Registration Dossier

Administrative data

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Referenceopen allclose all

Endpoint:
screening for reproductive / developmental toxicity
Remarks:
based on test type (migrated information)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
27 August to 22 October 2013
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: compliance to GLP and testing guideline, coherence between data, results and conclusions
Qualifier:
according to
Guideline:
OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)
Version / remarks:
adopted on 22 March 1996
Deviations:
no
GLP compliance:
yes
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
A total of 90 Sprague Dawley [Crl:CD(SD)BR] rats (45 males and 45 virgin females), 6 to 7 weeks old and weighing 190 - 217 g for males and 175 - 189 g for females, were received from Charles River Italia S.p.A., Italy.
After arrival the weight range for each sex was determined and the animals were temporarily identified within the cage by means of a coloured mark on the tail. A health check was then performed by a veterinarian.
An acclimatisation period of 13 days was allowed before the start of treatment, during which time the health status of the animals was assessed by thorough observations.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C +/- 2°C
- Humidity (%): 55% +/- 15%
- Air changes (per hr): 15 to 20 air changes per hour
- Photoperiod (hrs dark / hrs light): artificial light for 12 hours each day
No relevant deviations from these ranges were recorded during the study.

In-life phase: August 2013 to 22 October 2013
Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
The test item was administered orally by gavage at a dose volume of 5 mL/kg body weight. Control animals received the vehicle alone at the
same dose volume.

The required amount of Butyl diglycol methacrylate was suspended in the vehicle (corn oil) and brought to the final volume appropriate for each
concentration (concentrations of 20, 60 and 200 mg/mL) and kept under magnetic stirrer at room temperature prior to use and until the time of dosing of the last animal.
The formulations were prepared daily and the concentrations were calculated and expressed in terms of test item as supplied.
Details on mating procedure:
Mating was monogamous (one male to one female). A vaginal smear was taken from the day after the start of pairing until positive identification of
copulation (sperm identification, vaginal plug in situ or copulation plugs found in the cage tray).
The female was paired with the same male until positive identification occurred or 14 days had elapsed.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Prior to commencement of treatment, analysis was performed to confirm that the proposed formulation procedure was acceptable (concentration
and homogeneity). Results of the analyses were within the limits of acceptance.
The stability was found to be 24 hours at room temperature in the concentration range of 20 to 200 mg/mL.
Samples of the formulations prepared on Week 1 and last Week were also analysed to check the concentration and homogeneity. Results of the analyses were within the limits of acceptance.
Chemical analysis was carried out by the Analytical Chemistry Department at RTC according to a validated method (RTC Study No. 96370), in the range from 5 to 200 mg/mL.
Duration of treatment / exposure:
Males
Animals were dosed once a day, 7 days a week, for a minimum of 2 consecutive weeks prior to pairing and thereafter through the day before necropsy
(Day 29 - 30 of treatment).

Dose volumes were adjusted once per week for each animal according to the last recorded body weight.

Females
Animals were dosed once a day, 7 days a week, for a minimum of 2 consecutive weeks prior to pairing and thereafter during pairing, post coitum and
post partum periods until Day 3 post partum (the day before sacrifice).

Dose volumes were adjusted once per week for each animal according to the last recorded body weight.
During the gestation period, dose volumes were calculated according to individual body weight on Days 0, 7, 14 and 20 post coitum and on Day 1
post partum. Thereafter individual dose volumes remained constant.
Frequency of treatment:
once daily
Remarks:
Doses / Concentrations:
100, 300 and 1000 mg/kg/day
Basis:
nominal conc.
No. of animals per sex per dose:
The test item was administered orally, by gavage. The oral route was selected as it is a possible route of exposure of the test item in man.
3 groups comprised 10 males and 10 females rats received the test item at the dose levels of 100, 300 and 1000 mg/kg/day.
Each group comprised 10 male and 10 female rats.
Control animals:
yes
Details on study design:
Dose levels of 100, 300 and 1000 mg/kg/day were selected by the Sponsor based on information from a previous non GLP compliant study (2 week preliminary study) (RTC Study no.: 96020EXT).
Parental animals: Observations and examinations:
Mortality

Throughout the study, all animals were checked early in each working day in the morning and in the afternoon. At weekends and Public Holidays a
similar procedure was followed except that the final check was carried out at approximately mid-day.

Clinical signs

Once before commencement of treatment and at least once daily during the study, each animal was observed and any clinical signs were recorded.
Observations were performed at the same time interval each day, the interval was selected taking into consideration the presence of post-dose reactions.

Clinical observations (Functional Observation Battery Tests)

Once before commencement of treatment and once a week thereafter, each animal was given a detailed clinical examination.
Each animal was removed from the home cage and observed in an open arena.
The tests included observation of changes in gait and posture, reactivity to handling, presence of clonic or tonic movements, stereotypies or bizarre
behaviour and effects on the autonomic nervous system (e.g. lachrymation, piloerection, pupil size, unusual respiratory pattern).
All observations were recorded for individual animals.

All observed parameters are reported in a group incidence table.

Grip strength and sensory reactivity to stimuli

Once during the study, towards the end of treatment, 5 males and 5 females were randomly selected from each group for evaluation of sensory reactivity to stimuli of different modalities (e.g. auditory, visual and proprioceptive stimuli); an assessment of grip strength was also performed. Measurements were performed using a computer generated random order. For males the tests were performed on day before necropsy of the study and for females on Day 3 post partum.

Motor activity assessment (MA)

Once during the study, towards the end of treatment, 5 males and 5 females were randomly selected from each group and the motor activity was measured (for approximately 5 minutes) by an automated activity recording device. Measurements were performed using a computer generated random order. For males the tests were performed the day before necropsy and for females on Day 3 post partum.

Body weight

Males were weighed weekly from allocation to termination.

Females were weighed weekly from allocation to positive identification of mating and on Days 0, 7, 14 and 20 post coitum. Dams were also weighed on Days 1 and 4 post partum.

Food consumption

The weight of food consumed by each cage of males and females was recorded weekly during the pre-mating period starting from allocation.
Individual food consumption for the females was measured on gestation Days 7, 14 and 20 post coitum starting from Day 0 post coitum and on Day 4 post partum starting from Day 1 post partum.



