Registration Dossier

Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

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)
GLP compliance:
yes (incl. certificate)
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rat
Strain:
Sprague-Dawley
Details on test animals and environmental conditions:
Age/Weight: Timed-pregnant female rats were pregnant for the first time and
shipping schedule arranged to receive animals on GD1, 2, or 3, following confirmed
mating by the supplier. Animals were mated by the supplier at 10-11 weeks of age.
The confirmed day of pregnancy, provided by the supplier, was recorded in the raw
data. The weight variation did not exceed ± 20% of the mean weight.
Animal Room Temperature and Relative Humidity Ranges
The room temperature and humidity ranged from 19-23°C and 38-56%,
respectively.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
over a test period of implantation through gestation (GD5-19).
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
The dose preparations (test and control) were sampled at the beginning (as part of
the homogeneity assessment, Section 6.B.6) and again at the end of the study for
verification of dose concentration. Given that dose preparations were made
daily, maintained on a stir plate during dose administration, and used within
approximately 2 hours, the test substance in the preparation was considered to be
stable.
Details on mating procedure:
not metioned
Duration of treatment / exposure:
The test substance or vehicle control (corn oil) was administered daily (7 days/week) via oral
intubation to each rat during gestation days (GD) 5-19 of a 21-day pregnancy
Frequency of treatment:
The test substance or vehicle control (corn oil) was administered daily (7 days/week) via oral
intubation to each rat during gestation days (GD) 5-19 of a 21-day pregnancy
Doses / concentrationsopen allclose all
Dose / conc.:
0 other: mg/ml
Dose / conc.:
25 other: mg/ml
Dose / conc.:
62.5 other: mg/ml
Dose / conc.:
100 other: mg/ml
Dose / conc.:
0 mg/kg bw/day
Remarks:
dibenzoyl methane
Dose / conc.:
100 mg/kg bw/day
Remarks:
dibenzoyl methane
Dose / conc.:
250 mg/kg bw/day
Remarks:
dibenzoyl methane
Dose / conc.:
400 mg/kg bw/day
Remarks:
dibenzoyl methane
No. of animals per sex per dose:
20 timed-pregnant female rats per dose in total, there are 80 female rats
Control animals:
yes
Details on study design:
This study design was based on the following guidelines:
EPA Health Effects Test Guidelines. OPPTS 870.3700: Prenatal Developmental Toxicity
Study. EPA 712-C-98-207, August 1998.
 OECD Guidelines for Testing of Chemicals, Section 4, Test No. 414: Prenatal Developmental
Toxicity Study, adopted 22 January 2001.
 ICH Harmonized Tripartite Guideline, Detection of Toxicity to Reproduction for Medicinal
Products. Study for Effects on Embryo-Fetal Developmental (Segment II), S5(R2), Guideline
4.1.3.Step 4 version, 24 June 1993.

Examinations

Maternal examinations:
One Group 2 female (Animal 8024) was confirmed to be not pregnant by
ammonium sulfate staining, and one Group 4 female (Animal 8077) was found to
have total litter loss on GD20.
All other Group 1-4 females were confirmed pregnant, with viable pregnancies,
at scheduled sacrifice on GD20.
Ovaries and uterine content:
Gravid uterine weights were comparable between control and treated groups for all confirmed pregnant females carrying viable fetuses to GD20, and there were no test substance-related macroscopic findings or effects on the placentae.
Fetal examinations:
the (external) fetal male sex ratios, total mean litter weight, and number of
live fetuses per litter were comparable across treatment groups. Under the study conditions, the administration of Dibenzoyl methane resulted in no treatment-related
external, visceral or skeletal teratogenic effects.
Statistics:
Statistical Methods of the Parental (P) Generation: Mean and standard deviations were calculated for all quantitative data collected from dams.
When warranted by sufficient group sizes, data within groups were evaluated for homogeneity of
variances and normality by Bartlett’s test (Bartlett, 1937). Where Bartlett’s test indicated
homogeneous variances, treated and control groups were compared using a one-way analysis of
variance (ANOVA). When one-way analysis of variance was significant, a comparison of the
treated groups to control for multiple comparisons was performed by Dunnett’s test (Dunnett,
1964, 1980). Where variances were considered significantly different by Bartlett’s test, groups
were compared using a non-parametric method (Kruskal-Wallis non-parametric analysis of
variance; Kruskal and Wallis, 1952). When non-parametric analysis of variance was significant,
comparison of treated groups to control was performed using Dunn’s test (Dunn, 1964).
Statistical Methods of the Filial (F1) Generation
The litter was the experimental unit for evaluation where appropriate. Mean and standard
deviations were calculated independently for control and treatment groups. Similarly, mortality,
sex, along with skeletal and visceral changes were analyzed as number per litter. These analyses
were performed independently on control and the test groups. Inferential comparisons between
control and the test groups were made with regards to homogeneity of variance, normality, and
ANOVA, where appropriate.

