Symclosene

Toxicity to reproduction

Administrative data

Endpoint:

three-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed to GLP and guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.35 (Two-Generation Reproduction Toxicity Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Sodium salt of cyanuric acid (s-triazinetriol)

IUPAC Name:

Sodium salt of cyanuric acid (s-triazinetriol)

Details on test material:

- Name of test material (as cited in study report): Sodium salt of cyanuric acid (s-triazinetriol)
- Substance type: powder
- Analytical purity: Equivalent to 77.05% cyanuric acid
- Lot/batch No.: 1785021-1

Test animals

Species:

rat

Strain:

other: Charles River CD

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc., Portage, Michigan, USA.
- Housing: Wire mesh cages
- Diet : ad libitum
- Water: ad libitum
- Acclimation period: 15 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-25
- Humidity (%): 50 ± 15%
- Air changes (per hr): 10-11
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: drinking water

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
A factor of 1.2979 was utilized in dosage calculations to adjust for the base composition (77.05%) of cyanuric acid in the test article. The appropriate amounts of the sodium salt of cyanuric acid (s-triazinetriol) were dissolved in tap water, utilizing a motor driven propeller, to permit administration at concentrations of 400, 1200 and 5375 ppm of s-triazinetriol. Each test solution was adjusted to a pH of 7.4 at approximately 25°C using glacial acetic acid or a 1% sodium hydroxide solution. The amounts of acid or base used were recorded. Fresh test solutions were prepared twice each week.

Details on mating procedure:

- M/F ratio per cage: 1 male per two females
- Length of cohabitation: 14 days
- Proof of pregnancy: vaginal plug and or vaginal smear referred to as day 0 of gestation
- After 7 days of unsuccessful pairing replacement of first male by another male with proven fertility.
- The F0 and F1 parents were mated twice to produce 'a' and 'b' offspring, the F2 parents were mated once to produce the F3 offspring

Duration of treatment / exposure:

Exposure period: Treatment was initiated at 36 days of age to the F0 generation and at 21 days of age to F1 and F2 parents of both sexes. Test solution was administered until termination of each generation
Premating exposure period (males): F0: minimum 100 days (14 weeks) of treatment, F1 and F2: minimum 120 days of treatment.
Premating exposure period (females): F0: minimum 100 days (14 weeks) of treatment, F1 and F2: minimum 120 days of treatment.

Frequency of treatment:

Ad libitum

Doses / concentrations

Remarks:

Doses / Concentrations:
400, 1200 and 5375 ppm (males F0 ~35, ~100, ~470 mg/kg bw/d; F1 ~36, ~110, ~500 mg/kg bw/d; F2 ~40, ~110, ~485 mg/kg bw/d; females, F0 ~64, ~185, ~950 mg/kg bw/d; F1 ~63, ~190, ~910 mg/kg bw/d; F2 ~65, ~195, ~970 mg/kg bw/d)
Basis:

No. of animals per sex per dose:

12 males 24 females / dose level

Control animals:

other: Vehicle (tap water), Sodium control (sodium hippurate 8056 ppm)

Details on study design:

The concentration of sodium hippurate was selected to permit the administration of an equal concentration of ionic sodium as that contributed by the test article at the high dose level.

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice each day
- Cage side observation included signs of overt toxicity, changes in general appearance, behaviour and mortality.


DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Weekly


BODY WEIGHT: Yes
- Time schedule for examinations: Weekly


FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes


WATER CONSUMPTION: Yes
- Time schedule for examinations: Weekly except during mating mating periods

Litter observations:

PARAMETERS EXAMINED
The following parameters were examined in F1 / F2 / F3 offspring:
The number and sex of pups, stillbirths, live births, presence of gross anomalies, weight gain, physical or behavioural abnormalities, pup survival through weaning, pup weight at birth and specified intervals during lactation.

