Pentapotassium triphosphate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Reference

Endpoint:

three-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

No data.

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Study not performed to GLP or guideline. But has been reviewed by an expert assessor (see expert report attached) and determined to be suitable for use for the purposes of REACH registration. See overall remarks for further discussion on deficiencies. 1. Only one dose level was included in the study. 2. Test material was not analyzed in diet. No impurity profile of test material was provided. 3. The group size was smaller than the 20 females and 10 males required in OECD guideline 416. 4. Only one dose level was tested with a control group. 5. There was no recorded acclimation period for the P generation. 6. Daily observations of parents and observations of abnormal behaviour of offspring are not reported. 7. Body weights: Parental body weights were not recorded during gestation and lactation. 8. Food consumption was not determined. 9. Estrous cycle was not evaluated. 10. Sperm parameters were not included. 11. Offspring sex and sex ratios were not determined. Litter body weight was reported; however, individual pup body weights were not recorded. 12. There is no report of gross pathology and necropsy observations. 13. Organ weight data for the uterus, epididymides (total and caudal), prostate, seminal vesicles with coagulating gland, pituitary gland, adrenals and thyroid gland were not included. 14. Histopathology was conducted only on the F3b offspring and did not include the following organs: uterus, cervix, vagina, epididymides, seminal vesicles, prostate, coagulating gland, pituitary gland. Note that the known target organ (kidney) was evaluated. 15. Statistics are not reported.

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See read-across justification report under Section 13 ‘Assessment Reports’.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
In accordance with REACH Annex XI, Section 1.5, of Regulation (EC) No. 1907/2006 (REACH) the standard testing regime may be adapted in cases where a grouping or read-across approach has been applied.

The similarities may be based on:
(1) a common functional group
(2) the common precursors and/or the likelihood of common breakdown products via physical or biological processes, which result in structurally similar chemicals; or
(3) a constant pattern in the changing of the potency of the properties across the category

1. Both substances are inorganic salts of a monovalent cation from Group 1A of the periodic table, and triphosphoric acid. Thus, they share the Na+ or K+ cation and P3O105- anion.
2. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity.
3. In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across. Therefore it is not considered to be scientifically justified to perform any further in vivo studies.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See read-across justification report under Section 13 ‘Assessment Reports’.

3. ANALOGUE APPROACH JUSTIFICATION
See read-across justification report under Section 13 ‘Assessment Reports’.

4. DATA MATRIX
See read-across justification report under Section 13 ‘Assessment Reports’.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

no guideline followed

Principles of method if other than guideline:

A reproduction study spanning three generations of rats reared and maintained on diets containing 0.0% and 0.5% pentasodium triphosphate (STPP). Per generation two different litters were bred; one was sacrificed and the other was bred to produce the next generation. Matings were carried out between 16 females and 8 males in each group when the rats were 100 days old. Observations were limited to: the number of pups born, pup mortality up to 21 days, organ weights and histopathological changes in the tissues and organs.

GLP compliance:

no

Remarks:

Study predates GLP

Limit test:

no

Species:

rat

Strain:

other: Rochester Strain (Ex-Wistar 1923)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation:
The parental generation were mated when they were 100 days old. Succeeding generations were also mated at 100 days of age.
- Weight at study initiation: 60g
- Housing: Galvanized iron cages with screen wire doors. The bottoms of the cages were pans filled with wood
shavings.
- Diet: e.g. ad libitum
- Water :e.g. ad libitum


ENVIRONMENTAL CONDITIONS
- no data

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
Diets were prepared at weekly intervals by mixing, using a mechanical mixer, the appropriate amounts of STPP as needed into the control ration. Diet mixtures were stored in galvanized iron buckets with covers.

Details on mating procedure:

- M/F ratio per cage: 1 male:2 female
- Length of cohabitation: 7 days.
- Proof of pregnancy: no data.
- Unsuccessful pairing replacement of first male by another male with proven fertility - no.
- Further matings after two unsuccessful attempts: no data.
- After successful mating each pregnant female was caged (how): no data.
- other: As there were two matings per generation the males were rotated so that at each mating a different male would be placed in the cage with the females.

Sixteen females and 8 males will be mated at 100 days of age from each of the above 2 groups (controls and 0.5% tripolyphosphate). They will be mated again 10 days after weaning of the first litter. Sixteen females and 8 males from the second litters will be selected from each group at weaning and continued on their respective diets. When 100 days old they will be mated; then mated again 10 days after weaning the first litter. This procedure will be
repeated with the rats to produce a second litter of the third generation.

