Biphenyl-4,4'-diol

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted in accordance with OECD Test guideline No 422 and with the principles of GLP

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Remarks:

This study (OECD 422) investigates both the fertility toxicity and the developmental toxicity.

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted in accordance with OECD Test guideline No 422 and with the principles of GLP

Reason / purpose for cross-reference:

reference to same study

Remarks:

This study (OECD 422) investigates both the fertility toxicity and the developmental toxicity.

Qualifier:

equivalent or similar to guideline

Guideline:

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

Principles of method if other than guideline:

Study was in accordance with the range-finding assay described in OECD method 422.
Males were treated for 42 days, with a satellite high dose group retained for a further 15 days to demonstrate recovery after treatment.
The females were treated for 14 days prior to mating and then through gestation to lactation day 4. A high dose satellite recovery group of females was also retained for fifteen days following completion of treatment.

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

- Purity: 99.96%

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Crj:CD(SD)IGS rats used but no details provided regarding supplier
- Age at study initiation: (P) x wks; (F1) x wks No data
- Weight at study initiation: (P) Males: x-x g; Females: x-x g; (F1) Males: x-x g; Females: x-x g No data
- Fasting period before study: No data
- Housing: No data

- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%): No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): No data

IN-LIFE DATES: From: not stated To: not stated

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

0.5% sodium carboxymethylcellulose solution

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:

VEHICLE
- Justification for use and choice of vehicle (if other than water):0.5% sodium carboxymethylcellulose solution used as suspending agent

Details on mating procedure:

- M/F ratio per cage: 1:1.

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

No information provided

Duration of treatment / exposure:

Males were dosed for 42 days prior to mating; the females were treated for 14 days prior to mating and then until day 4 of lactation. The female satellite animals were treated or 42 days. The recovery period for males and satellite females was 14 days. The males were terminated on day 43 of treatment (day 15 of recovery) and the females were terminated on day 5 of lactation, satellite females on day 15 of recovery and the offspring were terminated 4 days after birth.

Frequency of treatment:

Once daily for up to 42 days

Details on study schedule:

As a screening study this investigation was limited to the parental generation and F1 offspring only. The repeated adminstration phase for males (42 days) and females (14 days) prior to mating provides some subacute toxicity data and the treatment of females through gestation gives some reproductive and developmental toxicity information.

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

No. of animals per sex per dose:

twelve; an additional five rats per sex were allocated to the satellite groups for retention through the recovery phase.

Control animals:

yes, concurrent vehicle

Details on study design:

No further details provided

Positive control:

Not applicable

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at weekly intervals - assessment in homecage, then in observers hands and then outside the homecage
Assessments included posture, sleeping, locomotion,vocalisations, tremors and convulsions, response to capture and handling, salivation, grading of heart beat, body temperature, exophthalmus and pupil size, exhibition of any discoloration of fur,skin or lacrimation. Outside the cage the assessment of posture, grooming, vocalisations, occurrence of straub tail, gait, tremor, convulsion pilo-erection and palpebral opening; exploration and respiratory rate and any exhibiion of stereotypy or bizarre behaviour.

BODY WEIGHT: recorded on days 1, 7, 14, 21, 28, 35 and 42 of treatment and days 1, 7, and 14 of recovery for males.
Females were weighed on days 1, 7, and 14 of treatment; days 0, 7, 14 and 20 of pregnancy and days 0 and 4 of lactation

Food consumption was recorded for the males and for the satellite females (treated at 200 mg/kg) on days 1-2, 7-8, 14-15, 29-30, 35-36 and 41-42 and then days 6-7 and 13-14 of the recovery phase.


Urinalysis was performed on Day 31 and 32 for males and females respectively
Necropsy was completed on termination of treatment or after completion of the recovery phase or day 5 of lactation

The reproductive performance of the parents was recorded for the twelve pairings per treatment group; the number of pairs copulating provided the copulation index and the number of pregnant females was used to calculate the fertility index. the mean number of days from pairing to copulation was also calculated

Oestrous cyclicity (parental animals):

All females examined. The number of rats showing a 4 day cycle in the pre-treatment phase was recorded, together with number with 5-day cycle. Mean cycle duration was calculated

Sperm parameters (parental animals):

no data

Litter observations:

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring on day 0 of lactation:
number of pups, stillbirths, live births, birth index and live birth index

Bodyweights recorded on day 0 and 4 of lactation

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

Necropsy of live pups surviving to lactation day 4- examination of external and visceral changes

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals following day 42 of treatment or on day 15 of the recovery phase.
- Maternal animals: All surviving animals on day 5 of lactation or on day 15 for the satellite animals in the recovery phase.

GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations including the cervical, thoracic, and abdominal viscera.

HISTOPATHOLOGY / ORGAN WEIGHTS
The tissues indicated in the attached Table were prepared for microscopic examination and weighed, respectively.

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring were sacrificed at 4 days of age.
- These animals were subjected to macroscopic postmortem examinations for external and visceral changes

Statistics:

No data

Reproductive indices:

The reproductive performance of the parents was recorded for the twelve pairings per treatment group; the number of pairs copulating provided the copulation index and the number of pregnant females was used to calculate the fertility index. the mean number of days from pairing to copulation was also calculated

Offspring viability indices:

Number of newborn, delivery index, number of live newborn, birth index and live bith index calculated on day 0 of lactation. On day 4 of lactation the number of live pups, viability index and sex ratio were calculated.

Clinical signs:

no effects observed

Description (incidence and severity):

daily observations showed no adverse reactions; detailed clinical assessment revealed no treatment related changes

Body weight and weight changes:

no effects observed

Description (incidence and severity):

bodyweights for males and females showed no significant differences from controls at any timepoint. Food consumption showed no significant treatment related differences

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

bodyweights for males and females showed no significant differences from controls at any timepoint. Food consumption showed no significant treatment related differences

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

liver histopathology in males at 200 mg/kg bw.d

Other effects:

not examined

Reproductive function: oestrous cycle:

no effects observed

Description (incidence and severity):

No significant effects recorded

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Oral administration of 4,4'-biphenyldiol at dose levels of 8, 40 or 200 mg/kg bw/day did not cause death or a moribund condition in any animals. None of the scores obtained during detailed clinical observations differed in a biologically significant manner between the control and the compound-treated groups.
No apparent changes were observed in general clinical conditions, except that urine in the 200 mg/kg-treated group became cloudy with elapse of time after excretion. Urinalysis was performed on treatment days 31 and 32 in male and female rats, respectively; calcium oxalate-like urinary crystal sediments were found in males given 200 mg/kg and in females given 40 or 200 mg/kg. Turbidity was enhanced at dose levels of 40 or 200 mg/kg, and urinary specific gravity was decreased in these females. These changes in urine parameters were not found when urinalysis was performed 11 days after cessation of the treatment (on day 11 of recovery) in either sex for the satellite animals.
Body weight, weight gain and food consumption were not affected by treatment at any dose level in either sex. No animals showed any abnormality in functional parameters after the final treatment.
At necropsy on termination of the treatment, no apparent effects of the compound were found on haematological or blood-biochemical examination at any dose level of the compound in either sex.
No effects of the compound were apparent in the female organs, including their weights or macroscopic or microscopic findings.
In contrast, 200 mg/kg of the compound exerted effects on male livers, with significant increase in relative weight, darkening or enlargement of the macroscopic appearance, development of centrilobular hepatocyte hypertrophy and reduction in occurrence of periportal fatty change. However, no animals showed any abnormality in functional observations on day 14 of the recovery period. At necropsy on day 15 of recovery, changes in the liver were not found in males given 200 mg/kg. In females given 200 mg/kg for 42 days and killed for necropsy on day 15 of recovery (satellite group), there were similarly no abnormal findings.

The treatment did not affect parameters of reproductive performance, such as the estrous cycle, ovulation, mating, implantation, delivery or lactational condition at any dose level. No adverse effects of the compound were observed on viability, morphology or growth of offspring.

Key result

Dose descriptor:

NOAEL

Remarks:

General toxicity

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Liver effects at 200 mg/kg bw/day (urinary turbidity at 40 and 200 mg/kg bw/d is not considered to be of toxicological significance).

Key result

Dose descriptor:

NOEL

Remarks:

Reproductive toxicity

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No evidence of reproductive toxicity was seen in this study at the highest dose level tested of 200 mg/kg bw/d

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Histopathological findings:

not specified

There were no adverse effects of administration on offspring viability, morphology or growth.

