sodium 2-{N-[(3,5-difluorophenyl)carbamoyl]ethanehydrazonoyl}nicotinate

Toxicity to reproduction

Administrative data

Endpoint:

two-generation reproductive toxicity

Remarks:

based on test type (migrated information)

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

1994-11-24 to 1996-05-20

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted under the regulations of GLP and the respective guideline. A read-across approach was used. For justification please refer to IUCLID section 13.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPP 83-4 (Reproduction and Fertility Effects)

Version / remarks:

November 1982

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Version / remarks:

May 1983

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: MAFF 59 NohSan No 4200, January 1985

Deviations:

no

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

109293-97-2

EC Number:

600-910-3

Cas Number:

109293-97-2

IUPAC Name:

109293-97-2

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BRL Breeding laboratories, CH 4414-Füllinsdorf, Switzerland
- Age at study initiation: P: 8 wks; F1: 8 wks
- Weight at study initiation: weight range at study initiation ±20 % of the mean value for each sex
- Fasting period before study: no
- Housing: individual
- Diet: KLIBA powdered diet no. 32-343-4., ad libitum
- Water: tap water, ad libitum
- Acclimation period: 14 to 21 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23 ± 2
- Humidity (%): 60 ± 15
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 1995-10-13 To: 1996-05-20

BATCH HEALTH CHECK
During the accliamatization phase, blood was drawn for White Bolld Cell differential counts and cirus seology frim the rats allocated to the batch health check group (BHC). After the vlood collection, the BHC animals were sacrificed and necropsied. A sample of all macroscopic abnormalities and also lung, liver, kidney, spleen and heart was fixed in buffered formalin and examined histologically. Animals allocated to the study were examined by a veterinarien during the acclimatization period before beeing authorized for use in the study.

Administration / exposure

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Remarks:

in diet

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet: A 5 % premix was made freshly each week. Final diets were prepared weekly by direct dilution of the premix, except for the 500 ppm level, which was made by dilution of the 8000 ppm level and mixed for at least 20 min.
- Mixing appropriate amounts of the powdered test substance with powdered diet (incl. a 10 minutes dispersion at the ca. 1:4 test substance:diet stage)

Details on mating procedure:

- M/F ratio per cage: 1/1
- Length of cohabitation: for a maximum of 21 days
- Proof of pregnancy: vaginal plug and sperm in vaginal smear referred to as day 0 of pregnancy
- After successful mating each pregnant female was caged individually
- Any other deviations from standard protocol: An interval of minimum 10 days (after last litters weaned) was inserted between the F1A- and F1B mating.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Test substance stability and homogeneity in diet has previously been confirmed in SANDOZ Study No. 448R. During the study, samples of diets prepared for week 1 and then at 3-monthly intervals were analyzed for test substance content to check the accuracy of mixing. Additionally the homogeneity of the final diets prepared for week 1 were analyzed.

Diet samples were analyzed for the test item content using HPLC method developed, verified and adapted during the study. The account of the adaption of the analytical method was the low solubility of the test substance in the exraction solvent and an extension of the chromatographic separation.

Extraction method I:
Rat diet was extracted with methanole by ultrasonication for 15 minutes. After standing for 10 minutes to allow sedimentation of solids an aliquot of approx. 20 mL was filtered through paper filter. The clear solution was diluted with acetonitrile and analysed for the test item by HPLC-UV.

HPLC determination method I:
Column: ODS-Hypersil RP-18, particle size: 5 µm (LC6), 250 x 4.6 mm
Mobile phase: 0.5 % aqeous solution of trifluoroacetic acid / acetonitrile (1:1, v:v)
Gradient: isochratic
Flow rate: 1.0 mL/min
Volume injected: 100 - 500 µL
Wavelength: 239 nm

Extraction method II:
Rat diet was extracted with acetonitrile containing 5 % dimethylsulfxode by ultrasonication for 15 minutes and by vigorous shaking before and after ultrasonication. After standing for 5 minutes to allow sedimentation of solids an aliquot of approx. 3 mL was filtered through a 0.45 µm disposable filter. The clear solution was diluted with acetonitrile/5% demethylsulfoxide and analysed for the test item by HPLC-UV.