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:
effects observed, non-treatment-related
Description (incidence and severity):
Maternal Examinations During Pregnancy:
Test substance-related clinical signs were noted in Group 4 animals and consisted
of: an increased incidence and/or severity in alopecia (8/20 animals) and anogenital
staining (6/20 animals); unilateral ocular discharge in 2/20 animals; slight
to moderate hypersalivation in 4/20 animals; and soft feces in 1/20 animals.
Corresponding detailed clinical observations included: hair loss in 5/20 animals;
lacrimation in 1/20 animals; salivation (above normal) in 1/20 animals; and
salivation (excessive) in 1/20 animals.
Incidental clinical signs noted during the study included: slight to moderate
alopecia on the left/right flank, forepaw/limb, and/or back of 2/20 Group 1, 2/20
Group 2, and 1/20 Group 3 animals; superficial eschar on the back of 1/20 Group 1 and 1/20 Group 4 animals; ano-genital staining in 1/20 Group 2 animals;
slight dehydration in 1/20 Group 3 animals, and a broken upper incisor in 1/20
Group 4 animals.
Corresponding detailed clinical observations included: hair loss in 2/20 Group 1,
2/20 Group 2, and 1/20 Group 3 animals; and urine stained/wet coat in 1/20
Group 2 animals.
Dermal irritation (if dermal study):
not specified
Mortality:
no mortality observed
Description (incidence):
All animals survived until scheduled sacrifice on GD20.
Body weight and weight changes:
effects observed, non-treatment-related
Description (incidence and severity):
Maternal Examinations During Pregnancy:Lower mean body weights were observed in Group 4 animals that were
statistically significant on Days 8-17 (p<0.05-0.001). Lower mean daily body
weight gain was also observed in the Group 4 animals on Days 5-8 (p<0.001) and
the overall Day 3-20 (p<0.05).
Mean body weights for animals in Groups 2 and 3 were generally comparable to
the control Group 1 throughout the study. Incidental statistically significant
decreases in mean body weights occurred in Group 3 on Day 8 (p<0.05).
Mean daily body weight gain for animals in Groups 2 and 3 were generally
comparable to control Group 1 throughout the study. Statistically significant
decrease in mean daily body weight gain occurred in Group 3 on Days 5-8
(p<0.001). Statistically significant increases in mean daily body weight gain
occurred in Group 3 on Days 8-11 (p<0.01) and in Group 4 on Days 11-14
(p<0.01). These incidental changes did not impact the overall body weight
parameters.
Animals in Group 1 had a mean final terminal body weight of 381.4g with a
mean final adjusted body weight of 300.924g following correction for gravid
uterine weight. The net adjusted weight change from GD3 to terminal sacrifice
was 66.874g. For Groups 2, 3 and 4, mean final body weights of 379.9, 380.2
and 360.5g were observed with mean final adjusted body weights of 304.042,
299.451 and 288.955g, respectively. The net adjusted weight change from GD3
to terminal sacrifice was 70.515g for Group 2, 65.751g for Group 3, and 55.105g
for Group 4. All gravid uterus and mean adjusted body weights for animals in
Groups 2-3 were comparable to control Group 1. Group 4 animals had a
