5-[(2-hydroxyethyl)amino]-o-cresol

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 17 December 2003 to 03 December 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

22 January 2001

Deviations:

yes

Remarks:

not considered to have compromised the validity or integrity of the study

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

5-[(2-hydroxyethyl)amino]-o-cresol

EC Number:

259-583-7

EC Name:

5-[(2-hydroxyethyl)amino]-o-cresol

Cas Number:

55302-96-0

Molecular formula:

C9H13NO2

IUPAC Name:

5-[(2-hydroxyethyl)amino]-2-methylphenol

Test material form:

solid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Analytical purity: 99.3% (HPLC; Area % without response factor, UV detection)
- Purity test date: August 2004
- Lot/batch No.: 0121442
- Expiration date of the lot/batch: September 2005
- Titre: 99.8% (based upon alkalinity in g/100g)
- Description: beige powder
- Trade name: IMEXINE OAG
- Labeling code: 2948

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at +4°C, protected from light and under nitrogen gas
- Stability under test conditions: test item dosage forms were prepared under nitrogen atmosphere with a frequency depending on their stability (9 days) and were stored at +4°C prior to use, and protected from light (using a glass beaker covered with aluminum foil) and under nitrogen atmosphere until delivery.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Crl CD® (SD) IGS BR, Caesarian Obtained, Barrier Sustained-Virus Antibody Free, (COBS-VAF®).

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories France, L’Arbresle, France.
- Age at study initiation: 10-13 weeks old
- Weight at study initiation (mean body weight): 278 g
- Fasting period before study: no
- Housing: animals were housed in a barriered rodent unit, under specific pathogen free (SPF) standard laboratory conditions. Animals were individually housed in suspended wire-mesh cages (43.0 x 21.5 x 18.0 cm). A
metal tray, containing autoclaved sawdust (SICSA, Alfortville, France), was placed under each cage. The sawdust was changed at least once a week.
The animal room was disinfected before the arrival of the animals and cleaned regularly thereafter.
- Diet: ad libitum to A04 C pelleted maintenance diet (SAFE, Villemoisson, Epinay-sur-Orge, France) distributed weekly
- Water: ad libitum to bottles containing tap water (filtered with a 0.22 μm filter).
The batches of diet and sawdust were analyzed by the suppliers for composition and contaminant levels.
Bacterial and chemical analyses of water are performed regularly by external laboratories, including the detection of possible contaminants (pesticides, heavy metals and nitrosamines).
No contaminants were present in the diet, drinking water or sawdust at levels which may be expected to interfere with or prejudice the outcome of the study.
- Acclimation period: at least 6 days before the beginning of the mating period.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 50 ± 20
- Air changes (per hr): 12 / 12
- Photoperiod (hrs dark / hrs light): 12 cycles/hour of filtered, non-recycled air

The temperature and relative humidity are recorded continuously and the records are checked daily and filed.

IN-LIFE DATES: From: 09 March-25 March 2004 To: 05 april-26 april 2004

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 0.5 % aqueous carboxymethylcellulose

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
- Before preparation, the vehicle was degassed by sonication for at least 15 minutes, then saturated with nitrogen gas, and kept under nitrogen atmosphere for 15 minutes.
- The test item was administered as a suspension in the vehicle: it was ground to a fine powder, using a mortar and pestle, and then mixed with the required quantity of vehicle in order to achieve the required concentrations of 20, 60 and 200 mg/mL.

ADMINISTRATION:
- The oral route was selected to provide an exaggerated model of the normal exposure by cutaneous application in man.
- The dosage forms were administered by gavage using a plastic syringe fitted with a metal gavage tube.
- The quantity of dosage form administered to each animal was adjusted according to the most recently recorded body weight.
- A constant dosage-volume of 5 mL/kg/day was used.
- Vehicle Control animals received the vehicle alone.
- The dosage forms were stirred continuously throughout the dosing procedure.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- A study was performed in the testing laboratory where, the suitability of the proposed formulation procedure and the homogeneity and stability of the test item in the dosage form were checked at concentrations spanning those used in the present study.
- During the treatment period, the concentration of samples taken from each dosage form prepared for use on the first and the last day of treatment was determined, according to the analytical method previously validated in the same testing laboratory.

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1/1
- Length of cohabitation: overnight
- After ... days of unsuccessful pairing replacement of first male by another male with proven fertility.
- Further matings after two unsuccessful attempts: [no / yes (explain)]
- Verification of same strain and source of both sexes: yes; males were from the same strain and the same breeder.
- Proof of pregnancy: sperm in vaginal smear or sperm plug in situ referred to as day 0 post-coitum (p.c.) (checked each morning following mating)

Duration of treatment / exposure:

From day 6 to day 19 post-coitum inclusive.

Frequency of treatment:

Once a day, at approximately the same time

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

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

Doses / concentrations 2

Dose / conc.:

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

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

24 (including the vehicle control group)

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose-levels of this study were selected in agreement with the Sponsor and based on the results of a previous study (1981) performed at 50, 300 and 1800 mg/kg/day, in which a slightly higher pre-implantation loss, correlating with a slightly higher number of corpora lutea, was observed at 1800 mg/kg/day. In the absence of any effect at the lower doses, the dose-levels in this study were set at 100, 300 and 1000 mg/kg/day. The dose-level of 1000 mg/kg/day being the limit dose-level recommended by international guidelines.

- Rationale for animal assignment: before day 3 p.c., the animals were allocated to the groups, according to a stratification procedure based on body weight, recorded on day 0 p.c., to ensure comparatively similar mean body weights among groups. A larger number of animals than necessary was paired to permit selection and/or replacement of individuals before the start of treatment.

- Other: Monitoring of the estrous cycle
During the week of mating, the estrous cycle stage was determined periodically from a fresh vaginal lavage (stained with methylene blue).

- Other: Mating

Examinations

Maternal examinations:

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule:
Morbidity and mortality: Each animal was checked for mortality or signs of morbidity once a day before the treatment period and and at least twice a day during the treatment period. From arrival, the animals were observed at least once a day as part of routine examinations.
Clinical signs: From the start of the treatment period, each animal was observed at least once a day, at approximately the same time for the recording of clinical signs.

