[[(phosphonomethyl)imino]bis[ethylenenitrilobis(methylene)]]tetrakisphosphonic acid, potassium salt

Toxicity to reproduction

Administrative data

Endpoint:

one-generation reproductive toxicity

Remarks:

based on test type (migrated information)

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

12.09. 1977 to 19.06.1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: 2c The study was conducted according to a test protocol that is comparable to the appropriate OECD test guideline. It was not compliant with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 415 [One-Generation Reproduction Toxicity Study (before 9 October 2017)]

Version / remarks:

Conducted prior to adoption of OECD test guideline.

Deviations:

yes

Remarks:

No analytical confirmation of exposure, no pre-mating exposure, no assessment of oestrus cycle or sperm analyses, no evaluation of sexual milestones in pup. Males treated only as F1 and F2 generation.

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

[[(phosphonomethyl)imino]bis[ethane-2,1-diylnitrilobis(methylene)]]tetrakisphosphonic acid

EC Number:

239-931-4

EC Name:

[[(phosphonomethyl)imino]bis[ethane-2,1-diylnitrilobis(methylene)]]tetrakisphosphonic acid

Cas Number:

15827-60-8

IUPAC Name:

[(bis{2-[bis(phosphonomethyl)amino]ethyl}amino)methyl]phosphonic acid

Constituent 2

Reference substance name:

[[(phosphonomethyl)imino]bis[ethane-2,1-diylnitrilobis(methylene)]]tetraki sphosphonic acid

IUPAC Name:

[[(phosphonomethyl)imino]bis[ethane-2,1-diylnitrilobis(methylene)]]tetraki sphosphonic acid

Test animals

Species:

rat

Strain:

Long-Evans

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Females: Blue Spruce Farms. Males: BioDynamics Inc. in-house Long Evans breeding colony.
- Age at study initiation: (P) x 15-16 wks; (F1) x 3 wks
- Weight at study initiation (means): Females approximately 240 g. Males not weighed.
- Fasting period before study: No
- Housing: Individually in elevated stainless steel cages.
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: No data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%): No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 12.09. 1977 to 19.06.1978

Administration / exposure

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): Weekly
- Mixing appropriate amounts with (Type of food): Purina Laboratory Chow
- Storage temperature of food: No data

Details on mating procedure:

- M/F ratio per cage: 1:2
- Length of cohabitation: nightly until signs of mating.
- Proof of pregnancy: vaginal plug or sperm in vaginal smear referred to as day 0 of pregnancy.
- After successful mating each pregnant female was caged (how): Individually in elevated stainless steel cages.
- Any other deviations from standard protocol: Dosing not started until Day 0 of gestation.

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

Test substance administration to F0 females was initiated on gestation Day 0 and continued throughout gestation and lactation, and for F1males and females through the F2a and f2b litters.

Frequency of treatment:

Daily

Details on study schedule:

- F1 parental animals not mated until one week after selection from the F1 litters.
- Selection of parents from F1 generation when pups had reached maturity.

Doses / concentrations

Remarks:

Doses / Concentrations:
300, 1000 or 3000 ppm
Basis:
nominal in diet

No. of animals per sex per dose:

F0 females: 20.
F1 Parents: females - 20; males - 10.

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: No data
- Rationale for animal assignment (if not random): Random.
- F1 offspring were separated from siblings seven days after weaning of the last litter and were randomly selected to continue as future parents (f1). More offspring than needed were selected (12 males and 24 females) for the growth period to insure the required number of adults (10 males and 20 females) necessary for mating. Following pup selection, remaining offspring and F0 females were sacrificed and discarded after gross external and internal examinations.
F1 animals were raised to maturity and mated to produce the F2a litters. F2a pups were sacrificed, necropsied and discarded at weaning. All F1 females were remated after a rest period of at least 14 days to produce the F2b litters. F2b pups were sacrificed and necropsied at weaning. Following completion of the F2b sacrifice, all F1 parents were sacrificed, necropsied and selected tissues preserved.