statistically significant decrease in mean final adjusted body weights (p<0.05)
that correlated to a lower terminal body weight and was associated with a slightly
lower gravid uterine weight and lower adjusted weight change from GD3.
Food consumption and compound intake (if feeding study):
effects observed, non-treatment-related
Description (incidence and severity):
Lower mean daily food consumption and food efficiency were observed in Group
4 animals and were statistically significant for mean daily food consumption on
Days 5-11 (p<0.01-0.001) and mean food efficiency on Days 5-8 (p<0.001). A
statistically significant increase in mean food efficiency was observed on Days 8-
14 (p<0.01-0.001).
Mean daily food consumption for animals in Groups 2 and 3 were generally
comparable to control Group 1 throughout the study. Incidental statistically
significant decrease in mean food consumption occurred in Group 3 on Days 5-8
(p<0.01).
Food efficiency:
effects observed, non-treatment-related
Description (incidence and severity):
Mean food efficiency for animals in Groups 2 and 3 were generally comparable
to control Group 1 throughout the study. Statistically significant changes in
mean food efficiency occurred in Group 3 and consisted of decrease on Days 5-8
(p<0.01) and increase on Days 8-11 (p<0.001). These incidental changes did not
impact the overall body weight parameters.
Water consumption and compound intake (if drinking water study):
not specified
Ophthalmological findings:
not specified
Haematological findings:
not specified
Clinical biochemistry findings:
not specified
Urinalysis findings:
no effects observed
Behaviour (functional findings):
effects observed, non-treatment-related
Description (incidence and severity):
There were no gross abnormalities in any of the female rats at terminal sacrifice
on GD20.
Immunological findings:
not specified
Organ weight findings including organ / body weight ratios:
not specified
Gross pathological findings:
not specified
Neuropathological findings:
not specified
Histopathological findings: non-neoplastic:
not specified
Histopathological findings: neoplastic:
not specified
Other effects:
not specified
Details on results:
In summary, all animals survived until scheduled sacrifice on GD20, with one Group 2
female confirmed to be not pregnant and one Group 4 female found to have total litter
loss. Clinical signs attributed to the administration of Dibenzoyl methane were limited to
Group 4 females and consisted of increased incidence in alopecia and ano-genital
staining, ocular discharge, hypersalivation, and soft feces. These signs had
corresponding detailed clinical observations of hair loss, lacrimation, and increased or
excessive salivation. Generally, lower mean body weights, daily body weight gain, daily
food consumption, and food efficiency were observed in the Group 4 animals. Group 4
animals had a decrease in mean final adjusted body weights that correlated to a lower
terminal body weight and was associated with a slightly lower gravid uterine weight and
lower adjusted weight change from GD3. Due the nature and incidence of clinical
observations and the magnitude of body weight parameters decreases, these test
substance-related changes were not considered to be adverse.