BODY WEIGHT: Yes
- Time schedule for examinations: body weight of each female was recorded on days 0, 3, 6, 9, 12, 15, 18 and 20 post-coitum.
- Net body weight (presented as carcass weight): body weight on day 20 minus gravid uterine weight and net body weight change: (body weight on day 20 minus body weight on day 6) minus gravid uterine weight, were calculated for each pregnant female.

FOOD CONSUMPTION: Yes
- The quantity of food consumed by each female was recorded for the following intervals: days 0-3, 3-6, 6-9, 9-12, 12-15, 15-18 and 18-20 post-coitum.

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

SACRIFICE:
- On day 20 post-coitum, all the females were sacrificed by anesthetization with carbon dioxide followed by cervical dislocation.

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on day 20 post-coitum
- Organs examined: principal thoracic and abdominal organs were submitted to a macroscopic post-mortem examination
- A gross evaluation of placentas was also undertaken.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: The weight of the gravid uterus was recorded for each pregnant female (with at least one live fetus).
- Number of corpora lutea,
- Number and distribution of dead and live fetuses,
- Number and distribution of early and late resorptions,
- Number and distribution of uterine scars,
- Number and distribution of implantation sites.

Uterine horns without visible implantation sites were immersed in an aqueous solution of ammonium sulphide (Salewski) to reveal the presence of uterine scars.

The following classification was used to record:
- Uterine scar: uterine implantation without implant,
- Early resorption: evidence of implant without recognizable embryo,
- Late resorption: dead embryo or fetus with external degenerative changes,
- Dead fetus: non live fetus with discernible digits.

Fetal examinations:

The fetal findings were described according to the glossary of the International Federation of Teratology Societies (IFTS) and classified as malformations or variations (Wise, Chahoud):
. malformation refers to a permanent structural change which is likely to adversely affect the survival or health,
. variation refers to a change which occurs within the normal population under investigation and is unlikely to adversely affect survival or health (this might include a delay in growth or morphogenesis which has otherwise followed a normal pattern of development).

- Body weight: recorded for each live fetus
- External examinations: Yes: all per litter (females with at least one live fetus, excluding any autolyzed fetuses). Detailed external examination included the observation of all visible structures, surfaces and orifices. The live fetuses were killed by a subcutaneous injection of thiopental sodium.
- Soft tissue examinations: Yes: half per litter of the live fetuses (fixed with Harrisson’s fluid). A detailed soft tissue examination was performed according to a free-hand serial sectioning technique, which included the observation of all the organs and structures of the head, neck, thorax and abdomen.
- Skeletal examinations: Yes: half per litter of the remaining live fetuses (eviscerated and then fixed with ethyl alcohol). A detailed examination of the skeleton (bone) was performed after staining with alizarin red S. This examination included the observation of all the bone structures of the head, spine, rib cage, pelvis and limbs.
- Sex of the fetuses: determined at the time of evisceration or at the time of the serial sectioning.

Statistics:

- Mean values were compared by one-way analysis of variance and the Dunnett test (mean values being considered as normally distributed and variances being considered as homogeneous).
- Percentage values were compared by the Fisher exact probability test.

Indices:

Pre- and post-implantation loss, fetal or litter incidence and mean proportion of affected fetuses were calculated as follows:

- Pre-implantation loss: [(Number of corpora lutea - Number of implantation sites)/ Number of corpora lutea] X 100
- Post-implantation loss: [(Number of implantation sites - Number of live fetuses)/ Number of implantation sites] X 100
- Fetal or litter incidence: [(Total number of fetuses or litters with a particular finding)/ Total number of fetuses or litters examined] X 100
- Mean proportion of affected fetuses: [(Sum of proportion of fetuses affected in each litter)/ Total number of litters examined] X 100

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

1, 19 and 24 females at 100, 300 and 1000 mg/kg/day, respectively, had brown colored urine, in addition to yellow colored extremities in 6 females at 1000 mg/kg/day. This finding was correlated with the color of the test item and suggested systemic exposure to the test item following oral administration.

Mortality:

no mortality observed

Description (incidence):

No deaths occurred during the study.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Body weights and body weight changes were unaffected by treatment. Net body weight changes (reflecting maternal body weight changes independently of the gravid uterus weight) showed statistical significance when compared to controls. These differences were considered to reflect more the biological variability rather than a treatment-related effect in the absence of a dose-related variation.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

No treatment-related effects were noted in food consumption.

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Description (incidence and severity):

No abnormal necropsy findings were noted at necropsy.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Details on results:

See tables in "Any other information on results incl. Tables"

Maternal developmental toxicity

Number of abortions:

no effects observed

Pre- and post-implantation loss:

no effects observed

Description (incidence and severity):

In the treated groups, the mean number of corpora lutea and implantation sites were similar to the control group values.

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Description (incidence and severity):

The mean number of resorptions (early and late) and dead fetuses was not affected by treatment.

Dead fetuses:

no effects observed

Description (incidence and severity):

The mean number of live fetuses was similar in treated and control groups.

Changes in pregnancy duration:

no effects observed

Description (incidence and severity):

Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): no effects observed

Changes in number of pregnant:

no effects observed

Description (incidence and severity):

23/24, 24/24, 22/24 and 23/24 females in groups control, 100, 300 and 1000 mg/kg/day, respectively, were pregnant with live fetuses at scheduled sacrifice.

Details on maternal toxic effects:

See tables in "Any other information on results incl. Tables"

Effect levels (maternal animals)

Key result

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: No signs of toxicity were noted in the pregnant females

Results (fetuses)

Fetal body weight changes:

no effects observed

Description (incidence and severity):

The fetal body weight was unaffected by treatment.
Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): no effects observed

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Description (incidence and severity):

The percentage of male fetuses was similar among the groups.

Changes in litter size and weights:

no effects observed

External malformations:

no effects observed

Description (incidence and severity):

No abnormal external fetal observations were noted in any group.

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

- No malformations were considered to be treatment-related as missing lumbar vertebra was the only malformation. This was noted in a single fetus at 1000 mg/kg/day and can be seen spontaneously in control fetuses.
- No findings were indicative of any treatment-related effect and the general ossification of fetuses was not affected by the treatment.