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

Not applicable.

Duration of treatment / exposure:

Exposure took place:
- for 100 days prior to mating
- 21 days of gestation
- during lactation (the P1, F1b and F2b)
- the F3b were exposed for their first 21 days after which time they were sacrificed.
- Following weaning of the F1b litter, 8 males and 16 females for the control group and the treated group were fed their respective diets for 100 days. 
Litters were culled to 10 pups with approximately 5/sex/group on postnatal day 5.

Frequency of treatment:

Daily in diet (ad libitum).

Details on study schedule:

See table 1 for details on the study schedule.

Remarks:

Doses / Concentrations:
0.5% in diet
Basis:
nominal in diet

No. of animals per sex per dose:

P1, F1, F2, F3: 16 females and 8 males

Control animals:

yes, concurrent no treatment

Details on study design:

- Dose selection rationale: 0.05% and 0.5% diets were considered. After 100 days the 0.5% group exhibited no depression of bodyweight and was selected for use in the reproduction study.
- Other: The first litters born, the F1a,2a,3a were sacrificed. The second litters, F1b,2b were mated to produce the next generation.

Positive control:

There was no positive control.

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: No data

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations: Body weights were measured weekly during the 100 day pre-mating exposure for each generation.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): No

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

Oestrous cyclicity (parental animals):

Not evaluated.

Sperm parameters (parental animals):

Not evaluated.

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 5 postpartum: [yes]
- excess pups were sacrificed to leave 10 per litter.

PARAMETERS EXAMINED
The following parameters were examined in [F1 / F2 / F3] offspring:
number of pups, pups/litter, pup mortality up to 21 days of age, weight gain per litter.

GROSS EXAMINATION OF DEAD PUPS: No
NOT EVALUATED: sex of pups, presence of gross anomalies, physical or behavioural abnormalities, no individual pup body weights

Postmortem examinations (parental animals):

SACRIFICE
- The F1a,2a,3a were sacrificed at 30 days postpartum.
- No data on parental fate after the mating and weaning.

GROSS NECROPSY
- no data.

HISTOPATHOLOGY / ORGAN WEIGHTS
Not performed for parental rats.

Postmortem examinations (offspring):

SACRIFICE
- The non-parental litters, F1a , F2a , F3a , and F3b were sacrificed after 30 days.
- Observations amongst these litters were limited to litter weights on the 21st day.
- In the F3b histopathological and organ weight examinations were performed.

GROSS NECROPSY
F3b examined only.

HISTOPATHOLOGY / ORGAN WEIGTHS - The ten males and ten females from final litter, the F3b litter, were evaluated for body weight, histopathology.
- Histopatholigcal examinations performed for: Liver, kidneys, gonads, lungs, brain, stomach, heart, spleen, adrenal, stomach, large and small intestines, bladder, lymph nodes, gut, marrow, pancreas)
- Organ weights recorded for: Liver, kidneys, testes, lungs, brain, stomach, heart, spleen.
- Organ weights not recorded for: Uterus, ovaries, epididymides (total and cauda), prostate, seminal vesicles, pituitary, thyroid, adrenal glands.
- Histopathological examinations not performed for: Vagina, uterus with cervix, epididymis, seminal vesicle, prostate coagulating gland.

Clinical signs:

not specified

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

not examined

Other effects:

not examined

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Description (incidence and severity):

based on equivalent numbers of pups born and surviving weaning in the controls and treated groups.

See table 2 (attached document - "reproductive performance") for a comparison of the control and treated groups's reproductive performance.

Key result

Dose descriptor:

NOAEL

Effect level:

250 mg/kg bw/day

Based on:

test mat.

Remarks:

test material in diet.

Sex:

male/female

Basis for effect level:

other: No effects observed

Key result

Dose descriptor:

NOAEL

Effect level:

0.5 other: % in diet

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects noted

Key result

Critical effects observed:

no

Clinical signs:

not examined

Mortality / viability:

no mortality observed

Description (incidence and severity):

See table 2 (attached)

Body weight and weight changes:

no effects observed

Description (incidence and severity):

See Table 2 (attached)

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

- See Table 2 (attached.) for details on viability and bodyweights.
The attached graphs highlight the similiarity in growth rates between control and treated groups for the F1b and F2b.