Maternal developmental toxicity

Number of abortions:
no effects observed
Description (incidence and severity):
There were no abortions or premature deliveries throughout gestation of the
pregnant females. One Group 4 female (Animal 8077) was determined to have
suffered total litter loss
Pre- and post-implantation loss:
no effects observed
Description (incidence and severity):
Pre-implantation loss for all confirmed pregnant females in Groups 2-3 was
comparable to control Group 1 with mean values of 5.09, 2.96, and 5.91 for
Groups 1-3, respectively. A slight increase in pre-implantation loss at 9.56% was
observed for Group 4 females when compared to control Group 1. This increase
was observed to be within published data range and is therefore interpreted to be
of no toxicological significance (Hood, 2012).
Total litter losses by resorption:
no effects observed
Description (incidence and severity):
Total number of resorptions for all confirmed pregnant females in Group 2 and 3
were comparable to control Group 1 with mean values of 0.6, 0.5, and 0.6% for Groups 1-3, respectively. Group 4 confirmed pregnant females had a slightly
higher total number of resorptions of 1.3%, mainly due to the total litter loss.
These values resulted in post-implantation loss of 4.46, 4.17, 4.10, and 9.75% for
Groups 1-4, respectively. Although the increase in post-implantation loss was
observed to be within published data range (Hood, 2012), its correlation with the
presence of a total litter loss are interpreted to be of toxicological relevance but
no adversity.
Early or late resorptions:
effects observed, non-treatment-related
Description (incidence and severity):
Mean early resorptions were 0.4 for Groups 1-3 and 0.6 for Group 4. These values resulted in post-implantation loss of 3.07, 2.86, 2.71, and 4.33% for Group 1-4, respectively. No late resorptions were observed.
Dead fetuses:
no effects observed
Description (incidence and severity):
The number of live fetuses was comparable for all confirmed pregnant females.
The mean values of live fetuses per litter in Group 1 were 12.6 with a total of 20
litters. Group 2 with 19 viable litters, Groups 3 with 20 viable litters, and Group
4 with 19 (of 20) viable litters had an average number of live fetuses of 12.8,
12.6, and 11.5, respectively.
Changes in pregnancy duration:
not specified
Changes in number of pregnant:
not specified
Other effects:
not specified
Details on maternal toxic effects:
In summary, 20 females in Group 1 (100%), 19 females in Group 2 (95%), 20 females in
Group 3 (100%), and 20 females in Group 4 (100%) were confirmed pregnant. Under the
study conditions, administration of Dibenzoyl methane resulted in no adverse changes in
uterine parameters throughout the treatment period, for all confirmed pregnant females in
Group 2 and 3. Group 4 had one pregnant female with total litter loss and a slight
increase in post-implantation loss and number of resorptions that were not considered to
be adverse.

Effect levels (maternal animals)

Remarks on result:
other: not specified
Remarks:
not specified

Maternal abnormalities

Abnormalities:
not specified

Results (fetuses)