Key result

Dose descriptor:

NOEL

Remarks:

Developmental toxicity

Generation:

F1

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No evidence of developmental toxicity was seen in this study at the highest dose level tested of 200 mg/kg bw/d

Key result

Reproductive effects observed:

no

The no observed adverse effect level (NOAEL) for repeat dose toxicity of 4,4'- biphenyldiol is considered to be 40 mg/kg bw/d in both sexes. The NOAEL for reproductive toxicity is considered to be 200 mg/kg bw/d, in the absence of any relevant effects.

Summary of oestrous cycle data for females treated with 4,4’-biphenyldiol

	4,4’-biphenyldiol
	0 (0.5% CMC Na solution, 5 mL/kg bw	8 mg/kg bw/day	40 mg/kg bw/day	200 mg/kg bw/day
Number of females examined	12	12	12	12
Number of females with 4-day cycle in pre-treatment period	12	12	12	12
Number of females in treatment period with 4-day cycle or 5 day cycle	12 0	11 1	12 0	12 0
Mean length of oestrous cycle (days)	4.0	4.0	4.0	4.0
Number of vaginal oestrous during mating phase	1.0	1.0	1.0	1.0

 

Reproductive performance of rats treated with 4,4’-biphenyldiol

	4,4’-biphenyldiol
	0 (0.5% CMC Na solution, 5 mL/kg bw	8 mg/kg bw/day	40 mg/kg bw/day	200 mg/kg bw/day
Number of pairs examined	12	12	12	12
Number of pairs copulated	11	11	12	12
Copulation index	91.7	91.7	100	100
Number of pregnant females	11	11	10	12
Fertility index	100	100	83.3	100
Mean number of pairing days to copulation	2.5 ± 1.1	2.6 ± 1.2	2.7 ± 0.8	2.7 ± 1.2

 

Development of pups up to day 4 of lactation

	4,4’-biphenyldiol
	0 (0.5% CMC Na solution, 5 mL/kg bw	8 mg/kg bw/day	40 mg/kg bw/day	200 mg/kg bw/day
Number of pregnant females	12	12	10	12
Number of pregnant females with live newborns	11	11	10	12
Gestation index	100	100	100	100
Gestation length in days	22.4 ± 0.5	22.4 ± 0.5	22.0 ± 0.0	22.4 ± 0.5
Number of corpora lutea	15.9 ± 1.6	16.5 ± 1.1	16.2 ± 1.2	15.2 ± 1.5
Number of implantations	15.5 ± 1.7	14.3 ± 3.6	16.0 ± 1.6	14.7 ± 1.72
Implantation index	97.1 ± 4.3	86.9 ± 21.6	98.7 ± 4.2	96.7 ± 5.3
Day 0 of lactation
Number of newborns	14.5 ± 2.3	13.8 ± 4.0	15.1 ± 1.7	14.0 ± 1.8
Delivery index	93.2 ± 1.1	94.6 ± 12.2	94.4 ± 4.8	95.5 ± 5.2
Number of live newborns	14.3 ± 2.3	13.8 ± 4.0	14.6 ± 1.6	12.8 ± 2.9
Birth index	92.0 ± 7.6	94.6 ± 12.2	91.5 ± 8.1	88.8 ± 20.1
Live birth index	98.7 ± 3.0	100.0 ± 0.0	97.0 ± 7.5	93.3 ± 20.8
Sex ratio on Day 0	54.8 ± 14.5	49.4 ± 17.4	52.3 ± 15.1	51.6 ± 14.7
Day 4 of lactation
Number of live pups	13.9 ± 2.1	13.6 ± 4.0	14.5 ± 1.5	12.4 ± 4.2
Viability index	97.7 ± 4.0	98.8 ± 2.6	99.4 ± 2.0	91.7 ± 28.9
Sex ratio on Day 4	54.4 ± 14.9	49.3 ± 17.9	52.1 ± 15.9	50.8 ± 15.2

 

