2-(2-ethoxyethoxy)ethyl acrylate

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October 2016 to May 2017

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

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

Remarks:

These minor discrepancies: slightly heavier male rats and one week older than written in the protocol. Considered to have no impact on the integrity of the study.

Principles of method if other than guideline:

NA

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-ethoxyethoxy)ethyl acrylate

EC Number:

230-811-7

EC Name:

2-(2-ethoxyethoxy)ethyl acrylate

Cas Number:

7328-17-8

Molecular formula:

C9H16O4

IUPAC Name:

2-(2-ethoxyethoxy)ethyl acrylate

Test material form:

other: clear, colorless liquid

Details on test material:

- Name of test material (as cited in study report): EOEOEA
- Physical state: clear colourless liquid
liquid
- Analytical purity: 2- (2-ethoxyethoxy)ethyl acrylate, CAS RN 7328-17-8: 92.1% (by GLC)
- Purity test date:
- Lot/batch No.: EA633
- Expiration date of the lot/batch: 01 June 1999
- Stability under test conditions: Stable
- Storage condition of test material: In refrigerator in the dark

Specific details on test material used for the study:

- Name of test material (as cited in study report): MIRAMER M170
- Physical state: Clear colorless liquid
- Analytical purity: 95.49% ( CAS No.: 7328-17-8; EC No.: 230-811-7)
- Impurities (identity and concentrations): Ethyl Carbitol 0.99%, 2-Ethoxy ethyl acrylate(EOEA) 0.14%, EOEOA/AA 1.28%, EOEOEA dimer 2.11%.
- Lot/batch No.: 151210177
- Expiration date of the lot/batch: 30 June 2017
- Storage condition of test material: At ambient temperature (10 to 30 degree celcius) and protected from light (although could be used for formulation in light).
Supplier: Miwon

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Rat, RccHan®:WIST from Harlan Laboratories Models, S.L.
- Age at study initiation: Males 76 to 83 days old and females 90 to 97 days old.
- Weight at study initiation: Males: 360 to 446 g Females: 239 to 306 g.
- Fasting period before study: No.
- Housing:Solid (polycarbonate) bottom cages were used during the acclimatization, pre-pairing, gestation, littering and lactation periods. Grid bottomed polypropylene cages were used during pairing. These were suspended above absorbent paper which was changed daily during pairing.,Solid bottom cages contained softwood based bark-free fiber bedding which was changed at appropriate intervals each week..
- Diet: SDS VRF1 Certified pelleted diet - ad libitum.
- Water: Tap water ad libitum
- Acclimation period: Males six days and females 20 days before commencement of treatment.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): air-conditioned with ranges for room temperature 20 -24 °C
- Humidity (%): relative humidity 40-70%
- Air changes (per hr): not specified.
- Photoperiod (hrs dark / hrs light): a 12-hour fluorescent light/12-hour dark cycle

IN-LIFE DATES: From: To: 7 December 2016 to 5 February 2017

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: The stock solution was prepared by weighing the necessary amount of test item in an appropriate The required amount of test item was weighed out and approximately 50% of the final volume of vehicle was added. It was magnetically stirred until the test material was uniformly mixed. It was made up to the required volume with vehicle and mixed again with a magnetic stirrer until homogenous.

VEHICLE
- Justification for use and choice of vehicle (if other than water): Corn oil is a generally recognized vehicle
- Concentration in vehicle: 0, 5, 15 and 45 mg/mL
- Amount of vehicle (if gavage): 5 mL/kg body weight.
- Lot/batch no. (if required): NA
- Purity: NA

Details on mating procedure:

- M/F ratio per cage: 1:1 from within the same treatment groups.
- Length of cohabitation: 14 days
- Proof of pregnancy: The daily vaginal smear was sperm-positive, or/and a copulation plug was observed. referred to as day 0 postcoitum
- After 14 days of unsuccessful pairing replacement of first male by another male with proven fertility.
- Further matings after two unsuccessful attempts: No
- After successful mating each pregnant female was caged (how): housed individually
- Any other deviations from standard protocol: No

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Fresh preparations were made weekly and stored refrigerated (2-8°C).

For each day of administration, the necessary volume was taken from the stock solution into appropriate containers. The aliquots were stored at room temperature (20 ± 5 ºC) protected from light.