Fetal body weight changes:
effects observed, non-treatment-related
Description (incidence and severity):
Total mean litter weight was comparable between control and test substancetreated
animals. Values were 51.15, 52.38, 51.85, and 48.87 g in Groups 1-4,
respectively
Reduction in number of live offspring:
effects observed, non-treatment-related
Description (incidence and severity):
A total of 20 litters in Group 1 (251 fetuses), 19 litters in Group 2 (244 fetuses),
20 litters in Group 3 (252 fetuses), and 19 litters in Group 4 (229 fetuses) were
examined at caesarean section for external fetal malformations on GD20.
Changes in sex ratio:
effects observed, non-treatment-related
Description (incidence and severity):
The (external) fetal male sex ratio was 47.01, 52.46, 49.21 and 50.66% for
Groups 1-4, respectively, and was comparable across treatment groups.
Changes in litter size and weights:
effects observed, non-treatment-related
Description (incidence and severity):
Total mean litter weight was comparable between control and test substancetreated
animals. Values were 51.15, 52.38, 51.85, and 48.87 g in Groups 1-4,
respectively.
Changes in postnatal survival:
not specified
External malformations:
effects observed, non-treatment-related
Description (incidence and severity):
Malposition of the 4th sternebrae was observed in one Group 3 fetus (11F of
Dam 8054). Additional malformations occurred in one Group 1 fetus (5F of
Dam 8008) that consisted of absences of the 1st-6th lumbar vertebral arch, 2nd-13th
thoracic vertebral arch, and 2nd-13th thoracic ribs. These findings are considered
to be incidental and of no significance from a developmental toxicology
perspective.
Skeletal malformations:
effects observed, non-treatment-related
Description (incidence and severity):
One hundred and thirty-one (131) fetuses from 20 litters in Group 1, 126 from 19
litters in Group 2, 132 from 20 litters in Group 3, and 119 fetuses from 19 litters
in Group 4 were evaluated for skeletal malformations and developmental
variations
Visceral malformations:
no effects observed
Description (incidence and severity):
Of the 120 fetuses from 20 litters in Group 1, 118 from 19 litters in Group 2, 120
from 20 litters in Group 3, and 110 fetuses from 19 litters in Group 4 evaluated
for visceral malformations and developmental variations, no malformations were
noted in any fetus during visceral examination. One incidental developmental
variation of the ureters, a slight dilation on the right side, occurred in one Group
2 fetus (F7 of Dam 8036).
Other effects:
not specified
Details on embryotoxic / teratogenic effects:
Variations occurred with equal incidence in all groups on test consisting in most
cases of bone unossification or incomplete ossification. Overall, there was no
pattern of ossification changes associated with test substance administration and
therefore all ossification developmental variations are considered incidental or to
be within the developmental biological spectrum.
Fetuses evaluated in Groups 1-4, respectively, exhibited the following skeletal
variations in the caudal vertebrae: 22.1, 4.0, 4.5, and 6.7% incomplete
ossification of the 1st caudal vertebrae; 24.4, 24.6, 25.0, 31.9% unossified 2nd
caudal vertebrae; 51.9, 40.5, 34.1, and 36.1% incomplete ossification of the 2nd
caudal vertebrae; 99.2, 88.9, 94.7, and 95.0% unossified 3rd caudal vertebrae; 0.8,
10.3, 5.3, and 2.5% incomplete ossification of the 3rd caudal vertebrae; and 100.0,
99.2, 100.0 and 100.0% unossified 4th caudal vertebrae. Additional incidental
variation of unossified 1st caudal vertebrae was observed in two Group 1 fetuses.
Incomplete ossification of the 1st thoracic vertebral arch was observed in one
Group 1 fetus.
Incidental skeletal variations in the pelvic girdle included: bilateral unossified
ischium in one Group 1 fetus; bilateral incomplete ossification of the ischium in
one Group 1 fetus; bilateral incomplete ossification of the pubis in three Group 1
fetuses; and unilateral (right) incomplete ossification of the pubis in one Group 1
fetus.
Fetuses evaluated in Groups 1-4, respectively, exhibited the following variations
in the metatarsal bones: 99.2, 100.0, 100.0, and 98.3% unossified 1st phalanges
(bilateral); 99.2, 100.0, 100.0, and 99.2% unossified 2nd-5th phalanges (bilateral);