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

- No malformations were considered to be treatment-related as they were limited to one fetus from the 300 and one from the 1000 mg/kg/day groups. They were therefore considered to be spontaneous in origin.
- No variations were considered to be treatment-related. All variations were considered to be evenly distributed between the groups, including the control group, with no dose-related increase, or limited to one single fetus per group.

Other effects:

no effects observed

Details on embryotoxic / teratogenic effects:

See tables in "Any other information on results incl. Tables"

Effect levels (fetuses)

Key result

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No signs of toxicity noted on the embryofetal development or on the growth in utero at any dose-level.

Overall developmental toxicity

Key result

Developmental effects observed:

no

Any other information on results incl. tables

CHEMICAL ANALYSIS OF THE DOSAGE FORMS:

- Throughout the study, a satisfactory agreement was observed between the nominal and actual concentrations of the test item in the administered dosage forms as the deviations from nominal concentration were in an acceptable range of ± 10% (maximal deviation: -6%).

Table 1: CLINICAL SIGNS (Summary table/Females/Pregnancy period)

 

Dose:(mg/kg/day)            0            100              300             1000

Mortality

FINALSACRIFICE                            24               24               24              24

Secretion/Excretion

CHROMODACRYORRHEA	0	1	0	0
BROWN COLOURED URINE	0	1	19	24

Coloration

YELLOWCOLOUREDEXTREMITIES                 0             0             0             6

 

Normal

NOREMARKABLEOBSERVATIONS                  24               22                5             0

 

Table 2: BODY WEIGHT (Mean values/grams/Females/Pregnancy period)

 

Dose:(mg/kg/day)            0            100              300                           1000

DAY0	MEAN	238 d	237	233	236
	S.D.	15	15	15	14
	N	23	24	22	23
DAY3	MEAN	258 d	258	256	257
	S.D.	14	15	14	14
	N	23	24	22	23
DAY6	MEAN	279 d	277	276	279
	S.D.	13	14	14	15
	N	23	24	22	23
DAY9	MEAN	293 d	286	285	286
	S.D.	17	15	13	13
	N	23	24	22	23
DAY 12	MEAN	309 d	299	300	300
	S.D.	17	16	16	15
	N	23	24	22	23
DAY 15	MEAN	331 d	320	318	323
	S.D.	18	17	17	17
	N	23	24	22	23
DAY 18	MEAN	366 d	357	352	360
	S.D.	22	19	21	20
	N	23	24	22	23
DAY 20	MEAN	400 d	384	380	390
	S.D.	28	22	27	25
	N	23	24	22	23

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

Statistical key:d=ANOVA+Dunnett-test

 

 

 

Table 3:BODY WEIGHT CHANGE (Mean values/grams/Females/Pregnancy period)

 

Dose:(mg/kg/day)            0            100              300             1000

 

DAYS 0 TO 3	MEAN	20 d	21	23	21
	S.D.	5	4	6	5
	N	23	24	22	23
mean percent change	MEAN%	8.6	8.7	9.8	8.8
DAYS 3 TO 6	MEAN	21 d	20	20	22
	S.D.	5	6	5	5
	N	23	24	22	23
mean percent change	MEAN%	8.0	7.7	7.8	8.4
DAYS 6 TO 9	MEAN	14 d	9	9	8
	S.D.	8	8	10	10
	N	23	24	22	23
mean percent change	MEAN%	4.9	3.2	3.4	2.9
DAYS 9 TO 12	MEAN	16 d	13	15	14
	S.D.	8	9	9	8
	N	23	24	22	23
mean percent change	MEAN%	5.4	4.7	5.2	4.9
DAYS 12 TO 15	MEAN	22 d	21	18	23
	S.D.	7	10	6	8
	N	23	24	22	23
mean percent change	MEAN%	7.3	7.2	6.1	7.5
DAYS 15 TO 18	MEAN	35 d	36	34	37
	S.D.	8	10	14	11
	N	23	24	22	23
mean percent change	MEAN%	10.6	11.3	10.6	11.6
DAYS 18 TO 20	MEAN	34 d	28	28	30
	S.D.	10	8	8	8
	N	23	24	22	23
mean percent change	MEAN%	9.2	7.8	7.9	8.2
DAYS 6 TO 20	MEAN	121 d	107	104*	111
	S.D.	21	16	26	19
	N	23	24	22	23
mean percentchange	MEAN%	43.3	38.8	37.8	40.1

Statistical key:d=ANOVA+Dunnett-test     *=p<0.05

Table 4: NET BODY WEIGHT CHANGE (Mean values/grams/Females/Pregnancy period)

 

Dose:(mg/kg/day)            0            100              300             1000

GRAVID UTERUS	MEAN	81.7 d	82.9	73.9	83.3
	S.D.	17.1	9.4	22.8	10.3
	N	23	24	22	23
CARCASS	MEAN	318.2 d	301.6**	305.7	306.9
	S.D.	15.0	17.0	18.2	21.6
	N	23	24	22	23
NET WEIGHT CHANGE FROM DAY 6	MEAN	39.1 d	24.3**	29.9	28.1*
	S.D.	12.0	11.8	12.3	18.1
	N	23	24	22	23

Statistical key:d=ANOVA+Dunnett-test         *=p<0.05 **=p<0.01

 CARCASS WEIGHT = TERMINAL BODY WEIGHT MINUS UTERINE WEIGHT

NET WEIGHT CHANGE FROM DAY 6 = CARCASS WEIGHT MINUS DAY 6 BODY WEIGHT

 

Table 5: FOOD CONSUMPTION (Mean values/grams per day/Females/Pregnancy period)

 

Dose:(mg/kg/day)            0            100              300             1000

 

DAYS	0 to	3	MEAN	23 d	23	23	23
			S.D.	2	2	2	2
			N	23	24	22	23
DAYS	3TO	6	MEAN	25 d	26	27	26
			S.D.	2	2	3	2
			N	23	24	22	23
DAYS	6 TO	9	MEAN	26 d	25	25	24
			S.D.	2	3	4	4
			N	23	24	22	23
DAYS	9TO	12	MEAN	25 d	25	25	25
			S.D.	6	5	5	5
			N	23	24	22	23
DAYS 12 TO 15			MEAN	28 d	27	26	29
			S.D.	6	3	3	7
			N	23	24	22	23
DAYS 15 TO 18			MEAN	28 d	28	28	29
			S.D.	2	3	3	3
			N	23	24	22	23
DAYS 18 TO 20			MEAN	28 d	25	26	26
			S.D.	3	4	4	5
			N	23	24	22	23

