Registration Dossier

Toxicological information

Developmental toxicity / teratogenicity

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Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2015-07-30 to 2016-02-23
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
A discussion and report on the read across strategy is given as an attachment in Section 13.
Cross-referenceopen allclose all
Reason / purpose:
read-across: supporting information
Reference
Endpoint:
developmental toxicity
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
2015-07-30 to 2016-02-23
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
A discussion and report on the read across strategy is given as an attachment in Section 13.
Reason / purpose:
read-across source
Reason / purpose:
reference to same study
Remarks:
Section 7.5.1.
Clinical signs:
no effects observed
Description (incidence and severity):
No clinical signs of toxicity were detected.

One female in the 7500 ppm dietary group had generalised scab formation between gestation days 1 and 6. This was present before the start of test item administration and therefore unrelated to treatment.
Mortality:
no mortality observed
Description (incidence):
There were no unscheduled deaths.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
Females fed diet containing 7500 or 5000 ppm showed a reduction in body weight gain between gestation days 3, 4, 5, 8, 14 and 17. Although statistical significance was not achieved, actual body weight losses were evident between gestation days 3 and 4. Consequently, overall body weight gains were statistically significantly reduced (p<0.05-0.001) in females fed diet with 7500 ppm from gestation day 8 and in females fed diet with 5000 ppm from gestation day 17 (p<0.05). Body weight gain when adjusted for gravid uterus weight was also statistically significantly reduced (p<0.05) in females fed diet containing 7500 ppm. No adverse effects were detectedin body weight development for females fed diet containing 2500 ppm.
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
Females fed diet containing 7500 ppm showed a statistically significant reduction (p<0.01-0.001) in food consumption between gestation days 3 and 11. Recovery was evident thereafter. Females fed diet containing 5000 ppm showed a statistically significant reduction (p<0.05) in food consumption between gestation days 5 and 8. Food consumption for these females during the remaining periods were comparable to controls. No adverse effects were detected in food consumption for females fed diet containing 2500 ppm.
Water consumption and compound intake (if drinking water study):
no effects observed
Description (incidence and severity):
Daily visual inspection of water bottles did not reveal any overt intergroup differences.
Gross pathological findings:
no effects observed
Description (incidence and severity):
No abnormalities were detected during the macroscopic examination of the pregnant females at termination on gestation day 20.
Number of abortions:
no effects observed
Pre- and post-implantation loss:
no effects observed
Description (incidence and severity):
There was no effect of maternal exposure to 2500, 5000 or 7500 ppm of the test item on litter data, as assessed by numbers of implantations, in-uteroo ffspring survival (as assessed by the mean numbers of early or late resorptions), live litter size, sex ratio and pre and post implantation losses.
Total litter losses by resorption:
no effects observed
Description (incidence and severity):
There was no effect of maternal exposure to 2500, 5000 or 7500 ppm of the test item on litter data, as assessed by numbers of implantations, in-utero offspring survival (as assessed by the mean numbers of early or late resorptions), live litter size, sex ratio and pre and post implantation losses.
Early or late resorptions:
no effects observed
Description (incidence and severity):
There was no effect of maternal exposure to 2500, 5000 or 7500 ppm of the test item on litter data, as assessed by numbers of implantations, in-utero offspring survival (as assessed by the mean numbers of early or late resorptions), live litter size, sex ratio and pre and post implantation losses.
Description (incidence and severity):
Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): no effects observed
Description (incidence and severity):
At the 7500 ppm dietary exposure level, mean foetal weights for both sexes and placental weights were statistically significantly reduced (p<0.01 and p<0.05 respectively). No similar effects on foetal or placental weights were detected at the 5000 or 2500 ppm dietary exposure levels.
Key result
Dose descriptor:
NOAEL
Effect level:
2 500 ppm
Based on:
test mat.
Basis for effect level:
body weight and weight gain
other: Systemic Toxicity
Remarks on result:
other: equivalent to a mean achieved dosage of 199.3 mg/kg bw/day
Key result
Abnormalities:
effects observed, treatment-related
Localisation:
placenta
Description (incidence and severity):
At the 7500 ppm dietary exposure level, placental weights were statistically significantly reduced ( p<0.05).
Fetal body weight changes:
effects observed, treatment-related
Description (incidence and severity):
At the 7500 ppm dietary exposure level, mean foetal weights for both sexes were statistically significantly reduced (p<0.01 and p<0.05 respectively). No similar effects on foetal weights were detected at the 5000 or 2500 ppm dietary exposure levels.
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
External malformations:
no effects observed
Description (incidence and severity):
Neither the type, incidence nor the distribution of findings observed during external examination of the foetuses at necropsy on gestation day 20 and subsequent detailed visceral and skeletal examination indicated any adverse effect of maternal dietary exposure to the test item on foetal development.
Skeletal malformations:
effects observed, non-treatment-related
Description (incidence and severity):
Neither the type, incidence nor the distribution of findings observed during external examination of the foetuses at necropsy on gestation day 20 and subsequent detailed visceral and skeletal examination indicated any adverse effect of maternal dietary exposure to the test item on foetal development.