Positive control:

None

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: mortality and gross signs of toxicity in F0 and F1: twice daily.


DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Weekly (F0 and F1)


BODY WEIGHT: Yes
- Time schedule for examinations: Males and nonpregnant females (F1): weekly in growth and rest periods of F1 generation. Pregnant females (F0 and F1): Days 0, 6, 15 and 20 of gestation. Lactation females (F0 and F1): Days 0, 4, 14 and 21 of lactation.


FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
-Males and nonpregnant females: weekly for growth and rest periods of F1 generation.
-Test substance consumption was calculated from body weight and food consumption values: Males and nonpregnant females: weekly during growth and rest periods of F1 generation.


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

Oestrous cyclicity (parental animals):

Not examined as dosing in F0 dams started on Day 0 gestation, F0 males not dosed.

Sperm parameters (parental animals):

Parameters examined in [all/P/F1/F2] male parental generations: No data

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes

PARAMETERS EXAMINED:
Gestation period: On day 19 of gestation, dams were provided with nesting material and were examined daily for signs of parturition.
Lactation period (Day 0 is day on which all pups had been delivered): General appearance of pups and presence of dead pups examined daily in all litters (F1, F2a and F2b). LIve, dead and missing pups were recorded on Days 0, 1, 4 (pre-cull and post-cull), 14 and 21 of lactation in all litters (F1, F2a and F2b). Live pups were weighed as a litter on Days 0, 4 (pre-cull) and 21 (calculated from individual weights) of lactation for all litters, and individually on Day 21 of lactation for all litters.
Litter Data and Observations: The number of each sex per litter was determined on Days 0 and 4 (pre- and post-cull) of lactation for all litters. Individual sex determination on Day 21 of lactation for all litters.

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

Postmortem examinations (parental animals):

SACRIFICE
F0 generation: All females sacrificed after weaning of F1 offspring, and necropsy performed.
F1 generation: All surviving males and females sacrificed after weaning and necropsy of the last F2b litter. Necropsy performed, and selected organs weighed and tissues preserved.
Extra F1 males and females: sacrifice at initiation of mating, necropsy performed and discarded.
Dead and moribund dams: Necropsy performed. Uterine contents examined and presence of implantation sites and/or scars recorded.

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


HISTOPATHOLOGY / ORGAN WEIGHTS
The tissues indicated in Table 1 were weighed and/or prepared for microscopic examination.

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring not selected as parental animals and all F2 offspring were sacrificed after weaning. Necropsy performed including internal sex determination peformed, then carcassed discarded.
- F2a: necrospy included internal sex determination performed. All offspring where then discarded.
- F2b: necrospy included internal sex determination performed. Selected tissues were preserved from ten randomly chosen males and females from all groups.
F2b found dead after Day 14 of lactation: necropsy including internal sex determination performed and discarded.
Culled F1, F2a and F2b: sacrifice on Day 4 of lactation. Necropsy including internal sex determination performed and discarded.


GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations including the cervical, thoracic, and abdominal viscera.
- Dead pups: sex was determined and pups checked for presence of milk in their stomach and discarded.


HISTOPATHOLOGY / ORGAN WEIGTHS
The tissues indicated in Table 1 were preserved for F2b offspring.

Statistics:

Body weight, body weight gain, food consumption and litter examination data, organ weights, organ/body weight and organ/brain weight ratios were analysed. Group I and Group II (control groups) were compared to each other. If no statistically significant differences, the control groups were combined and compared against test groups. If controls differed, individual control/test comparisons conducted - continuous and discrete data (body weight, food intake, organ weight): Dunnett's test.  - gestation length: F-test and Student's T-test (Cochran's approximation). - offspring data: Chi-square. Incidence data for control Group II was compared to control Group I and incidence data for each test substance treated group was compared to each control group.