Oestrous cyclicity (parental animals):
Vaginal smears were taken daily in the morning starting two weeks before pairing until a positive identification of copulation was made.
The vaginal smear data were examined to determine the following:

a) anomalies of the oestrous cycle;
b) pre-coital interval (i.e., the number of nights paired prior to the detection of mating).
Sperm parameters (parental animals):
Parameters examined in [all/P/F1/F2] male parental generations:
Testis weight, epididymis weight. The testes and epididymides were cut at 2-3 micrometer thickness and stained with Periodic Acid Schiff (PAS).
The morphological evaluation of the seminiferous epithelium (staging of spermatogenic cycle) was performed.
Litter observations:
A parturition check was performed from Day 20 to Day 25 post coitum. Females which did not give birth after 25 days of post coitum period were sacrificed shortly after. Gestation length was calculated as the time between the day of successful mating (Day 0 post coitum) and the day of commencement of birth (i.e. first detected presence of offspring in the cage). The day that offspring were first detected in the cage was considered Day 0 post partum.

As soon as possible, after parturition was considered complete (Days 0 or 1 post partum), all pups (live and dead) were counted, sexed and live pups were identified. Live pups were individually weighed on Days 1 and 4 post partum.
Pups killed or dying during the lactation period were weighed before the despatch to necropsy.
Observation was performed once daily for all litters.
Postmortem examinations (parental animals):
Parental animals were killed by exsanguination under isofluorane anaesthesia.
Pups were euthanised by intraperitoneal injection of Thiopenthal

Parental males:
The males were killed after the mating of all females (after 29-30 days of treatment).

Parental females:
The females with live pups were killed on Day 4 post partum.
The females which did not give birth 25 days after positive identification of mating were killed shortly after.

Necropsy

The clinical history of the males and females of the parental generation was studied and a detailed post mortem examination was conducted
(including examination of the external surface and orifices). Changes were noted, the requisite organs weighed and the required tissue samples
preserved in fixative and processed for histopathological examination.

Females:
All females were examined also for the following:

- number of visible implantation sites (pregnant animals);
- number of corpora lutea (pregnant animals).

Uteri of female with no visible implantations were immersed in a 10-20% solution of ammonium sulphide to reveal evidence of implantation.


Organ weights

From all animals completing the scheduled test period, the organs were dissected free of fat and weighed.
The ratios of organ weight to body weight were calculated for each animal.

Tissues fixed and preserved

Samples of all the tissues listed were fixed and preserved in 10% neutral buffered formalin (except eyes, optic nerves and Harderian glands, testes and epididymides which were fixed in modified Davidson's fluid and preserved in 70% ethyl alcohol).

Histopathological examination

The tissues required for histopathological examination are listed in Annex 1. After dehydration and embedding in paraffin wax, sections of the
tissues were cut at 5 micrometer thickness and stained with haematoxylin and eosin.
In addition, the testes and epididymides were cut at 2-3 micrometer thickness and stained with Periodic Acid Schiff (PAS). The morphological
evaluation of the seminiferous epithelium (staging of spermatogenic cycle) was performed.

The examination was restricted as detailed below:

a) Tissues specified in Annex 1 from 5 males and 5 females randomly selected (animals evaluated for clinical pathology) in the control and
high dose groups killed at term.
b) All abnormalities in all groups.
Postmortem examinations (offspring):
Pups
All pups found dead in the cage were examined for external and internal abnormalities.
All live pups sacrificed at termination were examined for external abnormalities and sex confirmation by gonadal inspection. All pups with
abnormalities were retained in an appropriate fixative.
Statistics:
Standard deviations were calculated as appropriate. For continuous variables the significance of the differences amongst group means was assessed by Dunnett’s test or a modified t test, depending on the homogeneity of data.
Statistical analysis of histopathological findings was carried out by means of the non-parametric Kolmogorov-Smirnov test if n was more than 5. The
non-parametric Kruskal-Wallis analysis of variance was used for the other parameters. Intergroup differences between the control and treated
groups were assessed by the non-parametric version of the Williams test. The criterion for statistical significance was p<0.05. The mean values,
standard deviations and statistical analysis were calculated from actual values in the computer without rounding off.
Reproductive indices:
Group mean values were calculated for all parameters. Data from non-pregnant females were excluded from group mean calculations.

The following reproductive indices were calculated:

Males

Copulatory Index (%) = no. of animals mated/no. of animals paired x 100

Fertility Index (%) = no. of males which induced pregnancy/no. of animals paired x 100

Females

Copulatory Index (%) = no. of animals mated/no. of animals paired x 100

Fertility Index (%) = no. of pregnant females/no. of females paired x 100

Males and Females

Pre-coital Interval = Mean number of days between pairing and mating
Sex ratios were calculated at birth and on Day 4 post partum and were presented as the percentage of males per litter.




Offspring viability indices:
Females

Pre-birth loss was calculated as a percentage from the formula:

(No. of visible implantations-total litter size at birth)/No. of visible implantations x 100

Pup loss at birth was calculated as a percentage from the formula:

(Total litter size-live litter size)/Total litter size x 100

Cumulative pup loss on Day 4 post partum was calculated as a percentage from the formula:

(Total litter size at birth-live litter size at Day 4 post partum)/Total litter size at birth x 100

Pre- implantation loss was calculated as a percentage from the formula:

(no. of corpora lutea - no. of implantations)/no. of corpora lutea x 100
Clinical signs:
no effects observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Other effects:
no effects observed
Reproductive function: oestrous cycle:
no effects observed
Reproductive function: sperm measures:
no effects observed
Reproductive performance:
no effects observed
Mortality

No mortality occurred throughout the study. A total of 3 females were found not pregnant at necropsy: 2 in the mid-dose group and 1 in the high
dose group. The number of females with live pups on Day 4 post partum was: 10 each in the control and low dose groups (0 and 100 mg/kg bw/day), 8 in the mid-dose group (300 mg/kg bw/day) and 9 in the high dose group (1000 mg/kg bw/day).