A statistically significant reduction in the number of foetuses/litters showing incomplete ossification of the squamosal bone of the skull was evident at 7500 and 5000 ppm. There was also a statistically significant reduction in the number of foetuses/litters showing no ossification of the hyoid in the skull at 2500 and 7500 ppm and a statistically significant increase in the number of foetuses/litters showing dumb-bell shaped thoracic centrum at 5000 ppm. The group means of each of these skeletal findings were all within historical control ranges and in the absence of trueexposure related responses, the intergroup differences were considered to reflect normal biological variation. A statistically significant increase in the number of foetuses/litters showing ossification centre associated with 1st lumbar vertebra was evident at 2500, 5000 and 7500 ppm. The foetal/litter incidence of this finding was: 1/1; 13/8; 24/13; and 56/18 in the 0, 2500, 5000 and 7500 ppm groups respectively. The historical control range for this parameter was 4.9% to 13.7% and although group mean values at 5000 and 7500 ppm were above the historical control range, the control group mean incidence was significantly below the historical control range, with an atypically
lower value than expected for this parameter. This variation is indicative of precocious ossification, however it was seen in isolation of other developmental changes such as increased mean foetal weight. No other skeletal structures showed evidence of precocious ossification and there was evidence of only one skeletal structure showing delayed ossification (incomplete ossification of the squamosal bone of the skull). Consequently, this was considered to be an isolated finding which was not regarded as evidence of adverse developmental toxicity (Carney and Kimmel, 2007).
Visceral malformations:
no effects observed
Description (incidence and severity):
Neither the type, incidence nor the distribution of findings observed during external examination of the foetuses at necropsy on gestation day 20 and subsequent detailed visceral and skeletal examination indicated any adverse effect of maternal dietary exposure to the test item on foetal development.
Other effects:
effects observed, non-treatment-related
Description (incidence and severity):
One female at the lowest dietary exposure level (2500 ppm) had conjoined twin foetuses. In the absence of a similar effect at the higherexposure levels this finding was considered incidental and unrelated to treatment.

At the highest dietary exposure level (7500 ppm), a statistically significant reduction (p<0.05) in the foetal incidence of non-uniform patterning of the rugae was observed. A reduction in this parameter is considered not to be an adverse developmental effect.
Key result
Dose descriptor:
NOAEL
Effect level:
5 000 ppm
Based on:
test mat.
Sex:
male/female
Basis for effect level:
fetal/pup body weight changes
Remarks on result:
other: equivalent to a mean achieved dosage of 387.2 mg/kg bw/day
Key result
Abnormalities:
no effects observed
Key result
Developmental effects observed:
yes
Lowest effective dose / conc.:
5 000 ppm
Treatment related:
yes
Relation to maternal toxicity:
developmental effects as a secondary non-specific consequence of maternal toxicity effects
Dose response relationship:
yes
Relevant for humans:
not specified

Table 2. Group Mean Body Weight Change Values

Dietary Concentration (ppm)

 

 

Cumulative Body Weight Change (g) from Day 3 of Gestation

4

5

8

11

14

17

20

 

0 (Control)

Mean

2.4

4.7

22.3

43.0

63.3

92.4

140.0

SD

5.4

8.5

8.5

10.8

9.8

11.6

15.9

n

23

23

23

23

23

23

23

 

 

2500

Mean

1.1

5.3

20.6

42.4

63.2

88.8

134.7

SD

6.1

5.5

8.1

8.3

11.1

12.6

13.9

n

23

23

23

23

23

23

23

 