and 98.5, 100.0, 100.0, and 99.2% unossified 1st metatarsal (bilateral).
Additional incidental variations of incomplete ossification of the 1st metatarsal
(bilateral) in one Group 1 fetus and incomplete ossification of the 5th metatarsal
(bilateral) in one Group 3 fetus were observed.
Fetuses evaluated in Groups 1-4, respectively, exhibited the following variations
in the skull bones: 0.8, 0.8, 0.8 and 0.8% incomplete ossification of the occipital
bone; 2.3, 0.8, 1.5, and 0.8% unossified hyoid; and 12.2, 2.4, 2.3, and 1.7%
incomplete ossification of the hyoid. In addition, one Group 3 (0.8%) and two
Group 4 (1.7%) fetuses had incomplete ossification of the frontals (bilateral); one
Group 1 (0.8%), one Group 3 (0.8%), and three Group 4 (2.5%) fetuses had incomplete ossification of the parietals (bilateral); one Group 1 (0.8%), three
Group 3 (2.3%) and four Group 4 (3.4%) fetuses had incomplete ossification of
the interperietal; and one Group 2 (0.8%) fetus had incomplete ossification of the
left maxilla.
Incidental skeletal variations in the ribs included: short 13th thoracic rib on the
left side of two Group 2 fetuses and one Group 4 fetus; short 13th thoracic rib on
the right side of one Group 2 and one Group 4 fetus; and supernumerary 14th
thoracic rib (bilateral) in two Group 1 fetuses, two Group 2 fetuses, and one
Group 3 fetus, supernumerary 14th thoracic rib on the left side of four Group 1
fetuses and one Group 4 fetus; and supernumerary 14th thoracic rib on the right
side of one Group 1 fetus.
Fetuses evaluated in Groups 1-4, respectively, exhibited the following variations
in the sternebra: 3.1, 6.3, 6.1, and 21.0% incomplete ossification of the 2nd
sternebra; 3.1, 3.2, 5.3, and 16.8% incomplete ossification of the 4th sternebra;
6.9, 10.3, 16.7, and 25.2% unossified 5th sternebra; 80.9, 82.5, 71.2, and 68.1%
incomplete ossification of the 5th sternebra; 2.3, 1.6, 1.5, and 1.7% unossified 6th
sternebra; and 60.3, 44.4, 40.9, and 53.8% incomplete ossification of the 6th
sternebra. In addition, one Group 1 fetus had unossified 1st-3rd sternebra; one
Group 4 fetus had bipartite ossification of the 1st-3rd and 6th sternebra; one Group
1 fetus and three Group 3 fetuses had incomplete ossification of the 1st sternebra;
two Group 1, three Group 3; and two Group 4 fetuses had incomplete ossification
of the 3rd sternebra; one Group 1 and one Group 3 fetus had unossified 4th
sternebra; one Group 3 and one Group 4 fetus had bipartite ossification of the 4th
sternebra; and one Group 1, one Group 3, and three Group 4 fetuses had bipartite
ossification of the 5th sternebra.
Incidental skeletal variations in the cervical vertebrae included incomplete
ossification of 3rd-5th cervical vertebral arch in one Group 4 fetus and of the 6th
cervical vertebral arch in one Group 2 and one Group 4 fetus.
In the pectoral girdle, 25.2, 11.1, 7.6, and 12.6% of fetuses in Groups 1-4,
respectively, exhibited an unossified 4th metacarpal (bilateral) and 13.0, 9.5, 15.9,
10.9% had incomplete ossification of the 4th metacarpal (bilateral). Bilateral
unossification of the 1st (98.5, 100.0, 99.2, and 97.5%), 2nd (79.4, 64.3, 50.8, and
55.5%), 3rd (85.5, 75.4, 62.1, and 63.9%), 4th (99.2, 100.0, 99.2, and 99.2%), and
5th (99.2, 100.0, 99.2, and 98.3%) phalanges occurred in Groups 1-4,
respectively. Additional incidental variations in the pectoral griddle included:
incomplete ossification of the 4th metatarsal (left) in three Group 1, three Group 2
and one Group 3 fetuses; unossified 1st-5th phalange (left) in one Group 1 fetus;
and incomplete ossification of the 2nd phalange (bilateral) in one Group 1, two
Group 3, and two Group 4 fetuses.
Incidental skeletal variations in the sacral vertebra included: unossification of
the 1st-4th sacral vertebral arch in one Group 1 fetus; incomplete ossification of
the 3rd sacral vertebral arch in two Group 1 fetuses; and incomplete ossification
of the 4th sacral vertebral arch in twelve Group 1 fetuses, two Group 3 fetuses,
and one Group 4 fetus.
In summary, the (external) fetal male sex ratios, total mean litter weight, and number of
live fetuses per litter were comparable across treatment groups. Under the study conditions, the administration of Dibenzoyl methane resulted in no treatment-related
external, visceral or skeletal teratogenic effects.