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals
- Maternal animals: All surviving animals


HISTOPATHOLOGY:
Gonads and gross lesions

ORGAN WEIGHTS:
Adrenal glands, brain, heart, liver, ovaries (2), spleen, testes, epididymides (2) and thyroid.

Postmortem examinations (offspring):

SACRIFICE
- All F1b and F2b pups not selected as parents. All F3 pups retained after weaning.



ORGAN WEIGHTS:
Adrenal glands, brain, heart, liver, ovaries (2), spleen, testes, epididymides (2) and thyroid.

HISTOPATHOLOGY:
F1b and F2b pups (5/sex from control, high dose and sodium control) and F3 (5/sex/group) as follows: adrenals, aorta, bone (tibia with marrow), brain (longitudinal section), colon, duodenum, esophagus, eyes, heart, ileum, jejunum, kidney, liver, lungs, lymph node (mesenteric), mammary gland, ovaries, pancreas, pituitary, peripheral nerve, prostate, salivary gland, seminal vesicles, skeletal muscle, skin (with cervical lymph node), spleen, stomach, testes (with epididymis), thymus, thyroid (with parathyroids), thrachaea, urinary bladder, uterus, cervix, all the gross lesions, tissue masses, spinal cord and ureter

Statistics:

Analysis compared the treated groups to the control and sodium control groups and the control and sodium control groups were compared to each other. The parental body weights by sex were analyzed by one-way analysis of variance, Bartletts test for homogeneity of variances and the appropriate t-test (for equal or unequal variances). In all generations analyses were conducted at one week prior to the first mating, one week prior to the second mating and at termination of the generation. In addition, analyses were conducted at initiation of the F1 and F2 generations. Male and female indices were compared using the Chi-square test criterion with Yates' correction for 2 x 2 contingency tables and/or Fishers exact probability test. The proportion of live pups at birth per total number born and the survival indices at lactation days 4, 7, 14 and 21 were compared by the Mann-Whitney U-test. The mean numbers of liveborn pups per litter and mean body weights of pups were analyzed by one-way analysis of variance, Bartletts test for homogeneity of variances and the appropriate t-test (for equal or unequal variances). Organ weights by sex were analyzed by one-way analysis of variance, Bartlett's test for homogeneity of variances, and the appropriate t-test (for equal or unequal variances).

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Mortality:

mortality observed, non-treatment-related

Description (incidence):

2 control, 2 high-dose and 1 sodium control males failed to survive to scheduled sacrifice. One male control and one male in the high dose groups were sacrificed in extremis. All deaths and sacrifices occurred between weeks 11 and 34. Surviving animals showed no biologically significant effects.

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

effects observed, treatment-related

Description (incidence and severity):

an increase in high dose females was observed

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P0)

MALES:
Appearance, behaviour and mortality: 2 control, 2 high-dose and 1 sodium control males failed to survive to scheduled sacrifice. One male control and one male in the high dose groups were sacrificed in extremis. All deaths and sacrifices occurred between weeks 11 and 34. Surviving animals showed no biologically significant effects.
Body weights: no biologically significant effects were observed.
Food consumption: no effects.
Water consumption: no treatment effect was presumed.

FEMALES:
Appearance, behaviour and mortality: no effects.
Body weights: no biologically significant effects were observed.
Food consumption: no effects.
Water consumption: an increase in high dose females was observed.