 

5000

Mean

-0.8

2.6

17.3

37.2

57.5

83.0*

126.3*

SD

7.6

7.3

10.7

10.5

9.0

13.3

21.3

n

24

24

24

24

24

24

24

 

 

7500

Mean

-1.3

0.1

14.5*

33.1**

51.3**

76.5***

122.8**

SD

7.7

8.9

10.1

10.5

14.2

15.5

19.3

n

24

24

24

24

24

24

24

Table 3. Group Mean Food Consumption Values

Dietary Concentration (ppm)

 

Food Consumption (g/rat/day)

between Days of Gestation

3-5

5-8

8-11

11-14

14-17

17-20

 

0 (Control)

Mean

15.9

22.3

24.7

24.3

27.1

27.2

SD

2.5

2.6

2.4

2.7

1.8

2.2

n

23

23

23

23

23

23

 

 

2500

Mean

16.6

21.2

24.1

24.8

26.8

26.7

SD

2.4

2.1

2.5

2.2

3.0

2.4

n

23

23

23

23

23

23

 

 

5000

Mean

14.0

19.7**

23.3

24.4

26.5

26.4

SD

2.8

3.1

2.5

1.9

2.4

2.7

n

24

24

24

24

24

24

 

 

7500

Mean

11.0***

19.2**

22.4**

23.0

26.0

26.1

SD

3.2

3.3

2.8

3.5

2.9

2.8

n

24

24

24

24

24

24

Table 4. Group Mean Litter Data Values

Dietary Concentration (ppm)

 

Mean Male

Foetal Weight (g)

Mean Female

Foetal Weight (g)

Mean Foetal

Weight (g)

Mean

Placental

Weight (g)

 

0 (Control)

Mean

4.012

3.826

3.922

0.640

SD

0.272

0.233

0.244

0.080

n

23

23

23

23

 

 

2500

Mean

3.925

3.756

3.840

0.626

SD

0.229

0.241

0.231

0.100

n

23

23

23

23

 

 

5000

Mean

3.952

3.742

3.855

0.694

SD

0.304

0.308

0.289

0.144

n

24

24

24

24

 

 

7500

Mean

3.712**

3.550**

3.635**

0.559**

SD

0.313

0.329

0.309

0.079

n

24

24

24

24

Conclusions:
The oral administration of Rosin CAS 8050-09-7 to pregnant rats by continuous dietary exposure during gestation days 3 to 19, at concentrations of 2500, 5000 or 7500 ppm was associated with lower maternal body weight gain during gestation and an initial effect on food consumption at 7500 ppm and lower maternal body weight gain at 5000 ppm. No similar effects were apparent at 2500 ppm (equivalent to a mean achieved dosage of 199.3 mg/kg bw/day) which was considered to represent the No Observed Adverse Effect Level (NOAEL) for the pregnant female.

In-utero survival of the developing conceptus was unaffected by maternal exposure at 7500 ppm, although reduced foetal and placental weights indicated an adverse effect on foetal growth. The absence of any structural defects indicated that development per se was unaffected at this dietary exposure level. At 5000 or 2500 ppm no adverse treatment-related changes were detected in the offspring parameters measured or on embryofoetal development. The ‘No Observed Adverse Effect Level’ (NOAEL) for foetal developmental toxicity was therefore considered to be 5000 ppm (equivalent to a mean achieved dosage of 387.2 mg/kg bw/day).
Executive summary:

In a key pre-natal developmental toxicity study, the test material (Rosin, CAS# 8050-09-7) was administered by continuous dietary admixture to three groups each composed of twenty-four time mated Sprague-Dawley Crl:CD®(SD) IGS BR strain rats, between gestation days 3 and 19 (inclusive) at dietary concentrations of 2500, 5000, or 7500 ppm (equivalent to mean achieved dosages of 199.3, 387.2 or 561.1 mg/kg bw/day respectively). A further group of twenty-four time mated females was fed basal laboratory diet to serve as a control.

 

Clinical signs, body weight change, food and water consumptions were monitored during the study. All females were terminated on gestation day 20 and subjected to gross necropsy including examination of the uterine contents. The number of corpora lutea, number, position and type of implantation, placental weights, foetal weight, sex and external and internal macroscopic appearance were recorded. Half of the pups from each litter were examined for detailed skeletal development and the remainder were subjected to detailed visceral examination.