Clinical signs and clinical observations (Functional Observation Battery Tests)

No relevant clinical signs were observed throughout the study in all treated animals of both sexes.
Observation of animals at removal from the cage and in an open arena (neurotoxicity assessment) did not reveal changes attributable to the test
item.

Motor activity and sensory reaction to stimuli

No relevant differences were noted in all parameters investigated between control and treated groups

Body weight and body weight gain
Means of body weight and body weight gain were comparable between control and treated groups both in males and females throughout the study.
The statistically significant decrease in body weight and/or body weight gain, detected in low dose group of males before pairing and during
mating, as well as the statistically significant increase in body weight gain of low dose group of females before pairing were considered of no
toxicological relevance since the changes were minimal and not dose-related.
In addition, decreases in body weight and body weight gain, noted during the post partum phase in control and treated females, were considered as a normal consequence of the parturition occurred in the females.

Food consumption

Food consumption was unaffected by treatment in both sexes during the study. The statistically decrease detected in the high dose group on Day 7
post coitum was minimal and not considered related to treatment.

Haematology

Reticulocytes were decreased in animals dosed with 1000 mg/kg/day (approximately 33%). Due to the absence of changes in the red cells
parameters, the above reticulopenia was considered toxicologically irrelevant. In addition, the statistically significant decrease of mean
corpuscular haemoglobin concentration, recorded in males dosed with 100 mg/kg/day and 1000 mg/kg/day (2%), was considered of no
toxicological importance due to its minimal severity. No changes were recorded in coagulation parameters.

Clinical chemistry

Statistically significant increase of glucose (50%) and potassium (14%) and decrease of cholesterol (27%), protein (9%), albumin (11%), calcium (3%)
and sodium (1%) were recorded in males dosed with 1000 mg/kg/day. No changes were recorded in treated females. Due to the slight severity of
the above changes, the recorded findings were not considered adverse.


Oestrus cycle, reproductive parameters, pairing combination and mating performance

Oestrous cycle and reproductive parameters (pre-coital intervals, copulatory and fertility indices) did not show relevant differences between treated and control groups.

Implantation, pre-birth loss data and gestation length of females

Corpora lutea, implantations, pre-implantation loss and total litter size were similar between treated and control groups. The slight increase in
pre-birth loss percentage detected in mid- and high dose groups when compared to controls was not statistically significant and not dose-related. Gestation periods were similar in treated groups and controls.

Terminal body weight and organ weights

Terminal body weight was unaffected by treatment in both sexes. Some statistically significant differences were noted in the absolute and/or
relative organ weight of treated animals when compared to controls, such as:
– Higher absolute heart weight in low dose females (+11%).
– Lower absolute spleen weight in high dose females (-19%).
– Higher absolute and relative thymus weight in mid-dose females (+35% and +37% respectively).
– Higher relative kidneys weight in low dose males (+ 9%) and high dose females (13%).
All the above differences were of low magnitude and occurred without dosedependency. Therefore, they were considered unrelated to treatment.

Macroscopic observations
Detailed macroscopic observations have been reported for male and female animals from all groups. No remarkable changes were noted at post
mortem examination in treated animals when compared to controls.

Microscopic observations

Histopathological evaluation was performed on five randomly selected control and high dose males and females, as well as on all abnormalities
detected during post mortem observation. In addition, a detailed qualitative examination of the testes was performed in five randomly selected
control and high dose group males. No treatment-related findings were observed in high dose males and females. Seminiferous tubules were
evaluated with respect to their stage in the spermatogenic cycle and to the integrity of the various cell types within the different stages; regular
layering in the germinal epithelium was noted. The lesions reported in control and treated animals were considered to be an expression of
spontaneous and/or incidental pathology, commonly seen in this species and age under our experimental conditions.
Key result
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: general toxicity
Key result
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: fertility
Clinical signs:
no effects observed
Mortality / viability:
no mortality observed
Body weight and weight changes:
no effects observed
Gross pathological findings:
no effects observed
Litter data at birth, on Day 1 and on Day 4 post partum of females and sex ratio of pups

No differences in total and live litter size, litter weight, mean pup weight and sex ratio were noted between groups at birth and on Day 4 post partum.

Clinical signs of pups

Apparently no food intake (milk), small appearance and pallor were the clinical signs noted in pups of the control and treated groups. A
malformation (acaudia) was detected in one foetus (female no. 96380039) of the low dose group. These clinical signs noted in pups were
considered unrelated to treatment.

Necropsy findings in decedent pups and in pups sacrificed on Day 4 post partum

Necropsy findings in decedent pups and in pups sacrificed on Day 4 post partum did not reveal any treatment-related effect.
Key result
Dose descriptor:
NOAEL
Generation:
F1
Effect level:
1 000 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: no effects observed
Reproductive effects observed:
not specified

Oestrus cycle – Before pairing - Group summary data

 -----------------------------------------------------------------------------------------------------------------------------------

           Group 1                     Group 2                    Group 3                     Group 4

 Animal    Oestrus           Animal    Oestrus          Animal   Oestrus          Animal   Oestrus

 Number   Cycles            Number    Cycles           Number   Cycles         Number   Cycles

 -----------------------------------------------------------------------------------------------------------------------------------

96380001       2       96380021       1       96380041       3       96380061       3

96380003      4       96380023       2       96380043       3       96380063       3

96380005      2        96380025      2       96380045       2       96380065       3

96380007      4       96380027       0       96380047       2       96380067       2

96380009      2       96380029       3       96380049       2       96380069       2

96380011      3        96380031      3       96380051       2       96380071       2

96380013      2       96380033       3       96380053       2       96380073       2

96380015      3       96380035       2       96380055       4       96380075       2

96380017      2       96380037       4       96380057       3       96380077       4

96380019     1       96380039        2       96380059       1       96380079       2

    Means         2.5                                 2.2                            2.4                               2.5

 -----------------------------------------------------------------------------------------------------------------------------------

 Note: The number of oestrus cycles is based on the number of non sequential days the dams were in oestrus.