Effect levels (P0)

1

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 470 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

mortality

reproductive performance

2

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 950 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

mortality

reproductive performance

Results: P1 (second parental generation)

General toxicity (P1)

Clinical signs:

no effects observed

Mortality:

mortality observed, non-treatment-related

Description (incidence):

one male in each of the high dose and sodium control groups failed to survive to scheduled sacrifice. Surviving animals showed no biologically significant effects.
one female from each of the control, low and mid dose and sodium control groups between week 38 and 63 exhibited no overt clinical signs prior to death. One control group female was sacrificed in extremis during study week 61. Surviving animals showed no biologically significant effects.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

a slight to moderate increase in the high dose and sodium control groups were observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

effects observed, treatment-related

Description (incidence and severity):

an increase in high dose and sodium control females was observed

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

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Details on results:

1.1.1 F1 males Appearance, behaviour and mortality: one male in each of the high dose and sodium control groups failed to survive to scheduled sacrifice. Surviving animals showed no biologically significant effects.
Body weights: a slight to moderate increase in the high dose and sodium control groups were observed.
Food consumption: no effects.
Water consumption: no treatment effect was presumed.
1.1.2 F1 females Appearance, behaviour and mortality: one female from each of the control, low and mid dose and sodium control groups between week 38 and 63 exhibited no overt clinical signs prior to death. One control group female was sacrificed in extremis during study week 61. Surviving animals showed no biologically significant effects.
Body weights: a slight to moderate increase in the high dose and sodium control groups were observed.
Food consumption: no effects.
Water consumption: an increase in high dose and sodium control females was observed.

Reproductive function / performance (P1)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P1)

No significant fluctuations in reproductive or litter parameters. Fertility indices, gestation lengths, litter sizes, pup survival to weaning and pup weights at parturition and throughout lactation were comparable with controls.

Effect levels (P1)

1

Key result

Dose descriptor:

NOAEL

Effect level:

>= 500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male

Basis for effect level:

mortality

2

Dose descriptor:

NOAEL

Effect level:

>= 910 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Basis for effect level:

mortality

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

effects observed, treatment-related

Description (incidence and severity):

an increase in high dose and sodium control females was observed

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings:

effects observed, treatment-related

Other effects:

no effects observed

Developmental neurotoxicity (F1)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F1)

Developmental immunotoxicity:

not examined

Details on results (F1)

F1 MALES:
Appearance, behaviour and mortality: one male in each of the high dose and sodium control groups failed to survive to scheduled sacrifice. Surviving animals showed no biologically significant effects.
Body weights: a slight to moderate increase in the high dose and sodium control groups were observed.
Food consumption: no effects.
Water consumption: no treatment effect was presumed.

F1 FEMALES:
Appearance, behaviour and mortality: one female from each of the control, low and mid dose and sodium control groups between week 38 and 63 exhibited no overt clinical signs prior to death. One control group female was sacrificed in extremis during study week 61. Surviving animals showed no biologically significant effects.
Body weights: a slight to moderate increase in the high dose and sodium control groups were observed.
Food consumption: no effects.
Water consumption: an increase in high dose and sodium control females was observed.

F2 MALES:
Appearance, behaviour and mortality: one 400 ppm male died during week 98. Two males in the 5375 ppm group died, one at week 83, one at week 100. Surviving animals showed no biologically significant effects.
Body weights: no biologically significant effects were observed. An increased incidence of calculi in the urinary bladder in the 5375 ppm males was related to the test article.
Food consumption: no effects.
Water consumption: no treatment effect was presumed.

F2 FEMALES:
Appearance, behaviour and mortality: one 400 ppm female died immediately prior to initiation of the generation. One female died in the sodium control group on day 20. Surviving animals showed no biologically significant effects.
Body weights: a slight to moderate increase in the mid dose group was observed.
Food consumption: no effects.
Water consumption: an increase in high dose and sodium control females was observed.

Effect levels (F1)

1

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

ca. 500 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

mortality

2

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

ca. 910 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

mortality

Results: F2 generation

General toxicity (F2)

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

one 400 ppm male died during week 98. Two males in the 5375 ppm group died, one at week 83, one at week 100. Surviving animals showed no biologically significant effects.
one 400 ppm female died immediately prior to initiation of the generation. One female died in the sodium control group on day 20. Surviving animals showed no biologically significant effects.