 

The oral administration of the test material to pregnant rats by continuous dietary exposure was associated with lower maternal body weight gain during gestation and an initial effect on food consumption at 7500 ppm and lower maternal body weight gain at 5000 ppm. No similar effects were apparent at 2500 ppm (equivalent to a mean achieved dosage of 199.3 mg/kg bw/day) which was considered to represent the No Observed Adverse Effect Level (NOAEL) for the pregnant female.

 

In-utero survival of the developing conceptus was unaffected by maternal exposure at 7500 ppm, although reduced foetal and placental weights indicated an adverse effect on foetal growth. The absence of any structural defects indicated that development per se was unaffected at this dietary exposure level. At 5000 or 2500 ppm no adverse treatment-related changes were detected in the offspring parameters measured or on embryofoetal development. The ‘No Observed Adverse Effect Level’ (NOAEL) for foetal developmental toxicity was therefore considered to be 5000 ppm (equivalent to a mean achieved dosage of 387.2 mg/kg bw/day).

Reason / purpose:
reference to same study
Remarks:
Section 7.5.1.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 414 (Prenatal Developmental Toxicity Study)
Deviations:
yes
Remarks:
deviations had no adverse impact on the scientific purpose of the study.
GLP compliance:
yes (incl. certificate)
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid

Test animals

Species:
rat
Strain:
Sprague-Dawley
Remarks:
Crl:CD (SD) IGS BR strain
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River (UK) Limited,Margate, Kent.
- Age at study initiation: Not specified
- Weight at study initiation: 181 to 302g.
- Fasting period before study: Not specified
- Housing: The animals were housed individually in solid-floor polypropylene cages with stainless steel mesh lids furnished with softwood flakes (Datesand Ltd., Cheshire, UK).
- Diet (e.g. ad libitum): Ground diet (Rodent PMI 5002 (Certified), BCM IPS Limited, London, UK) was used ad libitum
- Water (e.g. ad libitum): Mains drinking water was supplied ad libitum from polycarbonate bottles attached to the cage
- Acclimation period: Not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 ºC
- Humidity (%): 50 ± 20%
- Air changes (per hr): at least fifteen air changes per hour
- Photoperiod (hrs dark / hrs light): low intensity fluorescent lighting was controlled to give twelve hours continuous light and twelvehours darkness

IN-LIFE DATES: From: 2015-09-25 To: 2015-10-14

Administration / exposure

Route of administration:
oral: feed
Vehicle:
unchanged (no vehicle)
Details on exposure:
DIET PREPARATION
- Rate of preparation of diet (frequency): Dietary admixtures were prepared once and stored at room temperature
- Mixing appropriate amounts with (Type of food): A known amount of test item was mixed with a small amount of basal laboratory diet in a Robot Coupe Blixer 4 mixer until homogeneous. This pre-mix was then added to a larger amount of basal laboratory diet and mixed for a further sixty minutes at a constant speed, setting 1 in a Hobart H800 mixer.
- Storage temperature of food: stored at room temperature
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
The stability and homogeneity of the dietary admixtures were determined by Envigo Research Limited (Shardlow, UK, Analytical Services). Dietary admixtures were prepared once and stored at room temperature. Samples were taken and analyzed for
concentration of Rosin CAS 8050-09-7 at Envigo Research Limited (Shardlow, UK, Analytical Services). The results indicate that the prepared formulations were within 101% to 110% of the nominal concentration confirming the suitability and accuracy of the formulation procedure.
Details on mating procedure:
A total of ninety-six time-mated female Sprague-Dawley Crl:CD(SD) IGS BR strain rats were obtained from Charles River (UK) Limited,Margate, Kent. Animals were delivered in two batches containing females prior to Day 3 of gestation. The day that positive evidence of mating was observed was designated Day 0 of gestation.
Duration of treatment / exposure:
From gestation day 3 to 19.
Frequency of treatment:
Continuously administered in the diet
Duration of test:
From gestation day 3 to 19.
Doses / concentrationsopen allclose all
Dose / conc.:
0 ppm
Remarks:
Control
Dose / conc.:
2 500 ppm
Remarks:
Low (equivalent to 199.3 mg/Kg bw/day)
Dose / conc.:
5 000 ppm
Remarks:
Intermediate (equivalent to 387.2 mg/Kg bw/day)
Dose / conc.:
7 500 ppm
Remarks:
High (equivalent to 561.1 mg/Kg bw/day)
No. of animals per sex per dose:
24/concentration
Control animals:
yes, concurrent no treatment
Details on study design:
- Dose selection rationale: The dose levels were chosen based on previous toxicity data (Harlan Laboratories Ltd., Study Number D80926: Tall Oil Rosin-CAS No. 8050-09-7: Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test in the Han Wistar Rat).
- Rationale for animal assignment (if not random): The animals were randomly allocated to treatment groups using a randomization procedure based on stratified body weight to ensure similarity between the treatment groups. The animals were uniquely identified within the study by an ear punching system routinely used in these laboratories.