Reproductive parameters of males - Summary

 -----------------------------------------------------------------------------------------------------------------------------------

                              Group         1                 2                3                 4

 -----------------------------------------------------------------------------------------------------------------------------------

 

   Copulatory Index%             100.0            100.0            100.0         100.0

 

 -----------------------------------------------------------------------------------------------------------------------------------

 

   Fertility Index%                  100.0            100.0             80.0          90.0

 

 -----------------------------------------------------------------------------------------------------------------------------------

Reproductive parameters of females – Summary

 -----------------------------------------------------------------------------------------------------------------------------------

                              Group              1                 2                3                 4

 -----------------------------------------------------------------------------------------------------------------------------------

 

   Copulatory Index%                    100.0            100.0          100.0         100.0

 

 -----------------------------------------------------------------------------------------------------------------------------------

 

   Fertility Index%                        100.0            100.0           80.0          90.0

 

 -----------------------------------------------------------------------------------------------------------------------------------

Conclusions:
On the basis of the results obtained in this study with Butyl diglycol methacrylate, the NOAEL (No Observed Adverse Effect Level) the NOAEL for
reproductive toxicity was found to be 1000 mg/kg/day for males and females.
Executive summary:

In a Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test according to OECD Guideline 422 (22 March 1996) Butyl diglycol methacrylate was administered to 10 Hsd: Sprague Dawley SD rats/sex/dose orally by gavage at dose levels of 0 (control), 100, 300 and 1000 mg/kg bw/d. The treatment schedule included 2 weeks before pairing for males and during pairing with females until the day before necropsy, for a total of 29/30 days. Females were treated for 2 weeks prior to pairing, during pairing and throughout the gestation and lactation periods until Day 3 post partum. The following investigations were performed in all groups: body weight, clinical signs (including neurotoxicity assessment, motor activity and sensory reaction to stimuli), food consumption, oestrous cycle, mating performance, clinical

pathology investigations (haematology and clinical chemistry), litter data, macroscopic observations, organ weights and histopathological examination. Clinical signs and macroscopic observations of pups were also performed. The histopathological examination was performed only on control and high dose groups (five animals/sex/group selected randomly). It included identification of the stages of the spermatogenic cycle in five males.

No animals died during the study. A total of 3 females were found not pregnant at necropsy: 2 in the mid-dose group and 1 in the high dose group. The number of females with live pups on Day 4 post partum was: 10 each in the control ad low dose groups, 8 in the mid-dose and 9 in the high dose groups.

No relevant clinical signs were seen throughout the whole study in treated animals of both sexes.

Clinical observations for neurotoxicity assessment (removal of animals from the home cage and open arena) did not reveal changes attributable to the test item.

Motor activity and sensory reaction to stimuli revealed in no relevant differences in all parameters investigated between

control and treated groups of both sexes.

No differences of toxicological significance in body weight and body weight gain were recorded in animals of both sexes compared to the control group, throughout the study.

Food consumption was unaffected by treatment in both sexes during the study.

Haematology: No changes of toxicological relevance were seen.

Clinical chemistry: No adverse findings were detected at any dose.

All females mated both in the control and treated groups. Oestrous cycle, precoital intervals, copulatory index and fertility index did not show intergroup differences.

Corpora lutea, implantations, pre-implantation and pre-birth loss percentages, total litter size and gestation length did not reveal any treatment-related effect. No differences in total and live litter size, litter weight, mean pup weight and

sex ratio were noted between groups at birth and on Day 4 post partum.

Clinical signs noted in pups throughout the study were considered unrelated to treatment.

Necropsy findings in decedent pups and in pups sacrificed on Day 4 post partum did not reveal any treatment-related effect.

Terminal body weight was unaffected by treatment in both sexes. Changes in organ weights were of slight severity and therefore considered of no toxicological significance.

Macroscopic observations: No remarkable changes were noted at post mortem examination in treated animals when compared to controls.

Microscopic observations: No treatment-related findings were observed in high dose males and females.

Conclusions:

This study is acceptable and satisfies the guideline requirement for a Screening reproductive study according to OECD 422 in rats.

On the basis of the results obtained in this study, the NOAEL (No Observed Adverse Effect Level) for general toxicity was considered to be 1000 mg/kg/day for males and females.

The NOAEL for reproductive toxicity was also found to be 1000 mg/kg/day for males and females.

Endpoint:
fertility, other
Remarks:
based on test type (migrated information)
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Study period:
1993
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well documented and in accordance to scientifically accepted principles, minor deviations to OECD guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
90 days exposure of males and females pre-mating, mating, females were traeted through day day 20 of gestation and allowed to deliver and nurse their offspring through day 21 of lactation (weaning)
GLP compliance:
not specified
Limit test:
yes
Species:
rat
Strain:
other: CD
Sex:
male/female
Details on test animals and environmental conditions:
- Source: CharlesRiver Lab., Raleigh,NC (USA)
- Age at study initiation: 8 weeks

- Housing: individually in suspended stainless steel cages
- Diet: Certified Purina Rodent Chow ad libitum
- Water: from Elizabethtown Water Company, ad libitum):
- Acclimation period: 2 weeks
Route of administration:
dermal
Vehicle:
unchanged (no vehicle)
Details on exposure:
DETAILS ON EXPOSURE
- Area of exposure: back
- % coverage: 3 x 3 cm area
- Type of wrap if used: polyethylene patch, covered by an adhesive bandage wrapped around the trunk


REMOVAL OF TEST SUBSTANCE
- Washing (if done): residual test material was gently wiped from the application site
- Time after start of exposure: 6 hrs

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg/d
- Concentration: undiluted
- Constant volume or concentration used: yes
Details on mating procedure:
no
Analytical verification of doses or concentrations:
yes
Duration of treatment / exposure:
Males: 13 weeks pre-mating , then until mating was finished
Females: 13 weeks pre-mating and thereafter gestation period (20 days) and lactation period (21 days)
Frequency of treatment:
Males and females : 5 days/ week, 6 hrs/day pre-mating
Females: 7 days/week, 6 hrs/day during gestation and lactation period
Remarks:
Doses / Concentrations:
2000 mg/kg/d
Basis:
nominal conc.
No. of animals per sex per dose:
25
Control animals:
yes
other: distilled water
Positive control:
no
Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS: Yes

DETAILED CLINICAL OBSERVATIONS: Yes

BODY WEIGHT: Yes

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined : Yes

Oestrous cyclicity (parental animals):
Yes
Sperm parameters (parental animals):
Parameters examined in male parental generation:
[testis , epididymis , seminal vesicles, prostate gland
Litter observations:
STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- Maximum of 8 pups/litter (4/sex/litter as nearly as possible); excess pups were killed and discarded.