Mortality / viability:

mortality observed, non-treatment-related

Description (incidence and severity):

one 400 ppm male died during week 98. Two males in the 5375 ppm group died, one at week 83, one at week 100. Surviving animals showed no biologically significant effects.
one 400 ppm female died immediately prior to initiation of the generation. One female died in the sodium control group on day 20. Surviving animals showed no biologically significant effects.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

a slight to moderate increase in the mid dose group females was observed.
An increased incidence of calculi in the urinary bladder in the 5375 ppm males was related to the test article.

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

effects observed, treatment-related

Description (incidence and severity):

an increase in high dose and sodium control females was observed

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings:

no effects observed

Developmental neurotoxicity (F2)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F2)

Developmental immunotoxicity:

not examined

Details on results (F2)

1.1.1 F2 males Appearance, behaviour and mortality: one 400 ppm male died during week 98. Two males in the 5375 ppm group died, one at week 83, one at week 100. Surviving animals showed no biologically significant effects.
Body weights: no biologically significant effects were observed. An increased incidence of calculi in the urinary bladder in the 5375 ppm males was related to the test article.
Food consumption: no effects.
Water consumption: no treatment effect was presumed.
1.1.2 F2 females Appearance, behaviour and mortality: one 400 ppm female died immediately prior to initiation of the generation. One female died in the sodium control group on day 20. Surviving animals showed no biologically significant effects.
Body weights: a slight to moderate increase in the mid dose group was observed.
Food consumption: no effects.
Water consumption: an increase in high dose and sodium control females was observed.

Effect levels (F2)

1

Key result

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

ca. 190 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

mortality

2

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

ca. 970 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

mortality

Overall reproductive toxicity

Key result

Reproductive effects observed:

no

Lowest effective dose / conc.:

470 mg/kg bw/day (nominal)

Treatment related:

no

Any other information on results incl. tables

S-triazinetriol had no significant effect on survival, appearance or behaviour including nesting and nursing behaviour.  No cross generational trends indicative of a test article effect on parental body weight was noted, nor was food consumption affected.  A consistent cross generational trend of increased water consumption was noted in high dose females, which in the F₁ and F₂ generations was accompanied by a concurrent increase in sodium control female values, although the role of increased sodium intake versus that of cyanuric acid is unclear. 

The survival, general appearance, behaviour, mean body weights and food and water consumption of retained F₃ pups were uniform in all study groups.  Treatment with s-triazinetriol at concentrations of 5375 ppm or less did not induce significant fluctuations in reproductive or litter parameters.  Fertility indices, gestation length, litter size, pup survival to weaning and pup weights at parturition and throughout lactation of treated groups, including the sodium control were comparable to those of the controls.  An increased incidence of calculi in the urinary bladder in 5375 ppm F₂ males was related to the test article.  The findings with respect to female water consumption in the high-dose group and the post-mortem urinary bladder findings in the high-dose F₂ males had no biologically detrimental effect on the reproductive potential of the parents or on the growth and development of the offspring