HPLC determination method II:
Column: Zorbax SB-C18, particle size: 4 µm (LC7), 150 x 2.1 mm
Mobile phase: Solvent A: acetonitrile; solvent B: 1 % aqueous solution of acetic acid (v:v)
Gradient: 0 min: A 25 %, B 75 % - 9 min: A 45 %, B 55 % - 11 min: A 60 %, B 40 %
Flow rate: 0.2 mL/min
Volume injected: 3 µL
Wavelength: 239 nm

The analytical results confirmed an acceptable homogeneity of the diet mixtures. The results of the reanalysis proved that diet samples can be stored for more than 9 months under deep-frozen conditions without any degradation.
The analytical results confirm that a correct dosage occurred at each dose level (range : -1.3 % at dose levels 500 ppm, +1.2 % at dose level 2000 ppm, and +5.6 % at dose level 8000 ppm). With the exception of one analtical result at week 0 ( over-dosage of +20.8 %) all diet concentrations lie well between the acceptable limits ( ± 20 % of nominal for single analytical results, ± 10 % of nominal for averaged concentrations over the whole dosage period).
From the results of the analytical work obtained in this study part it is concluded that the test substance was homogeneously distributed in the diet and that concentrations of the test substance in the diet ensured adequate exposure of the test system.

Duration of treatment / exposure:

The test substance was administered during a 70-day F0-generation premating period and also during the mating, gestation and lactation periods of the F1A- and F1B-generations.
Selected F1A-animals were treated from weaning for at least an 84-day premating period and also during the mating, gestation and lactation periods of the F2A-generation.

Frequency of treatment:

Continously via feed

Details on study schedule:

- Selection of parents from F1 generation when pups were 21 days of age.
- Age at mating of the mated animals in the study: 15 weeks

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
500, 2000, 8000 ppm
Basis:
nominal in diet

Doses / concentrations 2

Remarks:

Doses / Concentrations:
30, 120, 500 mg/kg bw/day
Basis:
actual ingested
Male animals during pre-mating period.

Doses / concentrations 3

Remarks:

Doses / Concentrations:
40, 170, 700 mg/kg bw/day
Basis:
actual ingested
Female animals during pre-mating period.

No. of animals per sex per dose:

26 animals per sex per dose

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: Doses were selected on the basis of results obtained in a previously conducted reproduction pilot study.
- Rationale for animal assignment: random

Positive control:

not applicable

Examinations

Parental animals: Observations and examinations:

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: twice daily for mortility and ill health, except at weekends and holidays where they were only checked once daily, and once a week for a detailed clinical inspection

BODY WEIGHT: Yes
- Time schedule for examinations: Males were weighed at weekly intervals throughout the study. Females was weighed weekly during the premating period and on days 0, 7, 14 and 20 post coitum. Dams which had littered were weighed on days 0, 7, 14 and 21 post partum.

FOOD CONSUMPTION AND COMPOUND INTAKE:
Food consumption was measured weekly at the same intervals as recording of the bodyweight, except during the mating period in which males and females had access to the same feeder. Relative food consumption ratios and intake of the test substance were calculated on a weekly basis.

Oestrous cyclicity (parental animals):

From all F0- and F1-females daily vaginal smears were taken during the last 20 days of the corresponding premating period and for at least 10 days before the second mating period (F1B).
Vaginal smears were also taken from all "sperm negative" females during the entire second mating period (F1B). Based on the unaffected fertility in all matings the estrous parameters were not investigated.

Sperm parameters (parental animals):

From all F0 and F1 adult males sperm motility were videorecorded at necropsy, slides for sperm morphology prepared and fixed and the left testis stored at about -70° C for sperm count analyses. Based on the unaffected fertility parameters in all matings the sperm parameters have not been investigated.

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: no

PARAMETERS EXAMINED
The following parameters were examined in [F1 and F2] offspring:
The litters were examined for litter size, live birth, stillbirth and any gross anomalies. Litters were caged together with the dam until weaning on day 21 of lactation. Pups were sexed and weighed by sex on day 0, 4, 7, 14 and individually on day 21 of lactation. Litters were not standardized. The dams and pups were observed daily for survival and behavioral abnormalities in nesting and nursing.

GROSS EXAMINATION OF DEAD PUPS:
Dead young, except if excessively cannibalized or autolytical, were autopsied (F1A pups were completely preserved).

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals when not longer necessary for the assessment of reproductive effects.
- Maternal animals: All surviving animals after the last litter of each generation was weaned

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

ORGAN WEIGHTS
From all F0 and F1 parental animals the following organs were weighed:
Uterus (with cervix) ovaries (without oviducts), testes, single epididymis (total and cauda), seminal vesicles (with coagulating glands and their fluids), prostata, brain, liver, kidneys, adrenal glands spleen, and thymus.