Statistical key:d=ANOVA+Dunnett-test

 

Table 6: HYSTERECTOMY DATA (Summary table)

Dose:(mg/kg/day)            0            100              300             1000

PregnantFemalesAliveatTerm	N	23	24	22	23
withTotalResorptions	N	0	0	0	0
withallDeadFetuses	N	0	0	0	0
with LiveFetuses	N	23	24	22	23
Corpora Lutea	TOTAL	361	380	327	373
No. per animal	MEAN	15.7 d	15.8	14.9	16.2
	S.D.	2.2	2.1	4.2	2.2
Implantation Sites	TOTAL	335	350	296	351
No. per animal	MEAN	14.6 d	14.6	13.5	15.3
	S.D.	2.9	1.9	4.2	2.1
Preimplantation Loss	TOTAL	26 f	30	31	22
	%	7.2	7.9	9.5	5.9
Fetuses	N	328	338	281	335
No. per animal	MEAN	14.3 d	14.1	12.8	14.6
	S.D.	3.0	1.9	4.1	2.3
Alive	%	100.0	100.0	100.0	100.0
Dead	%	0.0	0.0	0.0	0.0
Live Fetuses	N	328 f	338	281	335
%of implantation sites		97.9	96.6	94.9	95.4
No. per animal	MEAN	14.3 d	14.1	12.8	14.6
	S.D.	3.0	1.9	4.1	2.3
Dead Fetuses	N	0 f	0	0	0
%of implantation sites		0.0	0.0	0.0	0.0
No. per animal	MEAN	0.0	0.0	0.0	0.0
	S.D.	0.0	0.0	0.0	0.0

 

Resorptions+Scars	N	7 f	12	15	16
%of implantation sites		2.1	3.4	5.1	4.6
No. per animal	MEAN	0.3 d	0.5	0.7	0.7
	S.D.	0.6	0.7	1.1	1.0
Implant Scars	N	0 f	0	0	0
%of implantation sites		0.0	0.0	0.0	0.0
No. per animal	MEAN	0.0	0.0	0.0	0.0
	S.D.	0.0	0.0	0.0	0.0
Resorptions: early	N	6 f	11	11	14
%of implantation sites		1.8	3.1	3.7	4.0
No. per animal	MEAN	0.3 d	0.5	0.5	0.6
	S.D.	0.5	0.6	1.1	0.9
Resorptions: late	N	1 f	1	4	2
%of implantation sites		0.3	0.3	1.4	0.6
No. per animal	MEAN	0.0 d	0.0	0.2	0.1
	S.D.	0.2	0.2	0.4	0.4
PostimplantationLoss	TOTAL	7 f	12	15	16
%of implantation sites		2.1	3.4	5.1	4.6
No. per animal	MEAN	0.3 d	0.5	0.7	0.7
	S.D.	0.6	0.7	1.1	1.0
Male Fetuses	N	166 f	176	135	163
	%	50.6	52.1	48.0	48.7
Female Fetuses	N	162 f	162	146	172
	%	49.4	47.9	52.0	51.3
Fetal Body Weight (g)	MEAN	3.58 d	3.67	3.61	3.53
	S.D.	0.27	0.25	0.23	0.23
Male Fetuses	MEAN	3.66 d	3.76	3.67	3.61
	S.D.	0.27	0.25	0.26	0.27
Female Fetuses	MEAN	3.48 d	3.56	3.53	3.47
	S.D.	0.24	0.25	0.23	0.24

Statistical key: d=ANOVA+Dunnett-test f=Fisher sexact test

 

Table 7: SUMMARY OF FETAL EXTERNAL MALFORMATIONS

 

Dose:(mg/kg/day)            0            100              300             1000

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	328	338	281	335
Live	N	328	338	281	335
Dead	N	0	0	0	0
TOTAL FETAL EXTERNAL MALFORMATIONS
Fetal Incidence	N	0 f	0	0	0
	%	0.0	0.0	0.0	0.0
Litter Incidence	N	0 f	0	0	0
	%	0.0	0.0	0.0	0.0
AffectedFetuses/Litter	MEAN%	0.0	0.0	0.0	0.0
	S.D.	0.0	0.0	0.0	0.0

Statistical key:f=Fishers exact test

 

Table 8:SUMMARY OF FETAL EXTERNAL VARIATIONS

 

Dose:(mg/kg/day)            0            100              300             1000

Litters Evaluated	N		23	24	22	23
Fetuses Evaluated	N		328	338	281	335
Live	N		328	338	281	335
Dead	N		0	0	0	0
TOTAL FETALEXTERNAL Fetal Incidence	VARIATIONS N		0 f	0	0	0
	%		0.0	0.0	0.0	0.0
LitterIncidence	N		0 f	0	0	0
	%		0.0	0.0	0.0	0.0
AffectedFetuses/Litter		MEAN%	0.0	0.0	0.0	0.0
		S.D.	0.0	0.0	0.0	0.0

Statistical key:  f=Fishers exact te 

 

Table 9: SUMMARY OF FETAL SOFT TISSUE MALFORMATIONS

Dose:(mg/kg/day)            0            100              300             1000

Litters Evaluated	N	23	24	21	23
Fetuses Evaluated	N	158	164	137	162
HEART ------ Litter Incidence	N	0	0	1	0
Fetal Incidence	N	0	0	1	0
VENTRICULARSEPTUMDEFECT Fetal Incidence	N	0 f	0	1	0
	%	0.0	0.0	0.7	0.0
Litter Incidence	N	0 f	0	1	0
	%	0.0	0.0	4.8	0.0
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.7	0.0
	S.D.	0.0	0.0	3.1	0.0

 

GONADS ------- Litter Incidence	N	0	0	0	1
Fetal Incidence	N	0	0	0	1
SUPERNUMERARY GONAD Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.5
	S.D.	0.0	0.0	0.0	2.3

 