PARAMETERS EXAMINED
The following parameters were examined in offspring:
[number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain

Postmortem examinations (parental animals):
SACRIFICE
- Male animals: All surviving animals after mating was complete
- Maternal animals: All surviving animals after weaning

GROSS NECROPSY
Yes, all animals

HISTOPATHOLOGY / ORGAN WEIGHTS
Parental males: testes, epididymes, seminal vesicles, prostate glands
Postmortem examinations (offspring):
SACRIFICE
- The offspring animals were sacrificed at 21 days of age.
- These animals were subjected to postmortem examinations (macroscopic and/or microscopic examination) as follows:

GROSS NECROPSY
yes
Statistics:
Bartlett's test / ANOVA (parametric procedures)
Kruskal-Wallis test (non-parametric procedures)
Furtherly used: Dunn's summed-rank test; Jonckheere's test for monotonic trends for nonparametric comparisons; Fisher exact test.
Reproductive indices:
Mating index, males : dose group: 80 %, controls: 80 %
Mating index, females: dose group: 96 %, controls :96 %

Pregnancy rates: dose group: 79.2 %, controls: 83.3 %
Male fertility index: dose group: 80 %, controls: 81 %
Offspring viability indices:
Number of litters: dose group: 19; controls: 20
Mean gestation length (days): dose group .21.4; controls: 21.5

Mean number of pups at birth day (day 0):
dose group: live: 13.9; dead: 0.4; total: 14.3
controls: 14.2; dead: 0.4; total: 14.6


Pups survival indices

Day 0-4
dose group :97.0 %
controls: 95.4 %

Day 4-21
dose group: 100.0 %
controls: 96.3 %

Mean pup weights [g]
Day 0: dose group: 6.8; controls: 6.8
Day 4: dose group: 10.4; controls: 10.5
Day 14: dose group: 35.5; controls: 35.6
Day21: dose group: 53.8; controls: 53.4


Clinical signs:
no effects observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Other effects:
no effects observed
Reproductive function: oestrous cycle:
no effects observed
Reproductive function: sperm measures:
no effects observed
Reproductive performance:
no effects observed
Dose descriptor:
NOAEL
Effect level:
2 000 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Mortality / viability:
no mortality observed
Body weight and weight changes:
no effects observed
Gross pathological findings:
no effects observed
Dose descriptor:
NOAEL
Generation:
F1
Effect level:
2 000 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Reproductive effects observed:
not specified
Conclusions:
Butyldiglycol showed no effects on reproduction parameters in parental rats and offspring when administered dermally for 13 weeks
Executive summary:

The alcohol Butyldigylycol (CAS 112-34-5) was tested for toxicity to reproduction in a well conducted repeated dose study in rats (25 animals per sex and dose group). The substance was applied dermally at a dose of 2000 mg/kg to males for 90 days pre-mating and until mating was successful. Females were exposed 90 for days pre-mating and during the gestation (20 days) and lactation period (21 days). Parental animals showed no substance induced effects on fertility, reproductive indices did not differ from controls. Litters delivered were allowed to grow until the end of lactation. They showed no signs of teratogenicity or fetotoxicity and no deviation to controls in offspring viability indices. There was no evidence for systemic toxicity by clinical and histopathological evaluations for all animals. Therefore, the NOAEL of the study can be determined to 2000 mg/kg/d.

Effect on fertility: via oral route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
subacute
Species:
rat
Quality of whole database:
Neither the methacrylate moiety nor the higher glycol ethers and particularly butyldiglycol appear to affect fertility. Furthermore Butyldiglycol methacrylate showed no impact on fertility when tested in rats in an OECD 422 combined repeat dose and reproductive/developmental toxicity screening test (HRTF, 2014).
Effect on fertility: via inhalation route
Endpoint conclusion:
no study available
Effect on fertility: via dermal route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
2 000 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
Publication; well documented and in accordance to scientifically accepted principles
Additional information

Butyldiglycol methacrylate (BDGMA) was studied in an OECD 422 combined repeat dose and reproductive/developmental toxicity screening test (HRTF, 2014). Groups of 10 male and 10 female rats were administered by gavage at dose levels of 0, 100, 300, or 1000 mg/kg/day. Male rats were dosed for 29 days and female rats were dosed from 14 days prior to mating through Day 3 of lactation. On the basis of the results obtained in this study, there were no significant signs of general systemic toxicity and fertility up to 1000 mg/kg/day for males and females. The NOAEL for effects on fertility was found to be 1000 mg/kg/day males and females.

Methacrylates and the vinyl group do not cause effects on fertility as illustrated by MMA, for which a 2 generation study is available and more than ten other negative 422 screening studies with a wide variety of methacrylate esters. Furthermore, higher glycol ethers, for example ethoxydiethyleneglycol, a lower ethoxylated analogue of ethoxytriethylene glycol, as well as butyldiglycol, the parent alcohol of BDGMA do not appear to affect fertility.

The primary metabolite of BDGME, the alcohol Butyldiglycol, did not show adverse effects on fertility of male and female rats at a dose of 2000 mg/kg/day when administered dermally over a 13 week period to both sexes and to the females additionally throughout the gestation and lactation period.

In conclusion there is no indication for Butyldiglycol methacrylate to produce reprotoxic effects. The generated NOAEL for BDGMA in an OECD 422 repeated dose and reproductive toxicity screening study was determined to be 1000 mg/kg bw/day.