Examinations

Maternal examinations:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Following arrival, all animals were examined for overt signs of toxicity, ill-health or behavioural changes once daily during the gestation period.

BODY WEIGHT: Yes
- Time schedule for examinations: Individual body weights were recorded on gestation days 3, 4, 5, 8, 11, 14, and 17. Body weights were also recorded for animals at terminal kill (Day 20).

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
Food consumption was recorded for each individual animal on gestation days 3, 5, 8, 11, 14, 17 and 20.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes
- Time schedule for examinations: Water intake was observed daily by visual inspection of the water bottles for any overt changes.

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day # 20
All animals were killed by carbon dioxide asphyxiation followed by cervical dislocation on Day 20 of gestation. All animals were subjected to a full external and internal examination and any macroscopic abnormalities were recorded.
Ovaries and uterine content:
The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- Other:
i) Number, position and type of intrauterine implantation
ii) Foetal sex
iii) External foetal appearance
iv) Foetal weight
v) Placental weight
Fetal examinations:
- External examinations: Yes: [all per litter ]
- Soft tissue examinations: Yes: [all per litter]
- Skeletal examinations: Yes: [all per litter]
- Head examinations: Yes: [all per litter]
Statistics:
The following parameters wereanalysed statistically, where appropriate, using the test methods outlined below:
Female body weight change, food consumption and gravid uterus weight: Shapiro Wilk normality test and Bartlett’s test for homogeneity of variance and one way analysis of variance, followed by Dunnett’s multiple comparison test or, if unequal variances were observed, on alternative multiple comparison test. All caesarean necropsy parameters and foetalparameters: Kruskal-Wallis non-parametric analysis of variance; and a subsequent pairwise analysis of control values against treated values using the Mann-Whitney ‘U’ test, where significance was seen. Foetal evaluation parameters, including skeletal or visceral findings: Kruskal-Wallis nonparametric analysis of variance and Mann-Whitney ‘U’ test.
Probability values (p) are presented as follows:
p<0.001 ***
p<0.01 **
p<0.05 *
p≥0.05 (not significant)
Indices:
1) Pre and Post Implantation Loss: Percentage pre-implantation loss was calculated as:
((Number of Corpora Lutea - Number of Implantations)/(Number of Corpora Lutea)) x 100

2) Percentage post-implantation loss was calculated as:
((Number of Implantations - Number of live Foetuses)/(Number of Implantations)) x 100

3) Sex Ration: Sex ratio was calculated as:
% male foetuses (sex ratio) = (Number of Male Foetuses/Total Number of Foetuses) x 100

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:
no effects observed
Description (incidence and severity):
No clinical signs of toxicity were detected.