Stability and homogeneity:
Before commencement of treatment, the suitability of the proposed mixing procedures was determined and specimen formulations at 1 and 200 mg/mL were analyzed to assess the stability and homogeneity of the test item in the liquid matrix. Stability of the test item was confirmed for one day at ambient temperatures (15-25°C) or for 15 days when stored refrigerated (2-8°C).

Achieved concentration:
Samples of each formulation prepared for administration in Week 1 of treatment and on Day 12 of lactation were analyzed for achieved concentration of the test item.

Duration of treatment / exposure:

Males were treated daily for two weeks before pairing, up to necropsy after a minimum of five consecutive weeks.
Females were treated daily for two weeks before pairing, throughout pairing, gestation and until Day 13 of lactation.

Frequency of treatment:

Once daily

Details on study schedule:

Females were allowed to litter, rear their offspring and were killed on Day 14 of lactation.
The F1 generation received no direct administration of the test item; any exposure was in utero or via the milk. The F1 offspring were killed on Day 13 of age.

A similarly constituted Control group received the vehicle, corn oil, at the same dose volume as treated groups.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

0 mg/kg bw/day (actual dose received)

Remarks:

Group 1 (vehicle control)

Doses / concentrations 2

Dose / conc.:

25 mg/kg bw/day (actual dose received)

Remarks:

Group 2

Doses / concentrations 3

Dose / conc.:

75 mg/kg bw/day (actual dose received)

Remarks:

Group 3

Doses / concentrations 4

Dose / conc.:

225 mg/kg bw/day (actual dose received)

Remarks:

Group 4

No. of animals per sex per dose:

80 in total (40 males and 40 females):

Group 1 (0 mg/kg): 10 M/10F
Group 2 (25 mg/kg): 10 M/10F
Group 3 (75 mg/kg): 10 M/10F
Group 4 (225 mg/kg): 10 M/10F

Control animals:

yes, concurrent vehicle

Details on study design:

Dose selection rationale:

The dose levels were selected in conjunction with the Sponsor, based on the results of the 2-week preliminary toxicity study in the Sprague Dawley rat (Envigo Study No. SJ71TP). Using doses up to 1000 mg/kg/day. Death was observed in the group dosed 1000 mg/kg/day (due to serosal inflammation/peritonitis) and doses at 325 mg/kg/day caused stomach ulceration.

Based on findings in the 2-week study the highest dose in the present study was set to 225 mg/kg/day a dose that induce some toxicity, but not severe toxicity or death. Intermediate and low doses were set at 75 and 25 mg/kg/day to allow evaluation of any dose related trends. The low dose of 25 mg/kg/day was expected to be a no effect level for stomach lesions


- Rationale for animal assignment (if not random): Randomization method based on the similarity of the mean body weights among the groups.

Positive control:

No

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: At least twice daily for mortality and for signs of reaction to treatment and/or symptoms of ill health before dosing and post dosing.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Before treatment commenced and during each week of treatment and on Days 0, 7, 14 and 20 after mating and Days 1, 6 and 12 of lactation, detailed physical examination and arena
observations were performed on each animal. These observations were performed outside the home cage, in a standard arena, at least two hours after dosing (where applicable) to ensure that any transient effects of treatment are identified. All observations were recorded.

BODY WEIGHT: Yes
- Time schedule for examinations:
F0 males: Before dosing on the day that treatment commenced (Week 0) and weekly thereafter. On the day of necropsy.

F0 females: Before dosing on the day that treatment commenced (Week 0) and weekly before pairing. Days 0, 6, 13 and 20 after mating. Day 1, 4, 7 and 13 of lactation. On the day of necropsy.

FOOD CONSUMPTION AND COMPOUND INTAKE:
- Weekly, from the day that treatment commenced.
For females after mating food consumption was performed to match the body weight recording: Days 0-5, 6-12 and 13-19 after mating Days 1-3, 4-6 and 7-12 of lactation. From these records the mean weekly or daily consumption per animal (g/animal/week or g/animal/day) was calculated for each phase.
No food consumption was examined during the mating period, with exception for males in week 4.

WATER CONSUMPTION AND COMPOUND INTAKE: not specified.

Clinical Laboratory Investigations:
Blood samples were collected after overnight withdrawal of food at the following occasion: Animals were held under light general anesthesia induced by isoflurane. Blood samples (nominally 0.5 - 0.7 mL) were withdrawn from the sublingual vein, collected into tubes containing EDTA anticoagulant or lithium heparin as anticoagulant and examined for hematology or blood chemistry. Blood film (prepared for all samples) - Romanowsky stain, examined for abnormalities by light microscopy, in the case of flags from the Advia 120 analyzer. Confirmation or a written description from the blood film was made where appropriate.