TOTALFETALSOFTTISSUEMALFORMATIONS

Fetal Incidence N 0 f 0 1 1   % 0.0 0.0 0.7 0.6 Litter Incidence N 0 f 0 1 1   % 0.0 0.0 4.8 4.3 AffectedFetuses/Litter MEAN% 0.0 d 0.0 0.7 0.5   S.D. 0.0 0.0 3.1 2.3

Statistical key:   d=ANOVA+Dunnett-test     f=Fishers exact test

 

Table 10: SUMMARY OF FETAL SOFT TISSUE VARIATIONS

Dose:(mg/kg/day)            0            100              300             1000

Litters Evaluated	N	23	24	21	23
Fetuses Evaluated	N	158	164	137	162
HEART ------ Litter Incidence	N	0	0	1	0
Fetal Incidence	N	0	0	1	0
ENLARGEDATRIALCHAMBER Fetal Incidence	N	0 f	0	1	0
	%	0.0	0.0	0.7	0.0
Litter Incidence	N	0 f	0	1	0
	%	0.0	0.0	4.8	0.0
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.7	0.0
	S.D.	0.0	0.0	3.1	0.0

 

LUNGS ------ Litter Incidence	N	0	0	1	0
Fetal Incidence	N	0	0	1	0
LUNG:DILATEDBRONCHI Fetal Incidence	N	0 f	0	1	0
	%	0.0	0.0	0.7	0.0
Litter Incidence	N	0 f	0	1	0
	%	0.0	0.0	4.8	0.0
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.8	0.0
	S.D.	0.0	0.0	3.6	0.0

 

KIDNEYS
--------
Litter Incidence	N	3	4	4	1
Fetal Incidence	N	3	6	5	2

 

Litters Evaluated	N	23	24	21	23
Fetuses Evaluated	N	158	164	137	162
DILATEDRENALPELVIS Fetal Incidence	N	3 f	6	5	2
	%	1.9	3.7	3.6	1.2
Litter Incidence	N	3 f	4	4	1
	%	13.0	16.7	19.0	4.3
AffectedFetuses/Litter	MEAN%	1.6 d	3.5	3.3	1.4
	S.D.	4.3	9.6	7.6	7.0

 

URETER ------- Litter Incidence	N	2	3	2	0
Fetal Incidence	N	2	3	3	0
DILATED URETER Fetal Incidence	N	2 f	3	3	0
	%	1.3	1.8	2.2	0.0
Litter Incidence	N	2 f	3	2	0
	%	8.7	12.5	9.5	0.0
AffectedFetuses/Litter	MEAN%	1.2 d	1.8	2.0	0.0
	S.D.	3.9	4.8	6.8	0.0

 

GENERAL -------- LitterIncidence         N	1	3	1	1
FetalIncidence          N	2	4	1	1
ABDOMINAL CAVITY: HEMORRHAGE FetalIncidence          N	2 f	0	0	0
%	1.3	0.0	0.0	0.0
LitterIncidence         N	1 f	0	0	0
%	4.3	0.0	0.0	0.0
AffectedFetuses/Litter    MEAN%	1.2 d	0.0	0.0	0.0
S.D.	6.0	0.0	0.0	0.0

 

Litters Evaluated	N	23	24	21	23
Fetuses Evaluated	N	158	164	137	162
THORACIC CAVITY:HEMORRHAGE Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.7
	S.D.	0.0	0.0	0.0	3.5
HEMATOMA Fetal Incidence	N	0 f	4	1	0
	%	0.0	2.4	0.7	0.0
Litter Incidence	N	0 f	3	1	0
	%	0.0	12.5	4.8	0.0
AffectedFetuses/Litter	MEAN%	0.0 d	2.0	0.6	0.0
	S.D.	0.0	5.7	2.7	0.0
TOTAL FETALSOFTTISSUEVARIATIONS
Fetal Incidence	N	6 f	12	8	3
	%	3.8	7.3	5.8	1.9
Litter Incidence	N	4 f	7	6	2
	%	17.4	29.2	28.6	8.7
AffectedFetuses/Litter	MEAN%	3.5 d	6.7	5.4	2.2
	S.D.	9.6	12.9	9.3	7.6

Statistical key:d=ANOVA+Dunnett-test     f=Fishers exact test

Table 11: SUMMARY OF FETAL SKELETAL MALFORMATIONS

Dose:(mg/kg/day)            0            100              300             1000

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
LUMBAR VERT. ------------- Litter Incidence	N	0	0	0	1
Fetal Incidence	N	0	0	0	1
ABSENT LUMBARVERTEBRA(E) Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.6
	S.D.	0.0	0.0	0.0	3.0
TOTAL FETAL SKELETAL MALFORMATIONS
Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.6
	S.D.	0.0	0.0	0.0	3.0

Statistical key:d=ANOVA+Dunnett-test     f=Fishers exact test

 

Table 12: SUMMARY OF FETAL SKELETAL VARIATIONS

Dose:(mg/kg/day)            0            100              300             1000

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
HEAD-SKULL ----------- Litter Incidence	N	9	10	7	7
Fetal Incidence	N	19	13	20	21
INCOMPLETEOSSIFICATIONOFINTERPARIETAL
Fetal Incidence	N	18 f	10	18	20
	%	10.6	5.7	12.5	11.6
Litter Incidence	N	8 f	7	7	7
	%	34.8	29.2	31.8
AffectedFetuses/Litter	MEAN%	10.1 d	5.8	12.2	11.5
	S.D.	16.8	10.2	20.8	21.0
INCOMPLETEOSSIFICATIONOFFRONTAL
Fetal Incidence	N	3 f	1	2	1
	%	1.8	0.6	1.4	0.6
Litter Incidence	N	3 f	1	1	1
	%	13.0	4.2	4.5	4.3
AffectedFetuses/Litter	MEAN%	1.6 d	0.7	1.8	0.6
	S.D.	4.4	3.4	8.5	3.0
INCOMPLETEOSSIFICATIONOFPARIETAL
Fetal Incidence	N	5 f	3	7	6
	%	2.9	1.7	4.9	3.5
Litter Incidence	N	3 f	3	4	5
	%	13.0	12.5	18.2	21.7
AffectedFetuses/Litter	MEAN%	3.0 d	2.0	5.2	3.5
	S.D.	9.5	5.6	14.1	7.4
Dose:(mg/kg/day)   0            100              300             1000 Litters Evaluated N 23 24 22 23 Fetuses Evaluated N 170 174 144 173   INCOMPLETEOSSIFICATIONOFSUPRAOCCIPITAL Fetal Incidence N 7 f 2 6 5   % 4.1 1.1 4.2 2.9 Litter Incidence N 5 f 2 3 4   % 21.7 8.3 13.6 17.4 AffectedFetuses/Litter MEAN% 4.1 d 1.1 4.2 3.0   S.D. 9.8 3.8 12.9 7.2   INCOMPLETEOSSIFICATIONOFNASAL Fetal Incidence N 0 f 0 1 2   % 0.0 0.0 0.7 1.2 Litter Incidence N 0 f 0 1 2   % 0.0 0.0 4.5 8.7 AffectedFetuses/Litter MEAN% 0.0 d 0.0 0.9 1.1   S.D. 0.0 0.0 4.3 3.7 ENLARGED FONTANEL Fetal Incidence   N   0 f   0   0   1   % 0.0 0.0 0.0 0.6 Litter Incidence N 0 f 0 0 1   % 0.0 0.0 0.0 4.3 AffectedFetuses/Litter MEAN% 0.0 d 0.0 0.0 0.5   S.D. 0.0 0.0 0.0 2.3   HEAD-OTHERS   ------------ Litter Incidence N 9 12 6 8 Fetal Incidence N 21 20 10 14