One female in the 7500 ppm dietary group had generalised scab formation between gestation days 1 and 6. This was present before the start of test item administration and therefore unrelated to treatment.
Mortality:
no mortality observed
Description (incidence):
There were no unscheduled deaths.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
Females fed diet containing 7500 or 5000 ppm showed a reduction in body weight gain between gestation days 3, 4, 5, 8, 14 and 17. Although statistical significance was not achieved, actual body weight losses were evident between gestation days 3 and 4. Consequently, overall body weight gains were statistically significantly reduced (p<0.05-0.001) in females fed diet with 7500 ppm from gestation day 8 and in females fed diet with 5000 ppm from gestation day 17 (p<0.05). Body weight gain when adjusted for gravid uterus weight was also statistically significantly reduced (p<0.05) in females fed diet containing 7500 ppm. No adverse effects were detectedin body weight development for females fed diet containing 2500 ppm.
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
Females fed diet containing 7500 ppm showed a statistically significant reduction (p<0.01-0.001) in food consumption between gestation days 3 and 11. Recovery was evident thereafter. Females fed diet containing 5000 ppm showed a statistically significant reduction (p<0.05) in food consumption between gestation days 5 and 8. Food consumption for these females during the remaining periods were comparable to controls. No adverse effects were detected in food consumption for females fed diet containing 2500 ppm.
Water consumption and compound intake (if drinking water study):
no effects observed
Description (incidence and severity):
Daily visual inspection of water bottles did not reveal any overt intergroup differences.
Gross pathological findings:
no effects observed
Description (incidence and severity):
No abnormalities were detected during the macroscopic examination of the pregnant females at termination on gestation day 20.

Maternal developmental toxicity

Number of abortions:
no effects observed
Pre- and post-implantation loss:
no effects observed
Description (incidence and severity):
There was no effect of maternal exposure to 2500, 5000 or 7500 ppm of the test item on litter data, as assessed by numbers of implantations, in-uteroo ffspring survival (as assessed by the mean numbers of early or late resorptions), live litter size, sex ratio and pre and post implantation losses.
Total litter losses by resorption:
no effects observed
Description (incidence and severity):
There was no effect of maternal exposure to 2500, 5000 or 7500 ppm of the test item on litter data, as assessed by numbers of implantations, in-utero offspring survival (as assessed by the mean numbers of early or late resorptions), live litter size, sex ratio and pre and post implantation losses.
Early or late resorptions:
no effects observed
Description (incidence and severity):
There was no effect of maternal exposure to 2500, 5000 or 7500 ppm of the test item on litter data, as assessed by numbers of implantations, in-utero offspring survival (as assessed by the mean numbers of early or late resorptions), live litter size, sex ratio and pre and post implantation losses.
Description (incidence and severity):
Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): no effects observed
Description (incidence and severity):
At the 7500 ppm dietary exposure level, mean foetal weights for both sexes and placental weights were statistically significantly reduced (p<0.01 and p<0.05 respectively). No similar effects on foetal or placental weights were detected at the 5000 or 2500 ppm dietary exposure levels.

Effect levels (maternal animals)

Key result
Dose descriptor:
NOAEL
Effect level:
2 500 ppm
Based on:
test mat.
Basis for effect level:
body weight and weight gain
other: Systemic Toxicity
Remarks on result:
other: equivalent to a mean achieved dosage of 199.3 mg/kg bw/day

Maternal abnormalities

Key result
Abnormalities:
effects observed, treatment-related
Localisation:
placenta
Description (incidence and severity):
At the 7500 ppm dietary exposure level, placental weights were statistically significantly reduced ( p<0.05).

Results (fetuses)

Fetal body weight changes:
effects observed, treatment-related
Description (incidence and severity):
At the 7500 ppm dietary exposure level, mean foetal weights for both sexes were statistically significantly reduced (p<0.01 and p<0.05 respectively). No similar effects on foetal weights were detected at the 5000 or 2500 ppm dietary exposure levels.
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
External malformations:
no effects observed
Description (incidence and severity):
Neither the type, incidence nor the distribution of findings observed during external examination of the foetuses at necropsy on gestation day 20 and subsequent detailed visceral and skeletal examination indicated any adverse effect of maternal dietary exposure to the test item on foetal development.
Skeletal malformations:
effects observed, non-treatment-related
Description (incidence and severity):
Neither the type, incidence nor the distribution of findings observed during external examination of the foetuses at necropsy on gestation day 20 and subsequent detailed visceral and skeletal examination indicated any adverse effect of maternal dietary exposure to the test item on foetal development.