In addition, blood samples were collected from animals for Thyroid Hormone Analysis at the following occasions:
-At termination: All surviving F0 adult males and females
-Day 4 of age: F1 offspring, two females per litter (where possible)* one for T4 and one for TSH.
* No pups were eliminated where the resultant litter size would have dropped below ten per litter.


Sensory reactivity and grip strength assessments (Approach response, Pinna reflex, Auditory startle reflex, Tail pinch response, and Grip strength) were performed (before dosing) on the five lowest numbered surviving males in each group during Week 5 of treatment and on the five lowest numbered surviving lactating females in each group at Day 7-9 of lactation.
For females, animals were moved into individual cages prior to transport to the testing room.

During Week 5 of treatment for males and at Day 7-9 of lactation for females, the motor activity of the five lowest numbered surviving males and the five lowest numbered surviving lactating females in each group was measured (before dosing) using a Rodent Activity Monitoring System (Version 2.0.6), with hardware supplied by Pearson Technical Services and software developed and maintained by Envigo.

Oestrous cyclicity (parental animals):

Vaginal smears were taken as follows:
Dry smears: For 15 days before pairing using cotton swabs
Wet smears: Using pipette lavage during the following phases:
• For 14 days before treatment (all females including spares); animals that failed to exhibit 4-5 day cycles were not allocated to study.
• After pairing until mating.
• For four days before scheduled termination (nominally Day 11 to 14 of lactation).offspring.

Sperm parameters (parental animals):

F0 male parental generations: A qualitative staging of spermatogenesis and histopathology evaluation of interstitial cells of all males from the control and high-dose groups was performed. Further, the weight of testes was recorded. Parameters examined in [P] male parental generations:
[epididymis weight, sperm count in testes, sperm count in epididymides, sperm morphology, other:]

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: [no]
PARAMETERS EXAMINED
The following parameters were examined in [F1] offspring:
[number and sex of pups, live births, postnatal mortality, presence of gross anomalies, weight gain, , anogenital distance (AGD), presence of nipples/areolae in male pups,:]

GROSS EXAMINATION OF DEAD PUPS:
[yes, for external and internal abnormalities.]

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: At least on day 44 of the study all surviving males were deeply anaesthetized with sodium pentobarbital administered intraperitoneally, exsanguinated and necropsied.
- Maternal animals: On day 5 postpartum, all females were deeply anaesthetized with sodium pentobarbital administered intraperitoneally, exsanguinated and necropsied. The mated females that did not give birth or show signs of pregnancy were sacrificed after 24-26 days postcoitum if no repeat
mating was done.

GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations. The necropsy included the examination of the external surface of the body, all orifices, cranial, thoracic and abdominal cavities and the observation of the organs both in situ and after evisceration.
Samples of tissues and organs described in the OECD 422 test guideline including reproductive organs were collected from all animals at necropsy and fixed in neutral phosphate buffered 4% formaldehyde solution (10% formalin).

HISTOPATHOLOGY / ORGAN WEIGTHS
- The following organs were weighed on the day of necropsy and their organ to terminal body weight ratios and organ to brain weight ratios were determined:
Adrenals *; Kidneys*; Prostate and seminal vesicles; Thyroid and parathyroids *; Brain Liver Spleen Uterus and oviducts; Epididymides*; Ovaries* Testes*; Heart Pituitary Thymus (* Paired organs were weighed together).

- All organ and tissue samples, except for the nose, to be examined by the study pathologist were processed, embedded and cut at an approximate thickness of 2-4 micrometers and stained with hematoxylin and eosin. The bone marrow smears were stained using the May Grünwald-Giemsa method.

- Slides of all organs and tissues collected at necropsy from five males and five females from groups 1 and 4 selected for clinical pathology, as well as all gross lesions, were examined. Reproductive organs (tissues shown in bold) from all control and high dose animals were examined for histopathology. Because test-item-related morphological changes were detected in stomach and liver at high dose, these organs of all remaining animals (including group 2 and 3) were examined. A description of all abnormalities was included in the report. Where possible, the microscopic findings were correlated with the gross observations.
A copy of the histopathology report is included in the test report.

