, LITTER AND PLACENTAL WEIGHTS
Group mean fetal and placental weights and SD were calculated for each group as:
(Total individual litter mean fetal or placental weights) / (Number of litters )

Mean fetal weights and SD were also calculated for each sex.

Group mean litter weights and SD were calculated for each group as:
(Total individual litter weights) / (Number of litters )

Historical control data:

not applied

Clinical signs:

no effects observed

Description (incidence and severity):

There were no adverse signs seen during the course of the study.

Mortality:

no mortality observed

Description (incidence):

There were no unscheduled deaths.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Group mean bodyweight gain of High dose females was transiently lower than the concurrent control group following the start of treatment.
Differences in bodyweight gain were -29.4% at day 9; -20.0% at day 10; -14.7% at day 11; -12.5% at day 12; -11.4% at day 13; -12.0% at day 14.
Although these difference were statistically significant, from mid-pregnancy the rate of bodyweight gain in the High dose group exceeded that of the Controls such that, by termination, overall bodyweight change was similar in these two groups.
There were no effects on bodyweight change in the Low and Intermediate dose goups.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Following the start of treatment group mean food consumption was slightly yet statistically significantly lower than the controls in High dose females. This effect tended to correlate with the effect on bodyweight. There were no effects on group mean food consumption in the Low or Intermediate dose groups.
Food consumption amongst the High dose animals reflected the pattern of bodyweight change. These changes are considered to be very slight and not to reflect any adverse effect of treatment.

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

effects observed, treatment-related

Description (incidence and severity):

Group mean water consumption of High dose was marginally greater than the Control during the majority of the treatment period (from Day 10), but since the overall difference was less than 5%, this is considered to be of no toxicological significance.

Gross pathological findings:

no effects observed

Description (incidence and severity):

There were no macroscopic changes detected at post mortem examination of the females on Day 20 of pregnancy.

Pre- and post-implantation loss:

no effects observed

Description (incidence and severity):

There were no treatment-related effects on the number of implantations or subsequent litter size. Implantation losses were low and there was no evidence of the selective loss of either sex, as evidenced by a similar sex ratio in all groups.

Total litter losses by resorption:

no effects observed

Dead fetuses:

no effects observed

Description (incidence and severity):

All females had live fetuses at Day 20.
The number of fetuses per litter is reported in the table below.

Other effects:

no effects observed

Description (incidence and severity):

placental weights were unaffected by treatment.

Details on maternal toxic effects:

Maternal toxic effects: no effects

Details on maternal toxic effects:
Amongst females exposed to 10006 ppm, there was a transient slightly lower bodyweight gain following the start of treatment when compared to the controls. (Differences in bodyweight gain were -29.4% at day 9; -20.0% at day 10; -14.7% at day 11; -12.5% at day 12; -11.4% at day 13; -12.0% at day 14). Athough these difference were statistically significant, bodyweight gain of these treated females exceeded the one of the controls from mid-pregnancy such that, by termination, overall bodyweight gain in the High dose group and the Control were similar.
Food consumption amongst the High dose animals reflected the pattern of bodyweight change. These changes are considered to be very slight and not to reflect any adverse effect of treatment.
There were no maternal effects upon animals exposed to 1004 or 3267 ppm.

Key result

Dose descriptor:

NOAEC

Effect level:

10 006 ppm (analytical)

Based on:

test mat.

Basis for effect level:

body weight and weight gain

Key result

Dose descriptor:

NOEC

Effect level:

3 267 ppm (analytical)

Based on:

test mat.

Basis for effect level:

body weight and weight gain

Key result

Abnormalities:

no effects observed

Fetal body weight changes:

no effects observed

Description (incidence and severity):

Fetal weights were unaffected by treatment.

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

no effects observed

Description (incidence and severity):

There were no treatment-related effects on the number of implantations or subsequent litter size.
Litter weights were unaffected by treatment.

External malformations:

no effects observed

Description (incidence and severity):

There were no gross macroscopic changes detected at external examination of fetuses from females killed on Day 20 of pregnancy.

Skeletal malformations:

no effects observed

Description (incidence and severity):

The incidence of major abnormalities, skeletal abnormalities and skeletal variants were low and showed no relationship to the treatment.

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

There was an increased incidence of displaced testis in the highest dosage group, but given the isolated nature of this findings the involvement of H GALDEN in its development is considered unlikely.