Reproductive indices:

F0 females: Pregnancy rates, gestation length, percentage of mothers that weaned litters.
F1 females: Mating and fertility indices, pregnancy rates, parturition indices, gestation length, percentage of mothers that weaned litters.

Offspring viability indices:

F1 litters: Mean numbers of live and dead pups at birth, pup survival (at representative intervals through lactation), body w eight, sex distribution.
F2 litters: Mean numbers of live and dead pups at birth, pup survival (at representative intervals through lactation), body w eight, sex distribution.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

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)

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS): No parental animals died or showed clinical signs of toxicity.


BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS): There were no effects on body weight/body weight gain.


TEST SUBSTANCE INTAKE (PARENTAL ANIMALS): There are no comments on this, but as food consumption was not affected, test substance intake should also have not been affected.


REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS): No effects. A statistically significant reduction in mean gestation length for F2a animals from the 1000 ppm group (22.1 d) versus the pooled F2a controls (22.4 d) was considered spurious by the authors. Also, the lower pregnancy rate recorded in the F1/F2a mating (not significant) was not replicated in the second mating (F1/2b).


ORGAN WEIGHTS (PARENTAL ANIMALS): No effects found.


GROSS PATHOLOGY (PARENTAL ANIMALS): No abnormal findings.


HISTOPATHOLOGY (PARENTAL ANIMALS): No abnormal findings.

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

3 000 ppm

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Details on results (F1)

VIABILITY (OFFSPRING): The mean numbers of live and dead pups at birth (F1) were considered comparable between the controls and 300 and 1000 ppm groups. In the high dose group there was a decrease in the mean numbers of live pups with a corresponding increase in the mean number of dead pups observed at birth. The differences were not statistically significant compared with the combined control values. The 24 hour and four day survival indices for the treated groups were slightly lower than the control values, and some statistically significant differences from a control group were observed. There was no dose-response relationship so it was concluded that the difference were not treatment-related. There was a slight increase in the mean number of dead pups at birth in the F2a litters at the high dose. However, the increase was attributed to one female that had five dead pups. Pup survival indices were comparable between the groups for the F2 generation.


CLINICAL SIGNS (OFFSPRING): There were no clinical signs of toxicity.


BODY WEIGHT (OFFSPRING): In the highest dose group (F1) there was a non-statistically significant reduction in mean pup weights at birth. There was a slightly lower pup birth weight in mid and high dose groups, but the difference was only statistically significant in the highest dose group compared with the combined controls. There was no difference at other time points or in the F2b generation.


GROSS PATHOLOGY (OFFSPRING): No abnormal findings.

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1 000 ppm

Results: F2 generation

Effect levels (F2)

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

1 000 ppm

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Table 2 Summary of Gestation length, litter survival, growth of offspring and weaning sex ratio data.