Postmortem examinations (offspring):

SACRIFICE
-Sacrifice of F0 females at Day 14 of lactation (following terminal blood sampling) exsanguinated and necropsied. F0 females failing to produce a viable litter: killed at Day 25 after mating using carbon dioxide asphyxiation with subsequent exsanguination and then necropsied

-Sacrifice of F0 Males
At week 5 of the study all males were killed using carbon dioxide asphyxiation with subsequent exsanguination and then necropsied.

-Sacrifice of F1 Generation:
Selected offspring for Day 4 thyroid hormone analysis were killed at Day 4 of age and Scheduled kill offsprings at Day 13 of age by decapitation.
Offspring - not selected for thyroid hormone sampling killed by Intraperitoneal injection of sodium pentobarbitone.


GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations. The necropsy included the examination of the external surface of the body, all orifices, cranial, thoracic and abdominal cavities and the observation of the organs both in situ and after evisceration.
Tissues were routinely preserved in 10% Neutral Buffered Formalin with the exception of testes which was Initially fixed in modified Davidson’s fluid and eyes In Davidson’s fluid.

HISTOPATHOLOGY / ORGAN WEIGTHS
- The tissues indicated in Table 1 and 2 under "other information on materials and methods" were prepared for microscopic examination and weighed, respectively

Statistics:

All statistical analyses were carried out separately for males and females using the individual animal as the basic experimental unit. For litter/fetal findings the litter was taken as the treated unit and the basis for statistical analysis and biological significance was assessed with relevance to the severity of the anomaly and the incidence of the finding within the background control population.

The following sequence of statistical tests was used for grip strength, motor activity, body weight, food consumption, clinical pathology, litter size and survival indices, ano-genital distance and organ weight data. Comparisons were performed between Group 1 vs 2, 3 and 4.

Parametric analysis (t-test and ANOVA, Willliams test, or Dunnetts test) was performed if Bartlett's test for variance homogeneity was not significant at the 1% level and i significant at 1% level after both logarithmic and square-root transformations a non-parametric analysis (Kruskal-Wallis, Wilcoxon rank sum test, shirley's or steel's test) was performed

For grip strength, motor activity, clinical pathology, litter size and survival indices, if 75% of the data (across all groups) were the same value, for example c, Fisher’s exact tests were performed.
Sex ratio was analyzed by generalized mixed linear model with binomial errors, a logit link function and litter as a random effect (Lipsitz 1991).
For gestation length an exact two-tailed Linear-by-linear test (Cytel 1995), with equally spaced scores, was applied to all groups.

Significant differences between the groups compared were expressed at the 5% (p<0.05) or
1% (p<0.01) level.

Reproductive indices:

-Post-implantation survival index (%)
-Live birth index (%)
-Viability index (%)
-Lactation index (%)

Offspring viability indices:

The following were calculated for each litter:

Post-implantation survival index (%) = (Total number of offspring born/Total number of uterine implantation sites) x 100

Post-implantation survival index was expressed as 100% where the number of offspring
exceeded the number of implantation sites recorded.

Live birth index (%) = (Number of live offspring on Day 1 after littering/ Total number of offspring born) x 100

Viability index (%) = (Number of live offspring on Day 4 (before blood sampling)/Number live offspring on Day 1 after littering) x 100

Lactation index (%) = (Number of live offspring on Day 13 after littering/ Number of live offspring on Day 4 (after blood sampling)) x 100

Group mean values were calculated from individual litter values.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

Hematological examination revealed high mean total and differential leucocyte counts and large unstained cell counts in males treated at 225 mg/kg/day when compared with controls.

In females treated at 25, 75 or 225 mg/kg/day red cell distribution width was high when compared with controls attaining statistical significance at all levels, however the magnitude of change from controls showed no correlation to a dose-related trend. Platelet counts were observed to be low in females treated at 225 mg/kg/day when compared with controls attaining statistical significance however there was no relationship to dose level with values at 25 mg/kg/day and 75 mg/kg/day

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

Biochemical evaluation revealed no clear effect of treatment.

In males and females treated at 225 mg/kg/day, marked increases in mean alanine phosphatase and aspartate transferase concentrations were observed, however a review of the individual data attributed this finding to markedly increased levels for both parameters in one male and one female (Nos. 2 and 46 respectively). No relationship to treatment is inferred.