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects: no effects

Details on embryotoxic / teratogenic effects:
There were no effects of maternal exposure on litter parameters (survival and growth) or on the pattern of abnormalities amongst the fetuses at Day 20 post-coitum. A slightly higher incidence amongst the High dose group, of displaced testis (Incidence of displaced testes, High dose group = 5.91 %, Control group = 1.79 %) was considered to be unrelated to treatment due to the isolated nature of the findings, and the lack of any other related changes.

Key result

Dose descriptor:

NOAEC

Effect level:

10 006 ppm (analytical)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No substance-related adverse effects were observed at the highest tested dose.

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Abnormalities:

effects observed, non-treatment-related

Localisation:

visceral/soft tissue: male reproductive system

Description (incidence and severity):

A slightly higher incidence amongst the High dose group, of displaced testis (Incidence of displaced testes, High dose group = 5.91 %, Control group = 1.79 %) was considered to be unrelated to treatment due to the isolated nature of the findings, and the lack of any other related changes.

Key result

Developmental effects observed:

no

Implantations and litter size

concentration (analytical)		0	1004 ppm	3267 ppm	10006 ppm
number of females		25	25	25	25
Corpora lutea	mean SD	15.9 2.6	16.2 1.7	15.1 2.3	15.0 1.7
Implantations number	mean SD	14.4 1.8	14.7 1.6	13.8 2.9	14.2 1.8
Resorptions Total Early Late	mean mean mean	0.8 0.8 0.0	1.0 1.0 0.0	0.6 0.6 0.0	0.7 0.7 0.0
Live young Total	mean SD	13.6 1.9	13.6 2.1	13.2 3.1	13.5 1.9
Male	mean SD	7.2 2.2	7.2 2.4	6.4 2.2	6.5 2.4
Female	mean SD	6.4 2.4	6.4 2.1	6.8 2.6	7.0 2.2
Sex ratio (% males/litter)		53.5	52.7	49.0	47.7
Pre-implantation loss (%)		9.4	9.2	8.9	5.7
Post-implantation loss (%)		5.6	7.01	5.3	4.8

SD: standard deviation

no statistical differences (p>0.05)

Litter data

concentration (analytical)	0	1004 ppm	3267 ppm	10006 ppm
# of litters	25	25	25	25
# of live fetuses	339	341	329	337
mean litter weight (g) SD	50.81 7.72	51.28 8.60	49.57 11.19	51.11 7.38
mean fetal weight (g) (M+F) SD	3.75 0.23	3.75 0.21	3.78 0.23	3.79 0.16

Conclusions:

No treatment related effects were noted both in adult females and in fetuses. The no-observed-effect concentration (NOAEC) for maternal exposure to H GALDEN and embryo-fetal development in rats is 10006 ppm.

Executive summary:

Under the conditions of the reported study H GALDEN was administered to pregnant female CD rats by inhalation, during the organogenesis phase of the pregnancy.

Three groups, each of 25 time-mated female rats, were exposed to an aerosol of H GALDEN, 6 hours a day, from days 6-19 after mating using a whole body exposure system. A fourth group, also of 25 females, acted as a control and was exposed to air only. The target dose of H GALDEN were 1000, 3300 and 10000 ppm.

During the study clinical signs, bodyweight, food and water consumption were recorded. On day 20 of pregnancy the animals were killed, examined macroscopically, and the uterus excised for examination of litter parameters and subsequent fetal examination.

 

The exposure chamber mean analysed concentration over the duration of the study were 0 (Control), 1004, 3267, and 10006 ppm.

 

There were no treatment related clinical observations and no deaths amongst adult females.

Bodyweight gain and food consumption of the High dose females was slightly lower than that of the control during the first few days of treatment. Bodyweight gain recovered thereafter such that, overall, the gain was similar to the controls. These changes are very slight and considered not to reflect an adverse effect.

No treatment related effects were noted.

No treatment related macroscopic changes were noted.

There were no obvious effects on treatment on the in-utero parameters investigated.

There were considered no treatment related findings at detailed visceral and skeletal examination.

It was concluded that the maternal no-observable-effect concentration (NOAEC) for maternal exposure to H GALDEN and embryo-fetal development in rats is 10006 ppm.

 

Cross-reference 4

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

developmental toxicity

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH: see document attached

Reason / purpose for cross-reference:

read-across source

GLP compliance:

yes

Limit test:

no

Key result

Dose descriptor:

NOAEC

Effect level:

10 006 ppm (analytical)

Based on:

test mat.

Basis for effect level:

body weight and weight gain

Key result

Abnormalities:

no effects observed

Key result

Dose descriptor:

NOAEC

Effect level:

10 006 ppm (analytical)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No substance-related adverse effects were observed at the highest tested dose.