Short description of key information:
OECD 422 reproductive toxicity screening study with Butyldiglycol methacrylate: Reproductive NOAEL 1000 mg/kg, no apparent systemic toxicity up to 1000 mg/kg (Klimisch score: 1, guideline study, GLP) (HRTF, 2014).
Supporting information: No indication to reproductive toxicity for primary metabolites butyldiglycol and methacrylic acid.

The primary metabolite of BDGME, the alcohol Butyldiglycol, did not show adverse effects on fertility of male and female rats at a dose of 2000 mg/kg/day when administered dermally over a 13 week period to both sexes and to the females additionally throughout the gestation and lactation period.

Justification for selection of Effect on fertility via oral route:
In a reproductive toxicity screening study according to OECD 422 with Butyldiglycol methacrylate in rats, no impact on fertility was observed (reliability 1, guideline study, GLP).

Justification for selection of Effect on fertility via dermal route:
Pivotal metabolite, relevant pathway of exposure

Effects on developmental toxicity

Description of key information
OECD 422 reproductive toxicitry screening study: Developmental and systemic NOAEL 1000 mg/kg (Klimisch score: 1, guideline study, GLP) (HRTF, 2014).
Developmental toxicity studies with primary metabolites:
Methacrylic acid: Saillenfait et al. (1999); Developmental study in rats; No effects on development up to 300 ppm (1232 mg/m³), equivalent to a body burden of 409 mg/kg/d.
Butyldiglycol: Review of several developmental toxicity studies (ECETOC 2005, MAK 2008) up to 2050 mg/kg/d, no specific developmental effects.
Link to relevant study records

Referenceopen allclose all

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
27 August to 22 October 2013
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: compliance to GLP and testing guideline, coherence between data, results and conclusions
Qualifier:
according to
Guideline:
other: OECD Guideline 422
Deviations:
no
GLP compliance:
yes (incl. certificate)
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Details on test animals and environmental conditions:
TEST ANIMALS
A total of 90 Sprague Dawley [Crl:CD(SD)BR] rats (45 males and 45 virgin females), 6 to 7 weeks old and weighing 190 - 217 g for males and 175 - 189 g for females, were received from Charles River Italia S.p.A., Italy.
After arrival the weight range for each sex was determined and the animals were temporarily identified within the cage by means of a coloured mark on the tail. A health check was then performed by a veterinarian.
An acclimatisation period of 13 days was allowed before the start of treatment, during which time the health status of the animals was assessed by thorough observations.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C +/- 2°C
- Humidity (%): 55% +/- 15%
- Air changes (per hr): 15 to 20 air changes per hour
- Photoperiod (hrs dark / hrs light): artificial light for 12 hours each day
No relevant deviations from these ranges were recorded during the study.

In-life phase: August 2013 to 22 October 2013
Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
The test item was administered orally by gavage at a dose volume of 5 mL/kg body weight. Control animals received the vehicle alone at the
same dose volume.

The required amount of Butyl diglycol methacrylate was suspended in the vehicle (corn oil) and brought to the final volume appropriate for each
concentration (concentrations of 20, 60 and 200 mg/mL) and kept under magnetic stirrer at room temperature prior to use and until the time of dosing of the last animal.
The formulations were prepared daily and the concentrations were calculated and expressed in terms of test item as supplied.

Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Prior to commencement of treatment, analysis was performed to confirm that the proposed formulation procedure was acceptable (concentration
and homogeneity). Results of the analyses were within the limits of acceptance.
The stability was found to be 24 hours at room temperature in the concentration range of 20 to 200 mg/mL.
Samples of the formulations prepared on Week 1 and last Week were also analysed to check the concentration and homogeneity. Results of the analyses were within the limits of acceptance.
Chemical analysis was carried out by the Analytical Chemistry Department at RTC according to a validated method (RTC Study No. 96370), in the range from 5 to 200 mg/mL.
Details on mating procedure:
Mating was monogamous (one male to one female). A vaginal smear was taken from the day after the start of pairing until positive identification of
copulation (sperm identification, vaginal plug in situ or copulation plugs found in the cage tray).
The female was paired with the same male until positive identification occurred or 14 days had elapsed.
Duration of treatment / exposure:
Males
Animals were dosed once a day, 7 days a week, for a minimum of 2 consecutive weeks prior to pairing and thereafter through the day before necropsy
(Day 29 - 30 of treatment).

Dose volumes were adjusted once per week for each animal according to the last recorded body weight.

Females
Animals were dosed once a day, 7 days a week, for a minimum of 2 consecutive weeks prior to pairing and thereafter during pairing, post coitum and
post partum periods until Day 3 post partum (the day before sacrifice).

Dose volumes were adjusted once per week for each animal according to the last recorded body weight.
During the gestation period, dose volumes were calculated according to individual body weight on Days 0, 7, 14 and 20 post coitum and on Day 1
post partum. Thereafter individual dose volumes remained constant.
Frequency of treatment:
once daily
No. of animals per sex per dose:
The test item was administered orally, by gavage. The oral route was selected as it is a possible route of exposure of the test item in man.
3 groups comprised 10 males and 10 females rats received the test item at the dose levels of 100, 300 and 1000 mg/kg/day.
Each group comprised 10 male and 10 female rats.
Control animals:
yes
Details on study design:
Dose levels of 100, 300 and 1000 mg/kg/day were selected by the Sponsor based on information from a previous non GLP compliant study (2 week preliminary study) (RTC Study no.: 96020EXT).
Maternal examinations:
CAGE SIDE OBSERVATIONS: No

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once before commencement of treatment, at least once daily during the study

BODY WEIGHT: Yes
- Time schedule for examinations: males: weekly from allocation to termination
females: weekly from allocation topositive identification of mating and on gestation days 0, 7, 14 and 20

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
The weight of food consumed by each cage of males and females was recorded weekly during the pre-mating period starting from allocation.
Individual food consumption for the females was measured on gestation Days 7, 14 and 20 starting from Day 0 post coitum and on Day 4 post
partum starting from Day 1 post partum.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day: Day 4 post partum
- Organs examined: please see Annex 1 (Any other information on materials and methods incl. tables)