Pup bodyweights up to Day 4 of lactation

	4,4’-biphenyldiol
	0 (0.5% CMC Na solution, 5 mL/kg bw	8 mg/kg bw/day	40 mg/kg bw/day	200 mg/kg bw/day
Day 0 of lactation
Number of live newborns
Male	7.7 ± 2.1	6.9 ± 3.0	7.6 ± 2.1	6.5 ± 2.2
Female	6.5 ± 3.0	6.9 ± 3.3	7.0 ± 2.6	6.3 ± 2.7
Bodyweight of live newborn (g)
Male	6.8 ± 0.8	6.9 ± 0.8	6.5 ± 0.5	6.6 ± 0.8
Female	6.6 ± 0.6	6.6 ± 0.7	6.0 ± 0.4	6.2 ± 0.8
Day 4 of lactation
Number of live pups
Male	7.5 ± 2.3	6.8± 3.1	7.5± 2.2	6.8± 2.0
Female	6.4 ± 2.2	6.8± 3.2	7.0 ± 2.6	6.7± 2.5
Bodyweight of pups (g)
Male	10.6 ± 1.7	10.7 ± 1.1	10.2 ± 1.1	10.8 ± 1.0
Female	10.3 ± 1.4	10.4 ± 1.4	9.8 ± 1.0	10.0 ± 0.9

 

Pup morphology findings

	4,4’-biphenyldiol
	0 (0.5% CMC Na solution, 5 mL/kg bw	8 mg/kg bw/day	40 mg/kg bw/day	200 mg/kg bw/day
Dead pups
Number of dead pups examined	3	1	6	12
External examinations	3	1	6	12
Visceral examinations	0	0	5	1
Number of pups with external changes	0	0	0	0
Number of pups with visceral changes	0	0	0	0
Live pups
At birth (day 0)
Number of newborns examined	157	152	146	154
Number of newborns with external changes	0	0	0	0
At necropsy (day 4 of lactation)
Number of pups examined	153	150	145	149
Number of pups with external changes	0	0	0	0
Number of pups with visceral changes	0	0	0	0

 

Conclusions:

The treatment up to 200 mg/kg bw/d did not affect the reproductive performance of parental animals or the early development of their offspring. The no observed adverse effect dose level (NOAEL) for repeat dose toxicity of 4,4'-biphenyldiol is considered to be 40 mg/kg/day for both sexes of animals. The NOAEL for reproductive toxicity is considered to be 200 mg/kg bw/d, in the absence of any findings.

Executive summary:

A combined repeat dose and reproductive/developmental toxicity screening test was conducted in rats according to the OECD Test Guideline 422 with 4,4'-biphenyldiol. No effects on fertillity or reproductive parameters (oestrus cyclicity, mating, implantation or lactation) were observed at any dose level. In the absence of any effects on reproductive parameters, a NOAEL for reproductive toxicity of 200 mg/kg bw/d can be determined. A NOAEL for general toxicity of 40 mg/kg bw/d can be determined based on liver effects at the highest dose level. Effects of treatment on urinalysis parameters seen at 40 and 200 mg/kg bw/d are not considered to be of toxicological significance.

 

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Biphenyl-4,4'-diol

EC Number:

202-200-5

EC Name:

Biphenyl-4,4'-diol

Cas Number:

92-88-6

Molecular formula:

C12H10O2

IUPAC Name:

[1,1'-biphenyl]-4,4'-diol

Details on test material:

No further details.

Specific details on test material used for the study:

- Purity: 99.96%

Test animals

Species:

rat

Strain:

Crj: CD(SD)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Crj:CD(SD)IGS rats used but no details provided regarding supplier
- Age at study initiation: (P) x wks; (F1) x wks No data
- Weight at study initiation: (P) Males: x-x g; Females: x-x g; (F1) Males: x-x g; Females: x-x g No data
- Fasting period before study: No data
- Housing: No data

- Diet (e.g. ad libitum):
- Water (e.g. ad libitum):
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%): No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): No data

IN-LIFE DATES: From: not stated To: not stated

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

0.5% sodium carboxymethylcellulose solution

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:

VEHICLE
- Justification for use and choice of vehicle (if other than water):0.5% sodium carboxymethylcellulose solution used as suspending agent

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

No information provided

Details on mating procedure:

- M/F ratio per cage: 1:1.

Duration of treatment / exposure:

Males were dosed for 42 days prior to mating; the females were treated for 14 days prior to mating and then until day 4 of lactation. The female satellite animals were treated or 42 days. The recovery period for males and satellite females was 14 days. The males were terminated on day 43 of treatment (day 15 of recovery) and the females were terminated on day 5 of lactation, satellite females on day 15 of recovery and the offspring were terminated 4 days after birth.