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
INCOMPLETEOSSIFICATIONOFSUPRAOCCIPITAL
Fetal Incidence	N	7 f	2	6	5
	%	4.1	1.1	4.2	2.9
Litter Incidence	N	5 f	2	3	4
	%	21.7	8.3	13.6	17.4
AffectedFetuses/Litter	MEAN%	4.1 d	1.1	4.2	3.0
	S.D.	9.8	3.8	12.9	7.2
INCOMPLETEOSSIFICATIONOFNASAL
Fetal Incidence	N	0 f	0	1	2
	%	0.0	0.0	0.7	1.2
Litter Incidence	N	0 f	0	1	2
	%	0.0	0.0	4.5	8.7
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.9	1.1
	S.D.	0.0	0.0	4.3	3.7
ENLARGED FONTANEL Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.5
	S.D.	0.0	0.0	0.0	2.3

 

HEAD-OTHERS
------------
Litter Incidence	N	9	12	6	8
Fetal Incidence	N	21	20	10	14

 

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
INCOMPLETEOSSIFICATIONOFHYOID
Fetal Incidence	N	9 f	11	4	5
	%	5.3	6.3	2.8	2.9
Litter Incidence	N	6 f	6	2	5
	%	26.1	25.0	9.1	21.7
AffectedFetuses/Litter	MEAN%	5.1 d	5.9	2.3	2.7
	S.D.	10.5	12.0	8.3	5.3
UNOSSIFIED HYOID Fetal Incidence	N	12 f	9	6	9
	%	7.1	5.2	4.2	5.2
Litter Incidence	N	6 f	7	4	6
	%	26.1	29.2	18.2	26.1
AffectedFetuses/Litter	MEAN%	6.8 d	5.4	4.3	5.2
	S.D.	15.1	9.4	10.5	10.7

 

THORACIC VERT. --------------- Litter Incidence	N	8	7	7	11
Fetal Incidence	N	16	11	13	14
THORACIC VERTEBRA(E): INCOMPLETE OSSIFICATION OF CENTRUM
Fetal Incidence	N	15 f	10	12	11
	%	8.8	5.7	8.3	6.4
Litter Incidence	N	7 f	6	7	10
	%	30.4	25.0	31.8	43.5
AffectedFetuses/Litter	MEAN%	8.2 d	5.7	8.0	6.3
	S.D.	15.7	11.3	15.2	8.1

 

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
THORACICVERTEBRA(E):UNOSSIFIEDCENTRUM
Fetal Incidence	N	2 f	1	1	1
	%	1.2	0.6	0.7	0.6
Litter Incidence	N	2 f	1	1	1
	%	8.7	4.2	4.5	4.3
AffectedFetuses/Litter	MEAN%	1.3 d	0.6	0.6	0.6
	S.D.	4.2	2.9	3.0	3.0
THORACIC VERTEBRA(E): BIPARTITE OSSIFICATION OF CENTRUM
Fetal Incidence	N	1 f	1	2	3
	%	0.6	0.6	1.4	1.7
Litter Incidence	N	1 f	1	2	3
	%	4.3	4.2	9.1	13.0
AffectedFetuses/Litter	MEAN%	0.6 d	0.6	1.1	1.7
	S.D.	3.0	2.9	3.5	4.6

 

SACRAL VERT. ------------- Litter Incidence	N	4	2	4	5
Fetal Incidence	N	7	3	5	7
SACRAL VERTEBRA(E): INCOMPLETE OSSIFICATION OF ARCH
Fetal Incidence	N	7 f	3	5	7
	%	4.1	1.7	3.5	4.0
Litter Incidence	N	4 f	2	4	5
	%	17.4	8.3	18.2	21.7
AffectedFetuses/Litter	MEAN%	4.2 d	1.6	3.8	3.9
	S.D.	10.6	5.8	8.9	8.2

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
CAUDAL VERT. ------------- Litter Incidence	N	5	4	6	6
Fetal Incidence	N	8	11	12	14
CAUDAL VERTEBRA(E): INCOMPLETE OSSIFICATION OF CENTRUM
FetalIncidence          N		6 f	11	10	13
%		3.5	6.3	6.9	7.5
LitterIncidence         N		5 f	4	4	6
%		21.7	16.7	18.2	26.1
AffectedFetuses/Litter    MEAN%		3.3 d	5.9	7.2	6.4
S.D.		6.6	18.6	19.6	13.6
UNOSSIFIED CAUDAL VERTEBRA(E) FetalIncidence          N		0 f	0	1	0
%		0.0	0.0	0.7	0.0
LitterIncidence         N		0 f	0	1	0
%		0.0	0.0	4.5	0.0
AffectedFetuses/Litter    MEAN%		0.0 d	0.0	0.6	0.0
S.D.		0.0	0.0	3.0	0.0
CAUDALVERTEBRA(E):UNOSSIFIEDCENTRUM
Fetal Incidence	N	2 f	1	2	4
	%	1.2	0.6	1.4	2.3
Litter Incidence	N	1 f	1	2	3
	%	4.3	4.2	9.1	13.0
AffectedFetuses/Litter	MEAN%	1.2 d	0.5	1.3	1.9
	S.D.	6.0	2.6	4.2	5.5