HISTOPATHOLOGY
Histopathological examination of the following organs were restricted to all F0- and F1-parental animals from the control and high-dose group:
Vagina, uterus with cervix, ovaries with oviducts (minimum of 10 sections randomly selected from one completely sectioned ovary per female to quantify oocytes), testis, intact epididymis (longitudinal section), seminal vesicles, prostata, coagulating gland, pituitary, mammary gland liver and grossly abnormal tissue

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring not selected as parental animals and all F2 offspring were sacrificed on day 21 post partum.
- These animals were subjected to postmortem examinations (macroscopic and microscopic examination) as follows:
For the F1A generation the whole body was fixed. Special attention was paid to the organs of the reproductive system. The remaining pups were killed, necropsied and checked for possible defects.

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

ORGAN WEIGTHS
For all pups examined macroscopically (2 pups/litter) the following organs were weighed:
Ovaries (without oviducts), testes, brain, liver, kidneys, adrenal glands, spleen, and thymus.

HISTOPATHOLOGY
Based on the treatment unrelated necropsy findings no histopathology were performed for pups.

Statistics:

All parental and litter data were recorded on-line and processed by a VAX-computer based software package (PSA) , except necropsy observations which were recorded manually on paper. The necropsy data were transferred into a VAX-computer based software package and submitted to the Principal Investigator for histopathology. Food mixture preparations were recorded and processed by a PC based software package. Means, standard deviations and statistical analyses of the various data were calculated, where appropriate.

The following statistical tests were performed:
Parametric data: ANOVA followed by Dunnet's test. If ANOVA failed, the non-parametric test was used.
Non-Parametric data: Kruskal-Wallis be followed by Mann-Whitney-U.
Count data: Chi-square followed by Fisher's exact test.

Reproductive indices:

The following reproductive indices were calculated for each group:
- Mating Index: (number of females mated / number of females paired) x 100
- Fertility Index: (number of females pregnant / number of females mated) x 100
- Gestation Index: (number of females with liveborn / number of females pregnant) x 100

Offspring viability indices:

The following offspring viability indices were calculated for each group:
- Livebirth Index: (number of pups liveborn / number of pups delivered) x 100
- Viability Index: (number of pups surviving day 4 / number of pups liveborn) x 100
- Lactation Index: (number of pups surviving day 21 / number of pups surviving day 4) x 100

Results and discussion

Results: P0 (first parental generation)

Details on results (P0)

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
There were no clinical signs that distinguished treated animals from controls. The few non-scheduled deaths of parental animals were randomly distributed among groups and not considered to be related to treatment

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
Lower total body weight gains were recorded at 8000 ppm in F0 and F1 parental males, and in F0 and F1 parental females in pre-mating and pregnancy phases. Significantly reduced total body weight gains were also noted for F0 parental males at 2000 ppm. No effects were seen at 500 ppm.

The following statistically significant deviations from control mean in food consumption, expressed
in grams per kg body weight per day, were considered to be related to treatment:
- Higher food consumption in F0 males at 2000 and 8000 ppm, with a dose-related trend
- Higher food consumption in F1 males at 8000 ppm
- Higher food consumption in F0 females at 2000 and 8000 ppm during pregnancy phases, with a dose-related trend
- Higher food consumption in F1 females at 2000 and 8000 ppm during pre-mating and pregnancy phases, with a dose-related trend.

Maternal food consumption during the lactation phases did not distinguish treated animals from controls.

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS)
The mean parental test substance intake in relation to dietary test substance concentration was usually higher in animals at 8000 ppm than in animals at 500 or 2000 ppm, which reflects the generally higher food consumption values at 8000 ppm. For each exposure level, the mean test substance intake was highest during the pregnancy phases (approximately 3-fold higher than pre-mating levels and approximately 50% higher than lactation levels).

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
Based on the unaffected fertility in all matings the estrous parameters were not investigated.

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
Based on the unaffected fertility parameters in all matings the sperm parameters have not been investigated.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
The following statistically significant deviation from control mean was considered to be related to treatment:
The pre-coital interval (time to mating) was significantly shorter at 8000 ppm in the second F0 mating period. No statistically significant deviations in pre-coital interval were observed in the first F0 and F1 mating period, and the finding could, therefore, be incidental.
Mating, fertility, and gestation indices and the duration of gestation did not distinguish treated animals from controls.