Urinalysis findings:

not examined

Behaviour (functional findings):

effects observed, non-treatment-related

Description (incidence and severity):

Motor activity was considered to be unaffected by treatment.

Among males, the only statistically significant intergroup difference was that mean high beam scores in all groups of treated males were lower than Controls at 18 minutes; there was no dose response. This isolated difference was considered to have arisen by chance and to be unrelated to treatment.

Motor activity scores for females treated with Ethoxy ethoxy ethyl acrylate were comparable to Controls.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Changes related to treatment with Ethoxy ethoxy ethyl acrylate were seen in the stomach of both males and females and pancreatic lymph nodes of males.

These consisted of diffuse hyperplasia of the squamous epithelium, with a focal to multifocal exophytic growth pattern, along with hyperkeratosis, inflammation of the mucosa and submucosa (occasionally extending down the muscle and serosal layers at the high dose), as well as focal to multifocal erosions/ulcerations in some animals.

In the glandular region of the stomach of a few females treated at 75 or 225 mg/kg/day (1/10 and 3/10 respectively), focal to multifocal areas of slight to moderate mucosal necrosis or erosion were observed.

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

no effects observed

Description (incidence and severity):

All females allocated to the study showed regular 4 or 5 day estrus cycles prior to the start of treatment. There was no effect of treatment on the stage of the estrus cycle during treatment or at termination.

Reproductive function: sperm measures:

not examined

Reproductive performance:

effects observed, treatment-related

Description (incidence and severity):

In females treated at 225 mg/kg/day a shift in gestation length was observed with more
females in group 4 showing a 22 day gestation length and less females in group 4 showing a
23 day gestation length, when compared with Controls; this difference attained statistical
significance.

Pre-coital interval, mating performance and fertility were unaffected by treatment with
Ethoxy ethoxy ethyl acrylate.

Effect levels (P0)

1

Key result

Dose descriptor:

NOAEL

Effect level:

25 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: F0 generation, stomach irritation/inflammation.

2

Key result

Dose descriptor:

NOAEL

Effect level:

225 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no systemic or reproductive effects

Target system / organ toxicity (P0)

Key result

Critical effects observed:

yes

Lowest effective dose / conc.:

75 mg/kg bw/day (actual dose received)

System:

gastrointestinal tract

Organ:

stomach

Treatment related:

yes

Dose response relationship:

yes

Relevant for humans:

yes

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Description (incidence and severity):

Waiting for Data on Thyroid hormone

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

There were no findings in any decedent offspring, or in any offspring at termination on Day 13 of age, that were considered to be related to treatment.

On Day 13 of age, one male and two female offspring from litter 45 (225 mg/kg/day) were observed to have a domed cranium with dilated lateral ventricles of the brain. As this finding was confined to one litter it is considered likely the result of natural biological variation and is considered not to be attributable to treatment.

Histopathological findings:

not examined

Other effects:

no effects observed

Description (incidence and severity):

Ano-genital distance in male and female offspring were unaffected by treatment.

A check was performed to assess for the presence or absence of nipple/areolae for the male
offspring. There were no counts and consequently no data are presented in this report.

Developmental neurotoxicity (F1)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F1)

Developmental immunotoxicity:

not examined

Details on results (F1)

-Ano-genital distance in male and female offspring were unaffected by treatment.

-A check was performed to assess for the presence or absence of nipple/areolae for the male
offspring. There were no counts and consequently no data are presented in this report.

-Litter size, sex ratio and offspring survival were unaffected by treatment with Ethoxy ethoxy
ethyl acrylate.

Effect levels (F1)

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

225 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No treatment-related developmental toxicity at highest tested dose level (225.0 mg/kg bw/day)

Target system / organ toxicity (F1)

Key result

Critical effects observed:

no

Overall reproductive toxicity

Key result

Reproductive effects observed:

no

Any other information on results incl. tables

Summary table of treatment related findings in the stomach for animals killed at the end of treatment:

Group/sex	1M	2M	3M	4M	1F	2F	3F	4F
Dose (mg/kg/day)	0	25	75	225	0	25	75	225
Squamous Cell Hyperplasia -Nonglandular Region
Minimal	0	0	1	1	0	0	2	1
Slight	0	0	0	4	0	0	0	4
Moderate	0	0	1	5	0	0	0	5
Total	0	0	2	10	0	0	2	10
Hyperkeratosis – Nonglandular Region
Minimal	0	0	1	1	0	0	2	0
Slight	0	0	1	4	0	0	0	2
Moderate	0	0	0	5	0	0	0	6
Marked	0	0	0	0	0	0	0	1
Total	0	0	2	10	0	0	2	9
Erosion/Ulceration – Nonglandular Region
Minimal	0	0	0	5	0	0	0	4
Slight	0	0	1	1	0	0	0	1
Total	0	0	1	6	0	0	0	5
Submucosal/Mucosal Inflammation – Nonglandular Region
Minimal	0	0	1	2	0	0	1	6
Slight	0	0	0	4	0	0	0	3
Moderate	0	0	0	3	0	0	0	0
Total	0	0	1	9	0	0	1	9
Mucosal Necrosis/Erosion -Glandular Region
Slight	0	0	0	0	0	0	0	2
Moderate	0	0	0	0	0	0	1	1
Total	0	0	0	0	0	0	1	3
Number of tissues examined	5	5	6	10	9	10	10	10

Pancreatic lymph nodes:

Macroscopically enlarged pancreatic lymph nodes in some males treated at 225 mg/kg/day were assessed histologically. In all of them, slightly increased germinal centre development and slight to moderate plasmacytosis were detected.

Summary table of treatment related findings in the pancreatic lymph nodes for animals killed at the end of treatment:

Group/sex	1M	2M	3M	4M	1F	2F	3F	4F
Dose (mg/kg/day)	0	25	75	225	0	25	75	225
Increased Germinal Centre Development
Slight	0	0	0	7	0	0	0	0
Total	0	0	0	7	0	0	0	0
Plasmacytosis
Slight	0	0	0	4	0	0	0	0
Moderate	0	0	0	3	0	0	0	0
Total	0	0	0	7	0	0	0	0
Number of tissues examined	0	0	0	7	0	0	0	0

Applicant's summary and conclusion

Conclusions:

The study was performed according to OECD Guideline with minor deviations, which did not compromise the integrity of the study.

P0 generation: A NOAEL and a LOAEL were established to 25 and 75 mg/kg bw/day, respectively for stomach inflammation observed in both sexes.

F1 generation: The NOAEL of ethoxyethoxyethyl acrylate for reproductive/developmental effects is concluded to be 225 mg/kg/day.

Executive summary:

The study was performed according to OECD Guideline 422 with minor deviations, which did not compromise the integrity of the study.

Three groups of 10 male and 10 female rats received Ethoxy ethoxy ethyl acrylate at doses of 25, 75 and 225 mg/kg/day by oral gavage administration. Males were treated daily for two weeks before pairing, up to necropsy after a minimum of five consecutive weeks. Females were treated daily for two weeks before pairing, throughout pairing, gestation and until Day 13 of lactation

Oral administration of Ethoxy ethoxy ethyl acrylate was well tolerated with no mortalities and no adverse effects of treatment on clinical condition, sensory reactivity, grip strength, motor activity, body weight gain, food intake or blood chemistry measurements in males and females treated with Ethoxy ethoxy ethyl acrylate. Offspring clinical condition, body weight, body weight gain, ano-genital distance and external development were also unaffected by treatment.

Microscopic findings in the stomach of males and females treated at 75 or 225 mg/kg/day are compatible with secondary (reactive) changes due to an irritant effect of the test item on the stomach when administered by oral gavage. Inflammatory lesions were present in the glandular and non-glandular region of the stomach. The inflammatory nature of the lesions affecting both the non-glandular and glandular stomach can compromise the structure and function of the stomach and can thus be considered adverse and potentially relevant to humans.

Macroscopically enlarged local lymph nodes in males treated at 225 mg/kg/day show histological features suggestive of local immunostimulation, which could be secondary to the gastric inflammatory changes.

In addition, an increase in total and differential leucocyte counts were observed only in males treated at 225 mg/kg/day which is likely secondary due to the minimal to moderate inflammatory changes observed at microscopic evaluation in the forestomach of 9/10 males in this group. However a minimal to slight microscopic stomach lesions were observed in 9/10 females at this dose level.

 

Conclusions:

P0 generation: A NOAEL and a LOAEL were established to 25 and 75 mg/kg bw/day, respectively for stomach inflammation observed in both sexes.

F1 generation: The NOAEL of Ethoxy ethoxy ethly acrylate for reproductive/developmental effects is concluded to be 225 mg/kg/day.