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
Fetal examinations:
yes
Statistics:
Standard deviations were calculated as appropriate. For continuous variables the significance of the differences amongst group means was assessed by Dunnett’s test or a modified t test, depending on the homogeneity of data.
Statistical analysis of histopathological findings was carried out by means of the non-parametric Kolmogorov-Smirnov test if n was more than 5. The
non-parametric Kruskal-Wallis analysis of variance was used for the other parameters. Intergroup differences between the control and treated
groups were assessed by the non-parametric version of the Williams test. The criterion for statistical significance was p<0.05. The mean values,
standard deviations and statistical analysis were calculated from actual values in the computer without rounding off.
Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
not examined
Behaviour (functional findings):
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Neuropathological findings:
no effects observed
Description (incidence and severity):
Motot activity and sensory reaction to stimuli revealed in no relevant differences in all parameters investigated between control and treated groups of both sexes.
Histopathological findings: non-neoplastic:
no effects observed
Number of abortions:
no effects observed
Pre- and post-implantation loss:
no effects observed
Total litter losses by resorption:
no effects observed
Early or late resorptions:
no effects observed
Dead fetuses:
no effects observed
Changes in number of pregnant:
no effects observed
Key result
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day
Based on:
test mat.
Basis for effect level:
other: developmental toxicity
Fetal body weight changes:
no effects observed
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
Skeletal malformations:
no effects observed
Visceral malformations:
no effects observed
Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:no effects
Key result
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: no effects observed
Key result
Abnormalities:
no effects observed
Developmental effects observed:
not specified
Conclusions:
On the basis of the results obtained in this study with Buty diglycol methacrylate, the NOAEL (No Observed Adverse Effect Level) for
developmental toxicity was found to be 1000 mg/kg/day for males and females.
Executive summary:

In a Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test according to OECD Guideline 422 (22 March 1996) Butyl diglycol methacrylate was administered to 10 Hsd: Sprague Dawley SD rats/sex/dose orally by gavage at dose levels of 0 (control), 100, 300 and 1000 mg/kg bw/d. The treatment schedule included 2 weeks before pairing for males and during pairing with females until the day before necropsy, for a total of 29/30 days. Females were treated for 2 weeks prior to pairing, during pairing and throughout the gestation and lactation periods until Day 3 post partum. The following investigations were performed in all groups: body weight, clinical signs (including neurotoxicity assessment, motor activity and sensory reaction to stimuli), food consumption, oestrous cycle, mating performance, clinical

pathology investigations (haematology and clinical chemistry), litter data, macroscopic observations, organ weights and histopathological examination. Clinical signs and macroscopic observations of pups were also performed. The histopathological examination was performed only on control and high dose groups (five animals/sex/group selected randomly). It included identification of the stages of the spermatogenic cycle in five males.

No animals died during the study. A total of 3 females were found not pregnant at necropsy: 2 in the mid-dose group and 1 in the high dose group. The number of females with live pups on Day 4 post partum was: 10 each in the control ad low dose groups, 8 in the mid-dose and 9 in the high dose groups.

No relevant clinical signs were seen throughout the whole study in treated animals of both sexes.

Clinical observations for neurotoxicity assessment (removal of animals from the home cage and open arena) did not reveal changes attributable to the test item.

Motor activity and sensory reaction to stimuli revealed in no relevant differences in all parameters investigated between

control and treated groups of both sexes.

No differences of toxicological significance in body weight and body weight gain were recorded in animals of both sexes compared to the control group, throughout the study.

Food consumption was unaffected by treatment in both sexes during the study.

Haematology: No changes of toxicological relevance were seen.

Clinical chemistry: No adverse findings were detected at any dose.

All females mated both in the control and treated groups. Oestrous cycle, precoital intervals, copulatory index and fertility index did not show intergroup differences.

Corpora lutea, implantations, pre-implantation and pre-birth loss percentages, total litter size and gestation length did not reveal any treatment-related effect. No differences in total and live litter size, litter weight, mean pup weight and sex ratio were noted between groups at birth and on Day 4 post partum.

Clinical signs noted in pups throughout the study were considered unrelated to treatment.

Necropsy findings in decedent pups and in pups sacrificed on Day 4 post partum did not reveal any treatment-related effect.

Terminal body weight was unaffected by treatment in both sexes. Changes in organ weights were of slight severity and therefore considered of no toxicological significance.

Macroscopic observations: No remarkable changes were noted at post mortem examination in treated animals when compared to controls.

Microscopic observations: No treatment-related findings were observed in high dose males and females.

Conclusions:

This study is acceptable and satisfies the guideline requirement for a Screening reproductive/developmental study according to OECD 422 in rats.

On the basis of the results obtained in this study, the NOAEL (No Observed Adverse Effect Level) for general toxicity was considered to be 1000 mg/kg/day for males and females.

The NOAEL for developmental and reproductive toxicity was also found to be 1000 mg/kg/day for males and females.

Endpoint:
developmental toxicity
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Study period:
1993
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well documented and in accordance to scientifically accepted principles, minor deviations to OECD guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
90 days exposure of males and females pre-mating, mating, females were traeted through day day 20 of gestation and allowed to deliver and nurse their offspring through day 21 of lactation (weaning)
GLP compliance:
not specified
Limit test:
yes
Species:
rat
Strain:
other: CD
Details on test animals and environmental conditions:
- Source: CharlesRiver Lab., Raleigh,NC (USA)
- Age at study initiation: 8 weeks

- Housing: individually in suspended stainless steel cages
- Diet: Certified Purina Rodent Chow ad libitum
- Water: from Elizabethtown Water Company, ad libitum):
- Acclimation period: 2 weeks
Route of administration:
dermal
Vehicle:
unchanged (no vehicle)
Details on exposure:
- Area of exposure: back
- % coverage: 3 x 3 cm area
- Type of wrap if used: polyethylene patch, covered by an adhesive bandage wrapped around the trunk

REMOVAL OF TEST SUBSTANCE
- Washing (if done): residual test material was gently wiped from the application site
- Time after start of exposure: 6 hrs

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg/d
- Concentration: undiluted
- Constant volume or concentration used: yes