- For Organ weights see Table 3 (attached). Treated and control groups were considered to be comparable for all organs weighed.
Inspection shows nearly identical average weights, both fresh weights and on basis of body weights. For both the male and the female rats, the average kidney weights (basis body weight) are slightly greater for the rats maintained on the 0.5% TPP diets than on the control diets. These differences, however, are not statistically significant.

- There were no treatment-related histopathological findings.

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

250 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

0.5 other: % in diet

Based on:

test mat.

Sex:

male/female

Remarks on result:

other: no effects noted

Key result

Critical effects observed:

no

Clinical signs:

not examined

Body weight and weight changes:

no effects observed

Key result

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

250 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects noted

Key result

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

0.5 other: % in diet

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects noted

Key result

Critical effects observed:

no

Key result

Reproductive effects observed:

no

This study included only one dose level of the test material, 0.5% in the diet. There were occasional fluctuations in the fertility index.  The lower fertility index in the F2a, F3a and F3b litters is considered spurious and not treatment-related.  The fertility indices of the treated group were greater than the control group for some litters (F1a, F2b); the same as the control group for the F1b litter, and less than the control group for other litters (F2a, F3a, F3b).  These variations are not considered to show a treatment-related effect on fertility.  The duration of pregnancy, live birth index, litter size, litter weights, survival index, viability index and lactation index were all comparable between control and treated groups.  Organ weights were similar between control and treated groups.  There were no treatment-related histopathological findings.

Parameter			Control		High dose
		Generation	M	F	M	F
Mortality	Incidence	P	0	0	0	0
		F1	0	0	0	0
		F2	0	0	0	0
		F3	0	0	0	0
Food consumption	% of control		NA	NA	NA	NA
Body weight gain	% of control		100	100	100	100
Clinical Observations specify effects	Incidence		NA	NA	NA	NA
Organ weights (F3b)	% of control		95 -103	95 -103	95 -103	95 -103
Pathology
Histopathologic examination: F3b Immature testes Renal cyst Parasites in intestine Focal pulmonary hemorrhage Parasites in renal pelvis	Incidence		10 - - - -	- - 1 1 -	10 1 1 1 -	- - - - 2
Reproductive Performance
Mating index: P			-	NA		NA
F1			-	NA	-	NA
F2			-	NA	-	NA
F3			-	NA	-	NA
Fertility index: P, la			-	87.5	-	93.8
F1b			-	75	-	75
F2a			-	82.3	-	68.8
F2b			-	76.5	-	81.3
F3a				81.3	-	68.8
F3b				80	-	62.5
Number of implantation sites	Mean		-	NA	-	NA
Duration of pregnancy: P, 1a	Mean days			24.7		24.06
F1b				25.1	-	25.25
F2a				23.36	-	24.91
F2b				25	-	24.4
F3a				25.8	-	25.1
F3b				25.2	-	25
Birth index
Live birth index: P, 1a			-	93.8	-	100
F1b				93.8	-	100
F2a				100	-	100
F2b				100	-	93.8
F3a				93.8	-	100
F3b				100		87.5
Gestation index
Litter size: P, 1a	Mean		-	8.9	-	9.2
F1b				11	-	13
F2a				9.2	-	9.5
F2b				10.7	-	10.2
F3a				10.4	-	10.2
F3b				8.4	-	10.5
Litter weight: P, 1a	Mean, day 21, g		-	307	-	283
F1b				348	-	392
F2a				279	-	341
F2b				379	-	325
F3a				270		349
F3b				319	-	388
Pup weight, 1a	Mean: day 21, g			36.8	-	37.8
F1b				42.2	-	40.5
F2a				42.9	-	42.1
F2b				40.3	-	41.5
F3a				41.4	-	43.7
F3b				45.6	-	41.9
Sex ratio	Male/female			NA		NA
Survival index: P, 1a	Day 5			91.4	-	95.6
F1b				91.6	-	97.4
F2a				93.3	-	88.6
F2b				96.7	-	93.4
F3a				82.4	-	85.2
F3b				74.8	-	98.8
Viability index: P, 1a	Day 21		-	86.2	-	81.1
F1b				75	-	74.3
F2a				74.2	-	84.8
F2b				85	-	77
F3a				72.8	-	72
F3b				76.2	-	88
Lactation index: P, 1a	Day 21			86.2	-	81.1
F1b				75	-	74.3
F2a				74.2	-	84.8
F2b				85	-	77
F3a				72.8	-	72
F3b				76.2	-	88
Sperm characterization				NA		NA
Number	% of control			NA		NA
Deformations	% of control			NA		NA