 

LittersEvaluated          N            23                24                22               23

FetusesEvaluated          N           170               174               144               173

STERNEBRA

----------

LitterIncidence         N              23               24                22               23

FetalIncidence          N            168              170               139              169

UNOSSIFIED 5th STERNEBRA

FetalIncidence          N             61f            42               47               61

%          35.9              24.1             32.6             35.3

Litter Incidence	N	19 f	19	16	15
	%	82.6	79.2	72.7	65.2
AffectedFetuses/Litter	MEAN%	34.0 d	23.5	31.4	33.9
	S.D.	26.0	24.1	30.8	30.9
UNOSSIFIED6thSTERNEBRA Fetal Incidence	N	7 f	8	9	9
	%	4.1	4.6	6.3	5.2
Litter Incidence	N	5 f	4	6	4
	%	21.7	16.7	27.3	17.4
AffectedFetuses/Litter	MEAN%	4.1 d	4.4	5.5	4.7
	S.D.	9.0	13.3	10.8	11.8
INCOMPLETE OSSIFICATION OF 1st TO 4th STERNEBRA(E)
Fetal Incidence	N	85 f	73	50	77
	%	50.0	42.0	34.7	44.5
Litter Incidence	N	20 f	23	17	20
	%	87.0	95.8	77.3	87.0
AffectedFetuses/Litter	MEAN%	50.8 d	42.1	31.8	43.8
	S.D.	37.8	28.4	27.1	32.8

 

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
INCOMPLETE OSSIFICATION OF 5th STERNEBRA
Fetal Incidence	N	105 f	127*	92	104
	%	61.8	73.0	63.9	60.1
Litter Incidence	N	22 f	24	22	23
	%	95.7	100.0	100.0	100.0
AffectedFetuses/Litter	MEAN%	63.6 d	73.8	65.3	61.8
	S.D.	24.6	22.8	28.0	29.4
INCOMPLETE OSSIFICATION OF 6th STERNEBRA
Fetal Incidence	N	144 f	121	107	141
	%	84.7	69.5	74.3	81.5
Litter Incidence	N	23 f	23	21	23
	%	100.0	95.8	95.5	100.0
AffectedFetuses/Litter	MEAN%	84.7 d	69.5	73.0	81.4
	S.D.	16.7	29.8	25.2	19.9
UNOSSIFIED 1st TO 4th STERNEBRA(E)
Fetal Incidence	N	0 f	2	1	0
	%	0.0	1.1	0.7	0.0
Litter Incidence	N	0 f	1	1	0
	%	0.0	4.2	4.5	0.0
AffectedFetuses/Litter	MEAN%	0.0 d	1.0	0.6	0.0
	S.D.	0.0	5.1	3.0	0.0

 

RIB
----
Litter Incidence	N	3	4	9	5
Fetal Incidence	N	4	4	10	7

 

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
SHORT RIB(S) Fetal Incidence	N	4 f	1	5	5
	%	2.4	0.6	3.5	2.9
Litter Incidence	N	3 f	1	5	3
	%	13.0	4.2	22.7	13.0
AffectedFetuses/Litter	MEAN%	2.3 d	0.6	3.2	3.0
	S.D.	6.8	2.9	6.1	9.4
SHORT SUPERNUMERARY 14th RIB(S)
Fetal Incidence	N	0 f	3	3	1
	%	0.0	1.7	2.1	0.6
Litter Incidence	N	0 f	3	2	1
	%	0.0	12.5	9.1	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	1.7	1.8	0.6
	S.D.	0.0	4.5	6.0	3.0
UNOSSIFIED RIB(S) Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.6
	S.D.	0.0	0.0	0.0	3.0
INCOMPLETEOSSIFICATIONOFRIB(S)
Fetal Incidence	N	1 f	0	1	0
	%	0.6	0.0	0.7	0.0
Litter Incidence	N	1 f	0	1	0
	%	4.3	0.0	4.5	0.0
AffectedFetuses/Litter	MEAN%	0.6 d	0.0	0.8	0.0
	S.D.	3.0	0.0	3.6	0.0

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
WAVY RIB(S) Fetal Incidence	N	1 f	0	1	1
	%	0.6	0.0	0.7	0.6
Litter Incidence	N	1 f	0	1	1
	%	4.3	0.0	4.5	4.3
AffectedFetuses/Litter	MEAN%	0.6 d	0.0	0.9	0.6
	S.D.	3.0	0.0	4.3	3.0
THICKENED RIB(S) Fetal Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	0.6
Litter Incidence	N	0 f	0	0	1
	%	0.0	0.0	0.0	4.3
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.0	0.6
	S.D.	0.0	0.0	0.0	3.0

 

METACARPAL BONE ---------------- LitterIncidence         N	8	5	8	12
FetalIncidence          N	17	14	18	19
UNOSSIFIED 4th METACARPAL(S) FetalIncidence          N	17 f	14	16	19
%	10.0	8.0	11.1	11.0
LitterIncidence         N	8 f	5	6	12
%	34.8	20.8	27.3	52.2
AffectedFetuses/Litter    MEAN%	9.7 d	7.4	9.2	10.7
S.D.	17.6	18.0	20.5	14.4

 

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
INCOMPLETE OSSIFICATION OF 1st TO 3rd METACARPALS
Fetal Incidence	N	1 f	0	3	2
	%	0.6	0.0	2.1	1.2
Litter Incidence	N	1 f	0	3	2
	%	4.3	0.0	13.6	8.7
AffectedFetuses/Litter	MEAN%	0.5 d	0.0	2.1	1.1
	S.D.	2.3	0.0	5.3	3.7

 