Effect levels (fetuses)

Dose descriptor:
NOAEL
Effect level:
<= 400 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
external malformations
visceral malformations
Remarks on result:
other:

Fetal abnormalities

Abnormalities:
effects observed, non-treatment-related
Localisation:
other: abdomen/tail
Description (incidence and severity):
Aside from a incidental variation of the abdomen/tail area in Group 1, noted as a
“thread-like tail” for fetus number 5 (F5) of Dam 8008, no other external
abnormalities were observed in any pups in Groups 1-4.

Overall developmental toxicity

Key result
Developmental effects observed:
yes
Lowest effective dose / conc.:
400 mg/kg bw/day (nominal)
Treatment related:
yes
Relation to maternal toxicity:
not specified
Dose response relationship:
yes
Relevant for humans:
not specified

Applicant's summary and conclusion

Conclusions:
Under the conditions of the study and based on the maternal and fetal developmental toxicity
endpoints evaluated, the no-adverse-effect level (NOAEL) for general toxicological and
developmental parameters for the administration of Dibenzoyl methane by oral gavage was
determined to be 400 mg/kg/day.
Executive summary:

A prenatal developmental toxicity study was conducted in timed-pregnant CRL Sprague-Dawley

CD® IGS rats to determine the potential of Dibenzoyl methane to produce pre-natal

developmental toxicity, when administered orally throughout pregnancy, from implantation to

one day prior to term delivery. Eighty (80) timed-pregnant female rats were selected for the test

and equally distributed into four groups (twenty females per group). Dose levels of 100, 250, and

400 mg/kg/day of Dibenzoyl methane, respectively, as well as vehicle control (corn oil), were

selected for the test.

The test substance or vehicle control (corn oil) was administered daily (7 days/week) via oral

intubation to each rat during gestation days (GD) 5-19 of a 21-day pregnancy. The test substance

was administered as a 25 mg/mL, 62.5 mg/mL, 100 mg/mL w/v mixture in corn oil. Animals

were observed daily during pregnancy for clinical signs and mortality. Individual body weights

and food consumption for all pregnant females are reported on GD3, 5, 8, 11, 14, 17, and 20.

Gross necropsies and caesarean sections were performed on all pregnant rats, where the

pregnancy status and uterine contents were evaluated. The conceptuses were assessed for

viability, external observations, and then for visceral and skeletal variations.

The neat test substance, as determined by measured Dibenzoyl methane, was found to be stable

under the conditions of storage at PSL over the course of this study. The test substance was

considered to be homogenously distributed in all dose solutions. All concentration verification

values were slightly above the targeted concentrations, indicating the animals received at least the

dose levels of 100, 250, and 400 mg/kg/day for Groups 2-4, respectively.

All animals survived until scheduled sacrifice on GD20, with one Group 2 female confirmed to

be not pregnant and one Group 4 female found to have total litter loss. Clinical signs attributed to

the administration of Dibenzoyl methane were limited to Group 4 females and consisted of

increased incidence in alopecia, ano-genital staining, ocular discharge, hypersalivation and soft

feces. These signs had corresponding detailed clinical observations of hair loss, lacrimation, and

increased or excessive salivation. Generally, lower mean body weights, daily body weight gain,

food consumption, and food efficiency were observed in the Group 4 animals. Group 4 animals

had a decrease in mean final adjusted body weights that correlated to a lower terminal body

weight and was associated with a slightly lower gravid uterine weight and lower adjusted weight

change from GD3. Due the nature and incidence of clinical observations and the magnitude of

body weight parameters decreases, these test substance-related changes were not considered to be

adverse.

Administration of Dibenzoyl methane resulted in no adverse changes in uterine parameters

throughout the treatment period, for all confirmed pregnant females carrying viable fetuses to

GD20 in Group 2 and 3. Group 4 had one pregnant female with total litter loss and a slight

increase in post implantation loss and number of resorptions that were within published data

range and therefore not considered to be adverse.

A total of 20 litters in Group 1 (251 fetuses), 19 litters in Group 2 (244 fetuses), 20 litters in

Group 3 (252 fetuses), and 19 litters in Group 4 (229 fetuses) were examined at caesarean section

for external fetal malformations on GD20, prior to evaluation for visceral or skeletal

malformations and developmental variations. The (external) fetal male sex ratio, total mean litter

weight, and the number of live fetuses were comparable across treatment groups. There were no

external, visceral or skeletal teratogenic effects related to the administration of Dibenzoyl

methane.

Under the conditions of the study, and based on the maternal and fetal developmental toxicity

endpoints evaluated, the no-adverse-effect level (NOAEL) for general toxicological and

developmental parameters for the administration of Dibenzoyl methane by oral gavage was

determined to be 400 mg/kg/day.