Group (ppm)	Mean gestation period (days)	Mean No.		Mean No. weaned/litter	Litters weaned		Mean live offspring weights (g)				Day 21 sex ratio (M/F)
		Live	Dead		No	%	Day 0	Day 4^a	Day 14	Day 21	No.	Ratio^b
F0 to F1
I/0	22.1	12.3	0.1	9.8	18/18	100	5.9	9.4	27.3	40.8	86/90	0.96
II/0	22.1	11	0.6	8.9	17/18	94.4	5.9	9.3	27.0	41.5	71/81	0.88
I+II	22.1	11.6	0.3	9.4			5.9	9.3	27.2	41.1
III/300	21.9	11.3	0.8	9.5	17/18	94.4	5.9	9.6	27.9	41.3	81/81	1.00
IV/1000	21.9	10.9	0.6	8.7	17/17	100	6.1	9.8	27.3	40.4	65/83	0.78
V/3000	22.3	9.2	1.9	7.9	17/19	89.5	5.7	8.5	26.6	40.8	64/70	0.91
F1 to F2a
I/0	22.4	10.9	0.1	8.7	13/14	92.9	6.3	9.7	26.6	35.4	55/58	0.95
II/0	22.4	10.5	0.3	9.1	14/15	93.3	6.1	10.1	25.5	35.3	64/63	1.02
I+II	22.4	10.7	0.2	8.9			6.2	9.9	26.0	35.3
III/300	22.3	12.4^#	0.1	9.3	17/18	94.4	6.2	9.3	26.0	36.4	83/75	1.11
IV/1000	22.1^#	11.1	0.0	8.8	19/19	100	5.8	9.2	24.8	34.7	84/84	1.00
V/3000	22.2	11.7	0.8	9.5	13/13	100	5.8^#	9.2	25.6	34.6	60/63	0.95
F1 to F2b
I/0	22.3	12.3	0.1	8.9	14/15	93.3	6.0	8.8	26.1	39.2^+	59/66	0.89
II/0	22.1	9.4	0.9	7.8	15/17	88.2	6.1	9.7	29.5	45.0*	61/56	1.09
I+II	22.2	10.8	0.6	8.3			6.0	9.3	27.8
III/300	22.1	12.5	0.3	9.3	19/19	100	6.1	9.5	27.6	41.3	83/93	0.89
IV/1000	22.1	11.4	0.9	9.3	15/17	88.2	5.8	9.0	26.5	39.5 ^++	75/73	1.03
V/3000	22.2	11.1	0.5	9.2	14/15	93.3	5.9	9.3	27.2	40.1	63/66	0.95

Significantly different from control Group I: *p≤0.05; **p≤0.01.

Significantly different from control Group II: +p ≤0.05; ++p ≤0.01.

Significantly different from pooled values of control Groups I and II: #p ≤0.05; ##p ≤0.01.

a Pre-cull weight only.

b Data not analysed statistically.

Applicant's summary and conclusion

Conclusions:

In a well conducted and documented, pre-GLP one generation reproductive toxicity study (reliability score 2), CP 66257 (DTPMP) administered via the diet caused no clear treatment-related or statistically significant effects in rats. Pregnancy rate and pup body weight were lower for F2a litters from dams fed diets containing 3000 ppm DTPMP, but this was not replicated in the F1 or F2b litters. A NOAEL of 294 mg/kg bw/d for males and 312 mg/kg bw/d in females was therefore concluded.

Executive summary:

In a well conducted and documented, pre-GLP one generation reproductive toxicity study (reliability score 2), CP 66257 (DTPMP) was administered continuously via the diet to Long-Evans rats at concentrations of 300, 1000 and 3000 ppm through one complete generation. Test substance administration to the F0 generation females (20/group) was initiated at the onset of gestation and continued throughout the ensuing gestation and lactation periods. Administration then continued to the F1 generation animals (10 males and 20 females/group) through a growth period and mating, gestation and lactation period for two successive litters. Parameters evaluated included parental mortality, mating-fertility indices, body weight and food consumption data, necropsy observations and organ weight data (absolute and relative) for the F1 parental generation. Litter parameters included gestation length, pup viability at birth and litter survival indices. Pups were evaluated for survival, growth and necropsy observations at weaning.

In the F0 generation, no treatment-related effects in the low and mid dose groups were evident. In the high dose group, females delivered litters containing fewer live pups and more dead pups (not statistically significant). Pups also had a lower weight at birth (

not statistically significant). No other treatment-related effects were observed. In the F1 generation, no treatment-related effects were evident in the low dose group. In the mid dose group, pup weight at birth was lower than control in the first litters (F2a) only. No such effects were observed in the second litters and no other treatment-related effects were observed during the remainder of the study. Gross pathological examination of five adult F1 generation males and females of the control and high dose groups did not reveal any abnormal findings. A NOAEL of 294 mg/kg bw/d for males and 312 mg/kg bw/d in females was therefore concluded.