Conclusions:

Three generations of rats reared and maintained on diets containing 0.5% STPP showed no adverse effects to the test material - Control and test data were comparable across the range of observations made. Observations were limited to reproductive performance, pup mortality, organ weights and tissue and organ histopathology. Based on this evidence sodium metaphosphate is not considered to be classified as a reproductive toxicant according to Regulation (EC) 1272/2008 (EU CLP).

Although this study is limited and deficient by modern standards, it is still possible to make some valid scientific conclusions from the data. Adequate data are reported to show no effects on fertility or reproductive performance or on offspring growth and development over three generations with two litters per generation. Thus, the study should be considered acceptable for the dose level tested, 0.5% test material in the diet.

Effect on fertility: via oral route

Dose descriptor:

NOAEL

225 mg/kg bw/day

Additional information

Read across argument

Both substances are ionic inorganic compounds containing a triphosphate anion and a group 1 alkali metal cation. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity.

In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across.

Therefore it is not considered to be scientifically justified to perform any further in vivo studies.

Assessment of the key study

The Hodge reproduction study (1960) was conducted prior to the institution of good laboratory practice guidelines and to the current OECD Guideline 416. Therefore, the study has deficiencies when examined according to today’s standards. The study is considered a Klimisch Code 2, reliable with restrictions. The conclusions regarding the hazard identification of STPP are supported by data on sodium hexametaphosphate (SHMP) and sodium trimetaphosphate (STMP), both of which are structurally similar to STPP. All three inorganic phosphate salts had no adverse effects on reproductive toxicity and fertility when tested in rats over three generations (Hodge 1959, 1960). 

In the Manual for Investigation of HPV Chemicals, Chapter 3: Data Evaluation (2005), Section 3.1.6 Weight-of-the-Evidence Analysis, requires the use of a weight-of-the-evidence analysis during the assessment of data quality and adequacy.  The guidance permits the pooling of several studies, one or more of which may be inadequate, to satisfy a specific SIDS element. In the current case, available data exist on two other sodium inorganic phosphate salts which are similar in structure to STPP.  Three generation reproduction studies have been conducted on SHMP and STMP which are similar to the one on STPP in that they were conducted prior to good laboratory practice guidelines and the existence of OECD Guideline 416; nevertheless, they provide additional supplemental support for the hazard assessment of STPP (IUCLID Robust Study Summary included as supplemental information). Because all three sodium phosphates showed no effects on reproductive performance, these data show similar responses which allows a more robust conclusion for the individual salts. STPP and SHMP were both tested at a dose level of 0.5% in the diet. STMP was tested at a dose of 0.05% in the diet. These dose levels were viewed as appropriate levels based on the results of the chronic toxicity/carcinogenicity studies for each salt.

Short description of key information:
Regulation EC 1907/2006 - Annex VIII - Section 8.7.1. Screening for reproductive toxicity.

Screening for reproductive toxicity does not need to be conducted if a study is available for a two-generation reproductive toxicity study (Annex IX, Section 8.7.3). An Annex IX 8.7.3 study can be found in section 7.8.1 of this dossier.


Regulation EC 1907/2006 - Annex VIII - Section 8.7.3. Two generation reproductive toxicity study.

The Hodge reproduction study (1960) was conducted with analagous substance pentasodium triphosphate, but is considered suitable for the assessment of pentapotassium triphosphate for the reasons described in the discussion below.
Three generations of rats were reared whilst being exposed to the test material. Parents were fed diets containing 0.5% pentasodium triphosphate during the 100 days prior to mating, during the 21 days of gestation and during lactation (where applicable). This exposure pattern was repeated for the next generation of rats following weaning. There were two litters per generation, the second litter FXb parented the following generation. The F3b were the final generation and were exposed for their first 21days after which time they were sacrificed.
Observations were limited to body weight, histopathology (liver, kidneys, gonads, lungs, brain, stomach, heart, spleen, adrenal, stomach, large and small intestines, bladder, lymph nodes, gut, marrow, pancreas) and organ weights (liver, kidneys, testes, lungs, brain, stomach, heart, spleen).
The study was conducted before the institution of GLP and the modern standard test Guideline OECD 416. This result provides evidence for the assumption that there is no concern with regard to effects of pentasodium triphosphate on reproduction.
Supplemental evidence for the assessment is provided - similar reproduction studies are summarised for SHMP (sodium hexametaphosphate) and STMP (sodium trimetaphosphate).