A statistically significant reduction in the number of foetuses/litters showing incomplete ossification of the squamosal bone of the skull was evident at 7500 and 5000 ppm. There was also a statistically significant reduction in the number of foetuses/litters showing no ossification of the hyoid in the skull at 2500 and 7500 ppm and a statistically significant increase in the number of foetuses/litters showing dumb-bell shaped thoracic centrum at 5000 ppm. The group means of each of these skeletal findings were all within historical control ranges and in the absence of trueexposure related responses, the intergroup differences were considered to reflect normal biological variation. A statistically significant increase in the number of foetuses/litters showing ossification centre associated with 1st lumbar vertebra was evident at 2500, 5000 and 7500 ppm. The foetal/litter incidence of this finding was: 1/1; 13/8; 24/13; and 56/18 in the 0, 2500, 5000 and 7500 ppm groups respectively. The historical control range for this parameter was 4.9% to 13.7% and although group mean values at 5000 and 7500 ppm were above the historical control range, the control group mean incidence was significantly below the historical control range, with an atypically
lower value than expected for this parameter. This variation is indicative of precocious ossification, however it was seen in isolation of other developmental changes such as increased mean foetal weight. No other skeletal structures showed evidence of precocious ossification and there was evidence of only one skeletal structure showing delayed ossification (incomplete ossification of the squamosal bone of the skull). Consequently, this was considered to be an isolated finding which was not regarded as evidence of adverse developmental toxicity (Carney and Kimmel, 2007).
Visceral malformations:
no effects observed
Description (incidence and severity):
Neither the type, incidence nor the distribution of findings observed during external examination of the foetuses at necropsy on gestation day 20 and subsequent detailed visceral and skeletal examination indicated any adverse effect of maternal dietary exposure to the test item on foetal development.
Other effects:
effects observed, non-treatment-related
Description (incidence and severity):
One female at the lowest dietary exposure level (2500 ppm) had conjoined twin foetuses. In the absence of a similar effect at the higherexposure levels this finding was considered incidental and unrelated to treatment.

At the highest dietary exposure level (7500 ppm), a statistically significant reduction (p<0.05) in the foetal incidence of non-uniform patterning of the rugae was observed. A reduction in this parameter is considered not to be an adverse developmental effect.

Effect levels (fetuses)

Key result
Dose descriptor:
NOAEL
Effect level:
5 000 ppm
Based on:
test mat.
Sex:
male/female
Basis for effect level:
fetal/pup body weight changes
Remarks on result:
other: equivalent to a mean achieved dosage of 387.2 mg/kg bw/day

Fetal abnormalities

Key result
Abnormalities:
no effects observed

Overall developmental toxicity

Key result
Developmental effects observed:
yes
Lowest effective dose / conc.:
5 000 ppm
Treatment related:
yes
Relation to maternal toxicity:
developmental effects as a secondary non-specific consequence of maternal toxicity effects
Dose response relationship:
yes
Relevant for humans:
not specified

Any other information on results incl. tables

Table 2. Group Mean Body Weight Change Values

Dietary Concentration (ppm)

 

 

Cumulative Body Weight Change (g) from Day 3 of Gestation

4

5

8

11

14

17

20

 

0 (Control)

Mean

2.4

4.7

22.3

43.0

63.3

92.4

140.0

SD

5.4

8.5

8.5

10.8

9.8

11.6

15.9

n

23

23

23

23

23

23

23

 

 

2500

Mean

1.1

5.3

20.6

42.4

63.2

88.8

134.7

SD

6.1

5.5

8.1

8.3

11.1

12.6

13.9

n

23

23

23

23

23

23

23

 

 

5000

Mean

-0.8

2.6

17.3

37.2

57.5

83.0*

126.3*

SD

7.6

7.3

10.7

10.5

9.0

13.3

21.3

n

24

24

24

24

24

24

24

 

 

7500

Mean

-1.3

0.1

14.5*

33.1**

51.3**

76.5***

122.8**

SD

7.7

8.9

10.1

10.5

14.2

15.5

19.3

n

24

24

24

24

24

24

24

Table 3. Group Mean Food Consumption Values

Dietary Concentration (ppm)

 

Food Consumption (g/rat/day)

between Days of Gestation

3-5

5-8

8-11

11-14

14-17

17-20

 

0 (Control)

Mean

15.9

22.3

24.7

24.3

27.1

27.2

SD

2.5

2.6

2.4

2.7

1.8

2.2

n

23

23

23

23

23

23

 

 

2500

Mean

16.6

21.2

24.1

24.8

26.8

26.7

SD

2.4

2.1

2.5

2.2

3.0

2.4

n

23

23

23

23

23

23

 

 