Frequency of treatment:

Once daily for up to 42 days

Duration of test:

6 weeks

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

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

Doses / concentrations 2

Dose / conc.:

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

Doses / concentrations 3

Dose / conc.:

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

Doses / concentrations 4

Dose / conc.:

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

No. of animals per sex per dose:

twelve; an additional five rats per sex were allocated to the satellite groups for retention through the recovery phase.

Control animals:

yes, concurrent vehicle

Details on study design:

No further details provided.
As a screening study this investigation was limited to the parental generation and F1 offspring only. The repeated adminstration phase for males (42 days) and females (14 days) prior to mating provides some subacute toxicity data and the treatment of females through gestation gives some reproductive and developmental toxicity information.

The males and females were dosed for up to 42 days by oral gavage and this subacute exposure was used to address the short-term toxicology endpoints. Clinical signs, bodyweight gain, food consumption haematology, clinical chemistry and urinalysis parameters were recorded together with a limited functional observation battery, organ weights and macroscopic and microscopic examinations at termination.

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at weekly intervals - assessment in homecage, then in observers hands and then outside the homecage
Assessments included posture, sleeping, locomotion,vocalisations, tremors and convulsions, response to capture and handling, salivation, grading of heart beat, body temperature, exophthalmus and pupil size, exhibition of any discoloration of fur,skin or lacrimation. Outside the cage the assessment of posture, grooming, vocalisations, occurrence of straub tail, gait, tremor, convulsion pilo-erection and palpebral opening; exploration and respiratory rate and any exhibiion of stereotypy or bizarre behaviour.

A functional assessment was completed on the final day of treatment to assess various reflex responses.

BODY WEIGHT: recorded on days 1, 7, 14, 21, 28, 35 and 42 of treatment and days 1, 7, and 14 of recovery for males.
Females were weighed on days 1, 7, and 14 of treatment; days 0, 7, 14 and 20 of pregnancy and days 0 and 4 of lactation
Bodyweights and bodyweight gains are reported.

Food consumption was recorded for the males and for the satellite females (treated at 200 mg/kg) on days 1-2, 7-8, 14-15, 29-30, 35-36 and 41-42 and then days 6-7 and 13-14 of the recovery phase.

Urinalysis was performed on Day 31 and 32 for males and females respectively. Parameters assessed included colour, turbidity, pH, protein, glucose, ketone and bilirubin levels, occult blood, urobilinogen and presence in urinary sediment of crystals by incidence and type/shape and urinary specific gravity.

Clinical pathology in the form of standard haematology and biochemical parameters were assessed on Day 43 of treatment and on Day 15 of the recovery phase for male rats and on Day 5 of lactation for the females.

Organ weights were recorded on Day 43 of treatment and on Day 15 of the recovery phase for male rats and on Day 5 of lactation for the females.


Necropsy was completed on termination of treatment or after completion of the recovery phase or on day 5 of lactation. Macroscpic findings were recorded at each scheduled necropsy. Histopathological findings were documented for tissues sampled following each of the scheduled necropsy events. The list of tissues examined was in accordance with the test guideline.

The reproductive performance of the parents was recorded for the twelve pairings per treatment group; the number of pairs copulating provided the copulation index and the number of pregnant females was used to calculate the fertility index. the mean number of days from pairing to copulation was also calculated

All females examined for oestrous cyclicity . The number of rats showing a 4 day cycle in the pre-treatment phase was recorded, together with number with 5-day cycle. Mean cycle duration was calculated

Ovaries and uterine content:

No data

Fetal examinations:

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring on day 0 of lactation:
number of pups, stillbirths, live births, birth index and live birth index

Bodyweights recorded on day 0 and 4 of lactation

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

Necropsy of live pups surviving to lactation day 4- examination of external and visceral changes

Statistics:

No data

Indices:

Number of newborn, delivery index, number of live newborn, birth index and live bith index calculated on day 0 of lactation. On day 4 of lactation the number of live pups, viability index and sex ratio were calculated.