ORGAN WEIGHTS (PARENTAL ANIMALS)
The following statistically significant deviations from control mean in parental animals were considered to be related to treatment:
The asolute and relative (to body and brain) weights of the seminal vesicles were higher in F1 parents at 2000 and 8000 ppm, with a dose-related trend. Higher relative seminal vesicles weight were also recorded in F0 parents at 8000 ppm. No morphological correlate was detected.

HISTOPATHOLOGY (PARENTAL ANIMALS)
The incidence, type and severity of histopathologic lesions did not distinguish treated parental animals from controls.

Effect levels (P0)

1

Dose descriptor:

NOAEL

Remarks:

(systemic toxicity)

Effect level:

2 000 ppm (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Lower weight gain and increased food consumption

Remarks on result:

other: Generation: F0 & F1 (migrated information)

2

Dose descriptor:

NOAEL

Remarks:

(systemic toxicity)

Effect level:

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

Based on:

test mat.

Sex:

male

Basis for effect level:

other: Lower weight gain and increased food consumption

Remarks on result:

other: Generation: F0 & F1 (migrated information)

3

Dose descriptor:

NOAEL

Remarks:

(systemic toxicity)

Effect level:

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

Based on:

test mat.

Sex:

female

Basis for effect level:

other: Lower weight gain and increased food consumption

Remarks on result:

other: Generation: F0 & F1 (migrated information)

4

Dose descriptor:

NOEL

Remarks:

(developmental)

Effect level:

2 000 ppm (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Lower weight gains and higher proportion of runts at 8000 ppm.

Remarks on result:

other: Generation: F1 & F2 (migrated information)

5

Dose descriptor:

NOEL

Remarks:

(developmental)

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Lower weight gains and higher proportion of runts at 2500 mg/kg bw/day.

Remarks on result:

other: Generation: F1 & F2 (migrated information)

Results: F1 generation

Details on results (F1)

VIABILITY (OFFSPRING)
Lower live birth and viability indices were observed in the F2A generation at 8000 ppm. One dam at 8000 ppm delivered all her F2A pups stillborn. The total pre-perinatal loss was significantly higher in the F2A generation at 8000 ppm. The lactation index was not affected.
The significantly lower viability index in the F1B generation at 500 ppm was not considered to be related to treatment in the absence of similar findings at higher dose levels. Mean litter size and sex ratio did not distinguish treated animals from controls.

BODY WEIGHT (OFFSPRING)
F1A male and female offspring at 8000 ppm showed significantly reduced weight gains during the lactation period, but similar effects were not observed in the F1B and F2A generations. No effects on body weight development of the offspring were noted in any generation at 2000 and 500 ppm.

ORGAN WEIGHTS (OFFSPRING)
The following statistically significant deviations from control mean in the offspring can not be excluded as possible treatment - related effects:
- Lower absolute and relative (to body) weights of the thymus in F1B males at 8000 ppm
- Lower absolute weights of the kidneys in F1B females at 8000 ppm
- Lower relative (to body) weights of the kidneys in F1B and F2A females at 8000 ppm

GROSS PATHOLOGY (OFFSPRING)
The following statistically significant deviations from control mean in the offspring were considered to be related to treatment:
- A higher proportion of undersized animals (runt) in the F1A and F1B generation at 8000 ppm.
- A higher percentage of F2A offspring at 8000 ppm were found to have no milk in the stomach.
There were no other necropsy findings in the offspring that distinguished treated animals from controls.

Effect levels (F1)

1

Dose descriptor:

NOEL

Remarks:

(reproductive performance)

Generation:

F1a

Effect level:

2 000 ppm (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Effects on Live Birth Index, Viability Index and increased Pre-Perinatal Loss in the F2-Generation at 8000 ppm.

2

Dose descriptor:

NOEL

Remarks:

(reproductive performance)

Generation:

F1a

Effect level:

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

Based on:

test mat.

Sex:

male

Basis for effect level:

other: Effects on Live Birth Index, Viability Index and increased Pre-Perinatal Loss in the F2-Generation at 550 mg/kg bw/day.

3

Dose descriptor:

NOEL

Remarks:

(reproductive performance)

Generation:

F1a

Effect level:

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

Based on:

test mat.

Sex:

female

Basis for effect level:

other: Effects on Live Birth Index, Viability Index and increased Pre-Perinatal Loss in the F2-Generation at 740 mg/kg bw/day.