Table A6_8_2(1)-1.  Table for Reproductive Toxicity Study
Parameter			Control 0 ppm		Low Dose 400 ppm		Medium Dose 1200 ppm		High Dose 5375 ppm		Sodium Control
		Genera­tion	m	f	m	f	m	f	m	f	m	f
Mortality	incidence	F1	0	2	0	1	0	1	1	0	1	1
		F2	0	0	1	1	0	0	2	0	0	1
		F3	0	0	0	0	0	0	1	0	0	1
Clinical Observations hydronephrosis	Incidence	P	3	0	0	2	0	3	5	4	2	0
		F1	0	0	1	5	1	2	3	3	2	3
		F2	0	0	1	1	0	1	0	3	1	3
Reproductive Performance
Mating index (%)	(%)	F1a		95.8		91.7		95.8		91.7		100
	(%)	F1b		95.0		95.2		81.0		100		95.5
	(%)	F2a		78.3		60.9		79.2		70.8		79.2
	(%)	F2b		77.3		65.2		82.6		91.7		100
	(%)	F3		95.8		68.2		87.5		91.7		100
Fertility index		F1a	90.9	83.3	100	87.5	91.7	87.5	91.7	83.3	90.9	95.8
		F1b	100	95.0	100	90.5	91.7	81.0	81.8	95.0	100	81.8
		F2a	83.3	56.5	75.0	60.9	66.7	54.2	100	66.7	90.9	75.0
		F2b	50.0	40.9	66.7	52.2	91.7	69.6	100*	70.8	90.9	56.5
		F3	100	95.8	58.3	50.0**	100	87.5	90.9	83.3	100	83.3
Gestation index	(%)	F1a		83.3		87.5		87.5		83.3		95.8
	(%)	F1b		95.0		90.5		81.0		95.0		81.8
	(%)	F2a		56.5		60.9		54.2		66.7		75.0
	(%)	F2b		40.9		52.2		69.6		70.8		56.5
	(%)	F3		95.8		68.2		87.5		91.7		100
Litter size	Mean	F2a	9.6		9.8		8.7		10		9.1
	Mean	F2b	10		9.3		8.7		9.1		9.1
	Mean	F3	9		9.8		9.7		9.9		8.8
Pup weight^#Mean	Lactation day 0	F2a	6.1		6.2		6.4		6.1		6.2
	Lactation day 0	F2b	6.0		6.4		6.3		6.1		6.5
	Lactation day 0	F3	6.4		6.3		6.1		5.9		5.9
Sex ratio	Male/female	F2a	57 : 68		64 : 73		51 : 48		88 : 72		82 : 82
	Male/female	F2b	41 : 49		57 : 54		71 : 68		74 : 71		55 : 63
	Male/female	F3	113: 93		53 : 55		105 : 99		95 : 102		76 : 92
Survival index^#	Lactation day 0	F1a	98.4		98.9		99.2		99.6		98.2
	Lactation day 0	F1b	95.7		98.8		98.0		94.4		97.3
	Lactation day 0	F2a	98.0		95.1		95.2		99.0		97.6
	Lactation day 0	F2b	100		100		97.8		90.2		99.4
	Lactation day 0	F3a	98.8		97.6		97.0		98.1		98.6
	Lactation day 4	F1a	98.7		99.3		98.9		98.7		97.0
	Lactation day 4	F1b	99.5		99.2		99.0		97.9		99.5
	Lactation day 4	F2a	98.6		100		98.3		99.5		99.0
	Lactation day 4	F2b	99.2		100		99.4		97.7		100
	Lactation day 4	F3a	99.2		100		96.9		98.8		98.1
	Lactation day 7	F1a	100		99.0		100		99.5		100
	Lactation day 7	F1b	100		100		100		99.4		99.
	Lactation day 7	F2a	100		100		98.1		100		99.4
	Lactation day 7	F2b	100		100		100		100		100
	Lactation day 7	F3a	99.5		100		100		99.5		96.5
	Lactation day 14	F1a	100		100		99.5		100		99.5
	Lactation day 14	F1b	100		100		100		100		100
	Lactation day 14	F2a	100		100		100		100		100
	Lactation day 14	F2b	100		100		99.3		100		100
	Lactation day 14	F3a	100		100		100		100		99.4
	Lactation day 21	F1a	99.5		100		100		100		100
	Lactation day 21	F1b	100		100		100		100		100
	Lactation day 21	F2a	100		100		99.0		100		95.9
	Lactation day 21	F2b	100		100		100		100		100
	Lactation day 21	F3a	100		100		99.5		100		100

* Significantly different from the control value (p < 0.05)

** Significantly different from the control value (p < 0.01)

^#Does not distiguish between male and female.

Applicant's summary and conclusion

Conclusions:

No biologically detrimental effect on the reproductive potential of the parents or on the growth and development of the offspring.