METATARSAL BONE ---------------- Litter Incidence	N	2	0	2	1
Fetal Incidence	N	4	0	3	1
INCOMPLETEOSSIFICATIONOFMETATARSAL(S)
Fetal Incidence	N	4 f	0	3	1
	%	2.4	0.0	2.1	0.6
Litter Incidence	N	2 f	0	2	1
	%	8.7	0.0	9.1	4.3
AffectedFetuses/Litter	MEAN%	2.0 d	0.0	2.2	0.6
	S.D.	7.3	0.0	7.6	3.0
UNOSSIFIEDMETATARSAL(S) Fetal Incidence	N	0 f	0	1	0
	%	0.0	0.0	0.7	0.0
Litter Incidence	N	0 f	0	1	0
	%	0.0	0.0	4.5	0.0
AffectedFetuses/Litter	MEAN%	0.0 d	0.0	0.6	0.0
	S.D.	0.0	0.0	3.0	0.0

 

Litters Evaluated	N	23	24	22	23
Fetuses Evaluated	N	170	174	144	173
PELVIS ------- Litter Incidence	N	8	4	3	6
Fetal Incidence	N	16	6	3	11
INCOMPLETEOSSIFICATIONOFPUBIS
Fetal Incidence	N	16 f	6	3	11
	%	9.4	3.4	2.1	6.4
Litter Incidence	N	8 f	4	3	6
	%	34.8	16.7	13.6	26.1
AffectedFetuses/Litter	MEAN%	12.9 d	3.4	2.3	6.3
	S.D.	25.5	8.3	6.0	12.4
INCOMPLETEOSSIFICATIONOFILIUM
Fetal Incidence	N	1 f	0	0	0
	%	0.6	0.0	0.0	0.0
Litter Incidence	N	1 f	0	0	0
	%	4.3	0.0	0.0	0.0
AffectedFetuses/Litter	MEAN%	0.6 d	0.0	0.0	0.0
	S.D.	3.0	0.0	0.0	0.0
INCOMPLETEOSSIFICATIONOFISCHIUM
Fetal Incidence	N	1 f	1	0	2
	%	0.6	0.6	0.0	1.2
Litter Incidence	N	1 f	1	0	2
	%	4.3	4.2	0.0	8.7
AffectedFetuses/Litter	MEAN%	0.6 d	0.5	0.0	1.2
	S.D.	3.0	2.6	0.0	4.1

 

LittersEvaluated	N	23	24	22	23
FetusesEvaluated	N	170	174	144	173
SPINE ------ Litter Incidence	N	0	0	0	1
Fetal Incidence	N	0	0	0	1
PRESENCE OF 25 PRE-SACRAL VERTEBRAE
FetalIncidence          N		0 f	0	0	1
%		0.0	0.0	0.0	0.6
LitterIncidence         N		0 f	0	0	1
%		0.0	0.0	0.0	4.3
AffectedFetuses/Litter    MEAN%		0.0 d	0.0	0.0	0.6
S.D.		0.0	0.0	0.0	3.0
TOTAL FETAL SKELETAL VARIATIONS FetalIncidence          N		169 f	172	141	170
%		99.4	98.9	97.9	98.3
LitterIncidence         N		23 f	24	22	23
%		100.0	100.0	100.0	100.0
Affected Fetuses/Litter    MEAN%		99.4 d	99.0	97.9	98.3
S.D.		3.0	5.1	5.3	4.5

Statistical key:   d=ANOVA+Dunnett-test     f=Fishers exact test

 

 

Applicant's summary and conclusion

Conclusions:

The test item, 2-methyl-5-hydroxyethylamino-phenol, administered daily by gavage to pregnant female Sprague-Dawley rats, from day 6 to 19 p.c., was well tolerated at 100, 300 and 1000 mg/kg/day. No signs of toxicity were noted in the pregnant females, on the embryofetal development or on the growth in utero at any dose-level.
Therefore, under the experimental conditions of this study, the No Observed Adverse Effect Level (NOAEL) for maternal toxicity and for embryofetal development were both considered to be 1000 mg/kg/day.

Executive summary:

This GLP-compliant study was performed to assess the potential toxic effects of 2-Methyl-5-hydroxyethylaminophenol on the pregnant female and on embryonic and fetal development, following daily oral administration to pregnant female rats, from implantation to one day before the scheduled hysterectomy (day 6 to day 19 post-coitum (p.c.) inclusive)., according to OECD Guideline 414 (Prenatal Development Toxicity Study) (dated 22th January 2001).

Material and methods

The test material diluted in 0.5 % carboxymethylcellulose in water was administered to 24 mated female rats per dose group by gavage at the doses 100, 300 and 1000 mg/kg bw from day 6 to 19 of gestation, the control group received the vehicle only.

The animals were observed daily for clinical signs. Individual body weights were recorded at days 0, 3, 6, 9, 12, 15, 18 and 20 p.c. Food consumption was measured for the day intervals 0-3, 3-6, 6-9, 9-12, 12-15, 15-18 and 18-20 p.c. All mated females were sacrificed at day 20 of gestation. Immediately following sacrifice, the uterus was removed, weighed and the number of (non)viable foetuses, early and late resorptions and the number of total implantations and corpora lutea was recorded. A macroscopic examination of the organs was carried out. All foetuses were individually weighed and the sex of the foetuses was determined. One half of the foetuses was examined for skeletal defects and variations of the ossification process by Alizarin Red staining and one half was evaluated for visceral imperfections (organic defects).

Results

No deaths occurred during the study. No treatment-related clinical signs were observed except urine coloration, affecting 1, 19 and 24 females at 100, 300 and 1000 mg/kg/day respectively.

This observation was related to the color of the test item and suggested systemic exposure to the test item following oral administration. Body weight, body weight gain and food consumption were unaffected by the treatment. No necropsy findings were observed in the dams.

None of the litter parameters were affected by treatment with the test item.

The number of malformations and the different variations were not indicative of any treatment-related effect and the general ossification of fetuses was unaffected by treatment.

Conclusion

The test item, 2-methyl-5-hydroxyethylamino-phenol, administered daily by gavage to pregnant female Sprague-Dawley rats, from day 6 to 19 p.c., was well tolerated at 100, 300 and 1000 mg/kg/day. No signs of toxicity were noted in the pregnant females, on the embryofetal development or on the growth in utero at any dose-level.

Therefore, under the experimental conditions of this study, the No Observed Adverse Effect Level (NOAEL) for maternal toxicity and for embryofetal development were both considered to be 1000 mg/kg/day.