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Table 1: Mean Body Weight Change (grams)

Sex	Study period	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Males	week 0 -32	F0	296.5	288.7	272.1	242.9 **
	week 0 -20	F1	230.5	233.4	217.1	199.8 **
	day 0-21 p.p.	F1A	35.5	37.7	34.1	30.0 **
		F1B	37.5	39.7	36.6	33.5
		F2A	33.3	34.4	35.4	34.3
Females	Pre-mating	F0	79.5	80.7	74.4	65.5 **
		F1	82.6	83.5	78.7	74.2 *
	1st pregnancy	F0	106.5	100.0	103.6	91.6 **
		F1	99.8	104.6	102.5	87.3 *
	2nd pregnancy	F0	107.9	101.6	114.7	90.6 **
	day 0-21 p.p.	F1A	34.7	35.9	33.4	29.8 **
		F1B	36.0	39.4	35.8	32.5
		F2A	32.9	33.8	35.5	33.8

*          p< 0.05

**         p< 0.01

 

Table 2: Mean Food Consumption (grams/kg bw/day)

Sex	Study period	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Males	week 0-32	F0	54,6	54,7	56,5	58,3 *
	week 0 -20	F1	61,2	62,1	63,2	69.0 **
Females	Pre-mating	F0	83.2	84.5	84.6	83.7
		F1	82.4	84.0	87.9 *	92.7 **
	1st pregnancy	F0	273.1	282.0	298.9 **	303.1 **
		F1	257.9	264.5	290. 0 **	308.4 **
	2nd pregnancy	F0	245.1	256.8	269.0 *	273.6 **
	1st lactation	F0	196.4	186.6	207.2	203.9
		F1	179.4	188.7	191.4	190.2
	2nd lactation	F0	161.8	143.6	173.8	184.1

*          p< 0.05

**         p< 0.01

 

Table 3: Mean Test Substance Intake (mg/kg bw/day)

Sex	Study period	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Males	week 0 -32	F0	-	27,3	113,1	466,2
	week 0 -20	F1	-	31,1	126,4	552,2
Females	Pre-mating	F0	-	42.2	169.2	669.6
		F1	-	42.0	175.9	742.0
	1st pregnancy	F0	-	141.0	597.7	2424.6
		F1	-	132.2	580.1	2467.3
	2nd pregnancy	F0	-	128.4	537.9	2188.7
	1st lactation	F0	-	93.3	414.4	1631.6
		F1	-	94.3	382.8	1521.6
	2nd lactation	F0	-	71.8	347.6	1472.4

 

Table 4: Litter data

Litter parameter	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Mean Litter Size (total)	F1A	11.7	10.3	11.8	11.3
	F1B	11.0	9.1	11.6	10.0
	F2A	11.2	11.7	11.0	10.0
Sex Ratio (% males)	F1A	48.5	47.5	50.5	41.6
	F1B	50.4	45.8	48.5	47.8
	F2A	49.0	49.0	50.0	53.3
Live Birth Index (%)	F1A	96	96	98	97
	F1B	97	95	94	99
	F2A	98	99	98	93 *
Viability Index (%)	F1A	99	96	99	97
	F1B	97	92	98	97
	F2A	98	98	98	88
Lactation Index (%)	F1A	98	93	99	99
	F1B	99	97	100	100
	F2A	99	97	98	97
Pre-Perinatal Loss (%)	F2A	11	10	11	21 **

*          p< 0.05

**         p< 0.01

 

Table 5: Necropsy Observation

Litter parameter	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Runt (%)	F1A	0.4	2.8	0.9	8.0 **
	F1B	0.0	2.2	0.0	14.0 **
	F2A	0.8	1.4	0.0	3.2
No milk in Stomach (%)	F1A	4.0	5.0	2.6	2.7
	F1B	1.9	3.3	3.3	2.6
	F2A	1.2	1.4	2.8	8.4 ** 5.2 % #

**         p< 0.01

#: excluding stillborn, no statistics performed

 

Table 6: Organ weights

Weight of thymus in males

Weight parameter	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Absolute weight (g)	F1B	0.196	0.215	0.174	0.158 **
	F2A	0.174	0.166	0.181	0.165
Relative to body weight	F1B	0.453	0.458	0.422	0.408 *
	F2A	0.429	0.413	0.431	0.402

 

Weight of kidneys in females

Weight parameter	Generation	0 ppm	500 ppm	2000 ppm	8000 ppm
Absolute weight (g)	F1B	0.485	0.518	0.483	0.419 *
	F2A	0.446	0.448	0.480	0.429
Relative to body weight	F1B	1.168	1.161	1.146	1.098 *
	F2A	1.132	1.131	1.120	1.075 *

*          p< 0.05

**         p< 0.01