Historical control data:

No data

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
Oral administration of 4,4'-biphenyldiol at dose levels of 8, 40 or 200 mg/kg bw/day did not cause death or a moribund condition in any animals. None of the scores obtained during detailed clinical observations differed in a biologically significant manner between the control and the compound-treated groups.
No apparent changes were observed in general clinical conditions, except that urine in the 200 mg/kg-treated group became cloudy with elapse of time after excretion. Urinalysis was performed on treatment days 31 and 32 in male and female rats, respectively, calcium oxalate-like urinary crystal sediments were found in males given 200 mg/kg and in females given 40 or 200 mg/kg. Turbidity was enhanced at dose levels of 40 or 200 mg/kg, and urinary specific gravity was decreased in these females. These changes in urine parameters were not found when urinalysis was performed 11 days after cessation of the treatment (on day 11 of recovery) in either sex for the satellite animals.
Body weight, weight gain and food consumption were not affected by treatment at any dose level in either sex. No animals showed any abnormality in functional parameters after the final treatment.
At necropsy on termination of the treatment, no apparent effects of the compound were found on haematological or blood-biochemical examination at any dose level of the compound in either sex.

The reproductive and developmental toxicity indices evaluated in this screening study indicated no adverse effects on the dams. No effects were apparent in the female oestrous cycle either during the pre-treatment, mating or treament phases. The reproductive indices included the numbers of pairings examined, copulating and the number of resulting pregnant females and the length of pairing time required before copulation. There were no changes between control and treated groups.

Effect levels (maternal animals)

Key result

Dose descriptor:

NOAEL

Effect level:

200 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

Results (fetuses)

Fetal body weight changes:

no effects observed

Reduction in number of live offspring:

no effects observed

External malformations:

no effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
There were no adverse effects of administration on offspring viability, morphology or growth.
Pup development indices were evaluated to assess the duration of gestation, numbers of corpora lutea and implantations, the numbers of pups born, numbers of live born and sex ratio for the liveborn pups and survival and viability of pups to day 4 of lactation was also evaluated . None of the comparisons between treated and control groups revelaed any significant changes in these indices or any statistically significant effects. Similarly no effects were apparent when newborn or neonate (lactation day 4) pup weights were assessed.

Morphological evaluations for external and visceral changes showed no effects on the live pups at birth or those that survived to lactation Day 4. The dead pups examined (3 controls and 1, 6 or 12 pups in the 8, 40 or 200 mg/kg bw/day groups) also had no external and visceral changes .

Effect levels (fetuses)

Key result

Dose descriptor:

NOAEL

Effect level:

>= 200 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No effect observed

Overall developmental toxicity

Key result

Developmental effects observed:

no

Any other information on results incl. tables

Combined repeat dose and reproductive/developmental toxicity screening test for 4,4’-biphenyldiol

	4,4’-biphenyldiol mg/kg bw/day
	0	8	40	200
No. of females examined	12	12	12	12
No. of females showing 4-day cycle in pre-treatment phase	12	12	12	12
No. of females showing 4-day cycle in treatment phase	12	11	12	12
No. of females showing 4 and 5-day cycle in treatment phase	0	1	0	0
Mean length of oestrous cycle in days	4.0±0.0	4.0±0.1	4.0±0.0	4.0±0.0
Number of vaginal oestrous during mating period	1.0±0.0	1.0±0.0	1.0±0.0	1.0±0.0

 

	4,4’-biphenyldiol mg/kg bw/day
	0	8	40	200
No. of pairs examined	12	12	12	12
No. of pairs copulated	11	11	12	12
Copulation index	91.7	91.7	100.0	100.0
No. of pregnant females	11	11	10	12
Fertility index	100.0	100.0	83.3	100.0
Number of pairing days  to copulation	2.5±1.1	2.6±1.2	2.7±0.8	2.7±1.2

 