5000

Mean

14.0

19.7**

23.3

24.4

26.5

26.4

SD

2.8

3.1

2.5

1.9

2.4

2.7

n

24

24

24

24

24

24

 

 

7500

Mean

11.0***

19.2**

22.4**

23.0

26.0

26.1

SD

3.2

3.3

2.8

3.5

2.9

2.8

n

24

24

24

24

24

24

Table 4. Group Mean Litter Data Values

Dietary Concentration (ppm)

 

Mean Male

Foetal Weight (g)

Mean Female

Foetal Weight (g)

Mean Foetal

Weight (g)

Mean

Placental

Weight (g)

 

0 (Control)

Mean

4.012

3.826

3.922

0.640

SD

0.272

0.233

0.244

0.080

n

23

23

23

23

 

 

2500

Mean

3.925

3.756

3.840

0.626

SD

0.229

0.241

0.231

0.100

n

23

23

23

23

 

 

5000

Mean

3.952

3.742

3.855

0.694

SD

0.304

0.308

0.289

0.144

n

24

24

24

24

 

 

7500

Mean

3.712**

3.550**

3.635**

0.559**

SD

0.313

0.329

0.309

0.079

n

24

24

24

24

Applicant's summary and conclusion

Conclusions:
The oral administration of Rosin CAS 8050-09-7 to pregnant rats by continuous dietary exposure during gestation days 3 to 19, at concentrations of 2500, 5000 or 7500 ppm was associated with lower maternal body weight gain during gestation and an initial effect on food consumption at 7500 ppm and lower maternal body weight gain at 5000 ppm. No similar effects were apparent at 2500 ppm (equivalent to a mean achieved dosage of 199.3 mg/kg bw/day) which was considered to represent the No Observed Adverse Effect Level (NOAEL) for the pregnant female.

In-utero survival of the developing conceptus was unaffected by maternal exposure at 7500 ppm, although reduced foetal and placental weights indicated an adverse effect on foetal growth. The absence of any structural defects indicated that development per se was unaffected at this dietary exposure level. At 5000 or 2500 ppm no adverse treatment-related changes were detected in the offspring parameters measured or on embryofoetal development. The ‘No Observed Adverse Effect Level’ (NOAEL) for foetal developmental toxicity was therefore considered to be 5000 ppm (equivalent to a mean achieved dosage of 387.2 mg/kg bw/day).
Executive summary:

In a key pre-natal developmental toxicity study, the test material (Rosin, CAS# 8050-09-7) was administered by continuous dietary admixture to three groups each composed of twenty-four time mated Sprague-Dawley Crl:CD®(SD) IGS BR strain rats, between gestation days 3 and 19 (inclusive) at dietary concentrations of 2500, 5000, or 7500 ppm (equivalent to mean achieved dosages of 199.3, 387.2 or 561.1 mg/kg bw/day respectively). A further group of twenty-four time mated females was fed basal laboratory diet to serve as a control.

 

Clinical signs, body weight change, food and water consumptions were monitored during the study. All females were terminated on gestation day 20 and subjected to gross necropsy including examination of the uterine contents. The number of corpora lutea, number, position and type of implantation, placental weights, foetal weight, sex and external and internal macroscopic appearance were recorded. Half of the pups from each litter were examined for detailed skeletal development and the remainder were subjected to detailed visceral examination.

 

The oral administration of the test material to pregnant rats by continuous dietary exposure was associated with lower maternal body weight gain during gestation and an initial effect on food consumption at 7500 ppm and lower maternal body weight gain at 5000 ppm. No similar effects were apparent at 2500 ppm (equivalent to a mean achieved dosage of 199.3 mg/kg bw/day) which was considered to represent the No Observed Adverse Effect Level (NOAEL) for the pregnant female.

 

In-utero survival of the developing conceptus was unaffected by maternal exposure at 7500 ppm, although reduced foetal and placental weights indicated an adverse effect on foetal growth. The absence of any structural defects indicated that development per se was unaffected at this dietary exposure level. At 5000 or 2500 ppm no adverse treatment-related changes were detected in the offspring parameters measured or on embryofoetal development. The ‘No Observed Adverse Effect Level’ (NOAEL) for foetal developmental toxicity was therefore considered to be 5000 ppm (equivalent to a mean achieved dosage of 387.2 mg/kg bw/day).