Key result

Abnormalities:

effects observed, non-treatment-related

Key result

Developmental effects observed:

no

Conclusions:

No treatment related effects were noted both in adult females and in fetuses in the study conducted with the analogue substance. The no-observable-effect concentration (NOAEC) for maternal exposure to H GALDEN and embryo-fetal development in rats is 10006 ppm.
Based on the analogue approach, GALDEN LMW is not expected to impair embryo-fetal development and the NOAEC of 10006 ppm can be considered a worst case for assessment.

Executive summary:

The read-across approach with the analogue substance H-GALDEN was applied in order to assess the potential effects on embryo-fetal survival and development of GALDEN LMW following exposure by inhalation. 

GALDEN LMW and H GALDEN have similar chemical structure and common characteristic which are typical of compound having C-F bounds. However the presence of –OCF2H as terminal groups in H-GALDEN, gives to the product slight more reactivity and more polarity than those observed for GALDEN, characterised by neutral, non functional terminal groups –OCF3.

The available experimental data show that GALDEN LMW and H GALDEN have the same profile regarding physico-chemical reactivity, skin and eye irritation and skin sensitization.

 

Under the reported study H GALDEN was administered to pregnant female CD rats by inhalation, during the organogenesis phase of the pregnancy.

Three groups, each of 25 time-mated female rats, were exposed to an aerosol of H GALDEN, 6 hours a day, from days 6-19 after mating using a whole body exposure system. A fourth group, also of 25 females, acted as a control and was exposed to air only. The target dose of H GALDEN were 1000, 3300 and 10000 ppm.

During the study clinical signs, bodyweight, food and water consumption were recorded. On day 20 of pregnancy the animals were killed, examined macroscopically, and the uterus excised for examination of litter parameters and subsequent fetal examination.

 

The exposure chamber mean analysed concentration over the duration of the study were 0 (Control), 1004, 3267, and 10006 ppm.

 

There were no treatment related clinical observations and no deaths amongst adult females.

Bodyweight gain and food consumption of the High dose females was slightly lower than that of the control during the first few days of treatment. Bodyweight gain recovered thereafter such that, overall, the gain was similar to the controls. These changes are very slight and considered not to reflect an adverse effect.

No treatment related effects were noted.

No treatment related macroscopic changes were noted.

There were no obvious effects on treatment on the in-utero parameters investigated.

There were considered no treatment related findings at detailed visceral and skeletal examination.

It was concluded that the maternal no-observable-effect concentration (NOAEC) for maternal exposure to H GALDEN and embryo-fetal development in rats is 10006 ppm.

 

Based on the analogue approach GALDEN LMW is expected to have the same toxicological profile as H GALDEN, therefore it is not expected to impair embryo-fetal developmental and the NOAEC of 10006 ppm for effects on embryo-fetal developmental and maternal toxicity can be considered as a worst case.

Moreover it should be underlined that, because of the greater reactivity of H GALDEN, the reported read across represents a worst case approach and it allows to be on the safe side in regard to the potential effects of GALDEN LMW on embryo-fetal development.

Materials and methods

Principles of method if other than guideline:

Expert judgment based on the assessment of data from 28-days (on Galden LMW), 90-days and Embryo-Fetal toxicity (as read across on analogues substance)

Test material

Test material information

Constituent 1

Reference substance name:

Hexafluoropropene, oxidized, oligomers, reduced, fluorinated

EC Number:

500-537-5

EC Name:

Hexafluoropropene, oxidized, oligomers, reduced, fluorinated

Cas Number:

161075-00-9

Molecular formula:

R-O(C3F6O)m-R with R= - CF3, - C2F5, -CF2H

IUPAC Name:

1,1,1,2,3,3-hexafluoro-2,3-bis(1,1,2,2,2-pentafluoroethoxy)propane; 1,1,1,2,3,3-hexafluoro-2-(1,1,2,2,2-pentafluoroethoxy)-3-(trifluoromethoxy)propane; 1,1,1,2,3,3-hexafluoro-3-(1,1,2,2,2-pentafluoroethoxy)-2-(trifluoromethoxy)propane; 1,1,1,2,3,3-hexafluoro-3-{[1,1,1,2,3,3-hexafluoro-3-(trifluoromethoxy)propan-2-yl]oxy}-2-(trifluoromethoxy)propane; 1,1,1,3,3,4,6,6,7,9,9,10,12,12,12-pentadecafluoro-4,7,10-tris(trifluoromethyl)-2,5,8,11-tetraoxadodecane; 1-(difluoromethoxy)-1,1,2,3,3,3-hexafluoro-2-(1,1,2,2,2-pentafluoroethoxy)propane; 2,2,3,5,5,6-hexafluoro-3,6-bis(trifluoromethyl)-1,4-dioxane; 2-(difluoromethoxy)-1,1,1,2,3,3-hexafluoro-3-(1,1,2,2,2-pentafluoroethoxy)propane

Results and discussion

Overall reproductive toxicity

Reproductive effects observed:

no

Applicant's summary and conclusion

Conclusions:

On the ground of read across and weight of evidence procedures, the available data support the low concern for effects on the reproduction and fertility for the fluoropolyether GALDEN LMW.