Analytical verification of doses or concentrations:
yes
Details on mating procedure:
No
Duration of treatment / exposure:
Males: 13 weeks pre-mating , then until mating was finished
Females: 13 weeks pre-mating and thereafter gestation period (20 days) and lactation period (21 days)
Frequency of treatment:
Males and females : 5 days/ week, 6 hrs/day pre-mating
Females: 7 days/week, 6 hrs/day during gestation and lactation period
Duration of test:
90 days pre-mating and then throughout gestation and lactation period until day 21 post partum.
No. of animals per sex per dose:
25
Control animals:
yes
Maternal examinations:
CAGE SIDE OBSERVATIONS: Yes

DETAILED CLINICAL OBSERVATIONS: Yes

BODY WEIGHT: Yes

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined : Yes
Fetal examinations:
- External examinations: Yes
Statistics:
Bartlett's test / ANOVA (parametric procedures)
Kruskal-Wallis test (non-parametric procedures)
Furtherly used: Dunn's summed-rank test; Jonckheere's test for monotonic trends for nonparametric comparisons; Fisher exact test.
Indices:
Number of litters: dose group: 19; controls: 20
Mean gestation length (days): dose group .21.4; controls: 21.5

Mean number of pups at birth day (day 0):
dose group: live: 13.9; dead: 0.4; total: 14.3
controls: 14.2; dead: 0.4; total: 14.6

Pups survival indices
Day 0-4
dose group :97.0 %
controls: 95.4 %

Day 4-21
dose group: 100.0 %
controls: 96.3 %

Mean pup weights [g]
Day 0: dose group: 6.8; controls: 6.8
Day 4: dose group: 10.4; controls: 10.5
Day 14: dose group: 35.5; controls: 35.6
Day21: dose group: 53.8; controls: 53.4
Details on maternal toxic effects:
Maternal toxic effects:no effects. Remark: systemic
Dose descriptor:
NOAEL
Effect level:
2 000 mg/kg bw/day
Based on:
test mat.
Basis for effect level:
other: developmental toxicity
Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:no effects
Dose descriptor:
NOAEL
Effect level:
2 000 mg/kg bw/day
Based on:
test mat.
Basis for effect level:
other: teratogenicity
Abnormalities:
not specified
Developmental effects observed:
not specified
Conclusions:
Butyldiglycol showed no effects on reproduction parameters in parental rats and offspring when administered dermally for 13 weeks
Executive summary:

The alcohol Butyldigylycol (CAS 112-34-5) was tested for toxicity to reproduction in a well conducted repeated dose study in rats (25 animals per sex and dose group). The substance was applied dermally at a dose of 2000 mg/kg to males for 90 days pre-mating and until mating was successful. Females were exposed 90 for days pre-mating and during the gestation (20 days) and lactation period (21 days). Parental animals showed no substance induced effects on fertility, reproductive indices did not differ from controls. Litters delivered were allowed to grow until the end of lactation. They showed no signs of teratogenicity or fetotoxicity and no deviation to controls in offspring viability indices. There was no evidence for systemic toxicity by clinical and histopathological evaluations for all animals. Therefore, the NOAEL of the study can be determined to 2000 mg/kg/d.

Effect on developmental toxicity: via oral route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
subacute
Species:
rat
Quality of whole database:
Screening level data available from OECD 422 study, supported by developmental toxicity data from primary metabolites methacrylic acid and butyldiglycol, both indicating an absence of developmental toxicity.
Effect on developmental toxicity: via inhalation route
Endpoint conclusion:
no study available
Effect on developmental toxicity: via dermal route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
2 000 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
Publication; well documented and in accordance to scientifically accepted principles
Additional information

Butyldiglycol methacrylate was studied in an OECD 422 combined repeat dose and reproductive/developmental toxicity screening test (HRTF, 2014). Groups of 10 male and 10 female rats were administered by gavage at dose levels of 0, 100, 300, or 1000 mg/kg/day. Male rats were dosed for 29 days and female rats were dosed from 14 days prior to mating through Day 3 of lactation. On the basis of the results obtained in this study, there were no significant signs if toxicity and fertility/developmental toxicity up to 1000 mg/kg/day for males and females. The NOAEL for systemic and developmental/reprotoxic effects was found to be 1000 mg/kg/day.

In terms of the primary metabolites, methacrylic acid (MAA), the common metabolite for all the esters, also was tested in groups of 19-25 pregnant female rats (whole-body inhalation exposure for 6 hr/day, during days 6 to 20 of gestation), at 0, 50, 100, 200, and 300 ppm (0, 179, 358, 716 and 1076 mg/m3) produced no embryo- or foetal lethality, nor foetal malformations after exposure with MAA at any concentration, despite overt maternal toxicity (decreased body weight and feed consumption) at 300 ppm (1076 mg/m3). The NOAEL for developmental toxicity was considered 300 ppm (1076 mg/m3) MAA (Saillenfait et al., 1999).

There was neither indication of teratogenicity or fetotoxicity nor of developmental effects in a subchronic study on rats with dermal exposure to Butyldigylycol, which is a pivotal metabolite of BDGMA.

 

With respect to the alcohol moiety, Butyldiglycol did not show specific developmental effects when tested up to 2050 mg/kg (ECETOC 2005, MAK 2008). Moreover, there are no alerts regarding specific developmental toxicity for the structurally similar members of the methacrylate esters category and the simple glycols (ethylene and propylene glycol; ATSDR 2010; ATSDR 1997 and 2008) and the complex glycol ethers (diethylene glycol butyl ether, DEGBE and trietheylene glycol monomethyl ether, TEGEE; Leber et al. 1990, ECETOC, 2005).

Justification for selection of Effect on developmental toxicity: via oral route:
Available reproductive toxicity screening study, reliability 1, GLP

Justification for selection of Effect on developmental toxicity: via dermal route:
Pivotal metabolite, relevant pathway of exposure

Justification for classification or non-classification

Overall, in consideration of all data available for BDGMA and its metabolites, there is no convincing evidence of reproductive toxicity and a general absence of developmental effects.

In summary, classification of Butyldiglycol methacrylate for reproductive toxicity is not required.