  Development of pups up to Day 4 of lactation

	4,4’-biphenyldiol mg/kg bw/day
	0	8	40	200
No. of pregnant females	11	11	10	12
No. of pregnant females with live neonates	11	11	10	12
Gestation index	100	100	100	100
Gestation length in days	22.4±0.5	22.4±0.5	22.0±0.0	22.4±0.5
Number of corpora lutea	15.9±1.6	16.5±1.1	16.2±1.2	15.2±1.5
Number of implantations	15.5±1.7	14.3±3.6	16.0±1.6	14.7±1.7
Implantation Index	97.1±4.3	86.9±21.6	98.7±4.2	96.7±5.3
Day 0 of lactation
Number of newborn	14.5±2.3	13.8±4.0	15.1±1.7	14.0±1.8
Delivery index	93.2±6.9	94.6±12.2	94.4±4.8	95.5±5.2
Number of live newborn	14.3±2.3	13.8±4.0	14.6±1.6	12.8±2.9
Birth index	92.0±7.6	94.6±12.2	91.5±8.1	88.8±20.1
Live birth index	98.7±3.0	100.0±0.0	97.0±7.5	93.3±20.8
Sex ratio on day 0	54.8±14.5	49.4±17.4	52.5±15.1	51.6±14.7
Day 4 of lactation
Number of live pups	13.9±2.1	13.6±4.0	14.5±1.5	12.4±4.2
Viability index	97.7±4.0	98.8±2.6	99.4±2.0	91.7±28.9
Sex ratio on day 4	54.4±14.9	49.3±17.9	52.1±15.9	50.8±15.2

The vehicle control was 5 ml/kg of 0.5% CMC Na solution.
Gestation index      (number of pregnant females with live newborns/number of pregnant females) x 100,%
Implantation index (number of implantations/number of corpora lutea) x 100,%
Delivery index        (number of newborns/number of implantations) x 100,%
Birth index             (number of live newborns/number of implantations) x 100,%
Live birth index      (number of live newborns/number of newborns) x 100,%
sex ratio (day 0)     (number of male live newborns / number of live newborns) x 100,%
viability index        (number of live pups on day 4 of lactation/ number of live newborns) x 100,%
sex ratio (day 4)     (number of male live pups on day 4 of lactation / number of live pups on day 4 of lactation) x 100,%

Bodyweight of pups up to Day 4 of lactation

	4,4’-biphenyldiol mg/kg bw/day
	0	8	40	200
Day 0 of lactation
Number of live newborn
male	7.7±2.1	6.9±3.0	7.6±2.1	6.5±2.2
female	6.5±2.5	6.9±3.3	7.0±2.6	6.3±2.7
Birthweight of live newborn
Males	6.8±0.8	6.9±0.8	6.5±0.5	6.6±.0.8
females	6.6±0.6	6.6±0.7	6.0±0.4	6.2±0.8
Day 4 of lactation
Number of live pups
Males	7.5±2.3	6.8±3.1	7.5±2.2	6.8±2.0
females	6.4±2.2	6.8±3.2	7.0±2.6	6.7±2.5
Birthweight of pups
Males	10.6±1.7	10.7±1.1	10.2±1.1	10.8±1.0
females	10.3±1.4	10.4±1.4	9.8±1.0	10.0±0.9

Morphological findings of pups

	4,4’-biphenyldiol mg/kg bw/day
	0	8	40	200
Dead pups
Number of dead pups examined	3	1	6	12
External observations	3	1	6	12
Visceral observations	0	0	5	1
No. of pups with external changes	0	0	0	0
No. of pups with visceral changes	0	0	0	0
Live pups at birth (Day 0)
Number of live neonates examined	157	152	146	154
Number with external changes	0	0	0	0
At necropsy on Day 4
Number of pups examined	153	150	145	149
No. of pups with external changes	0	0	0	0
No. of pups with visceral changes	0	0	0	0

Applicant's summary and conclusion

Conclusions:

Treatment with up to 200 mg/kg bw/d did not affect early offspring development. The no observed adverse effect level (NOAEL) for repeat dose toxicity of 4,4'-biphenyldiol is considered to be 40 mg/kg bw/d. In the absence of any effects on the parameters measured. the NOAEL for developmental toxicity is considered to be 200 mg/kg/ bw/d.

Executive summary:

A combined repeat dose and reproductive/developmental toxicity screening test was conducted in rats according to the OECD Test Guideline 422 with 4,4'-biphenyldiol. No effects on developmental parameters were observed at any dose level. In the absence of any effects on developmental parameters, a NOAEL for developmental toxicity of 200 mg/kg bw/d can be determined. A NOAEL for general toxicity of 40 mg/kg bw/d can be determined based on liver effects at the highest dose level. Effects of treatment on urinalysis parameters seen at 40 and 200 mg/kg bw/d are not considered to be of toxicological significance.