Executive summary:

Basing on the indications of the Integration Testing Strategy as reported in section R.7.6 a weight of evidence approach is proposed for the specific endpoints covering the reproduction and developmental toxicity.

The weight of evidence assessment should consider all the toxicity endpoints together, thus, the present WoE is based on:

 

1. the experimental studies available on H-Galden (see RAAF document):

 -13 week inhalation toxicity study (OECD413)

- Prenatal developmental toxicity study (inhalation route) (OECD414)

 

2. experimental animal study available on the substance itself, Galden LMW:

 - 4 week oral toxicity study with a 2 -week recovery period (OECD 407)

 

The “Endpoint specific guidance – R.7A, section R.7.6” by ECHA states that reproductive toxicity is characterized by multiple endpoints, which relate to impairment of male and female reproductive functions or capacity (fertility) and the induction of non-heritable harmful effects on the progeny (developmental toxicity).

 

As far as reproductive developmental toxicity is concerned, the read-across approach with the analogue substance H-Galden (see Annex I) was applied in order to assess

the potential effects on embryo-foetal survival and development of Galden LMW following exposure by inhalation.

Galden LMW and H-Galden have similar chemical structure and common characteristic which are typical of compound having C-F bounds. However the presence of –OCF2H as terminal groups in H-Galden, gives to the product slight more reactivity than those observed for Galden LMW, characterized by neutral, non functional terminal groups –OCF3.

The selected key-study for this endpoint is OECD 414 Guideline-conform, the experimental procedure permits to assess exhaustively the effects of the test substance on implantation, resorptions, foetal growth, morphological variations and malformations.

In particular, on day 20 after mating, females were sacrificed and their reproductive tract, complete with ovaries, was dissected for determination of the number of corpora lutea in each ovary, the number of implantation sites, the number of resorption sites and the number and distribution of fetuses in each uterine horn. Placental weights were measured, too.

No treatment-related effects on the number of implantations or placental weights were observed. Implantation losses were low and there was no evidence of the selective loss of either sex, as evidenced by a similar sex ratio in all groups.

On the whole, no treatment related effects were observed and the NOAEL of 10006 ppm for effects on embryo-foetal developmental and maternal toxicity was derived.

In conclusion, on the ground of read across approach as stated in Annex I and basing on the data reported above, Galden LMW is not expected to impair embryo-fetal development.

 

In the “Endpoint specific guidance – R.7A, section R.7.6” by ECHA fertility is defined in terms of male and female reproductive functions or capacity.

In particular, effects on male or female fertility include adverse effects on libido, sexual behaviour, any aspect of spermatogenesis or hormonal or physiological response, which would interfere with the capacity to fertilise, fertilisation itself or the development of the fertilised ovum up to and including implantation.

According to the testing strategy for reproductive toxicity from ECHA “Endpoint specific guidance – R.7A, section R.7.6” the observation of no adverse effects on the reproductive organs in a repeated-dose toxicity study, may justify a lower priority for further testing for effects on fertility.

In the sub-chronic OECD 413 toxicity study by inhalation administration to CD rats conducted on H-Galden, relative weights, dimensions and appearance of testes, ovaries, epididymides and uterus with cervix were determined.

The relative weights of these organs did not show any substance related effect and the macroscopic examinations revealed no changes attributable to treatment with H-Galden. Epididymides, ovaries, testes and uterus with cervix were subsequently examined microscopically for the control and high dose groups. No findings were observed for these organs.

In the sub-acute toxicity study on Galden LMW, after oral administration, there was no effect on relative weights, dimensions and appearance of testes or ovaries.

The Weight of Evidence assessment is the pooling of information from several in vivo reproductive and repeated toxicity studies. Individually, these studies may have deficiencies. However, taking account of the reliability and relevance and consistency of findings, collectively these studies could provide an adequate level of information leading to and appropriate classification decision and risk assessment.        

 

On the basis of the overall above considerations, available data to support a low concern for Galden LMW regarding effects on reproduction and developmental toxicity.