Effects on developmental toxicity

Description of key information

Regulation EC 1907/2006 - Annex VIII - Section 8.7.1. Screening for developmental toxicity.
Screening for developemental toxicity does not need to be conducted if a pre natal developmental toxicity study is available (Annex IX, Section 8.7.3). An Annex IX 8.7.3 study can be found in section 7.8.1 of this dossier.
Section 8.7.2, Prenatal developmental toxicity.
Studies are available for the analogous substance pentasodium triphosphate (STPP) which is considered to be suitable for the assessment of pentapotassium triphosphate (KTPP) for the reasons discussed below. 
Four prenatal developmental toxicity studies (Morgareidge K 1973) were performed by the US food and drug administration. The tests were conducted before the instituation of GLP but are comparable to modern guideline OECD 414. The test material was not found to be a teratogen when tested on rats, mice, rabbits and hamsters.

Link to relevant study records

Reference

Reference 1

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Comparable to OECD guideline 414 with acceptable restrictions. 1. There were not 20 female animals with implantation sites at necropsy in each dose group as described in OECD414. 2. Dosing was carried out from day 6-18, OECD 414 recommends from day 5-28 (the day prior to caesarean section) 3. No data on assessment of gravid uteri.

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See read-across justification report under Section 13 ‘Assessment Reports’.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
In accordance with REACH Annex XI, Section 1.5, of Regulation (EC) No. 1907/2006 (REACH) the standard testing regime may be adapted in cases where a grouping or read-across approach has been applied.

The similarities may be based on:
(1) a common functional group
(2) the common precursors and/or the likelihood of common breakdown products via physical or biological processes, which result in structurally similar chemicals; or
(3) a constant pattern in the changing of the potency of the properties across the category

1. Both substances are inorganic salts of a monovalent cation from Group 1A of the periodic table, and triphosphoric acid. Thus, they share the Na+ or K+ cation and P3O105- anion.
2. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity.
3. In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across. Therefore it is not considered to be scientifically justified to perform any further in vivo studies.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See read-across justification report under Section 13 ‘Assessment Reports’.

3. ANALOGUE APPROACH JUSTIFICATION
See read-across justification report under Section 13 ‘Assessment Reports’.

4. DATA MATRIX
See read-across justification report under Section 13 ‘Assessment Reports’.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

1. There were not 20 female animals with implantation sites at necropsy in each dose group as described in OECD414. 2. Dosing was carried out from day 6-18, OECD 414 recommends from day 5-28 (the day prior to caesarean section) 3. No data on assessment of gravid uteri.

Deviations:

yes

Remarks:

See remarks

GLP compliance:

not specified

Limit test:

no

Species:

rabbit

Strain:

Dutch

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Housing: mesh bottom cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENT
- The animals were housed in temperature and humidty controlled rooms.

Route of administration:

oral: gavage

Vehicle:

water

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

Not applicable.

Details on mating procedure:

- On day 0 the doe's pretreated with human chorionic gonadotrophin were, 3h later, artificially inseminated with sperm from proven buck.

Duration of treatment / exposure:

On day 6 and continuing through to day 18 the females were dosed with the test material.

Frequency of treatment:

Daily through treatment period.

Duration of test:

13 days of treatment.

No. of animals per sex per dose:

15 - sham treated control; 13 - positive control; 16 - 2.5 mg/kg; 15 - 11.6 mg/kg; 16 - 54 mg/kg; 13 - 250 mg/kg.

Control animals:

yes, concurrent vehicle

other: Positive control fed 2.5 mg/kg of 6-aminonicotinamide, dosed on day 9

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes, for appearance and behaviour.
- Time schedule: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 6, 12, 18 and 29 of gestation

POST-MORTEM EXAMINATIONS: No data

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
Food consumption was monitored to rule out abnormalities as a result of anorexic effects.

Ovaries and uterine content:

The urogenital tract of each animal was examined.
(and included:)
- Gravid uterus weight: No data
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of resorptions: Yes

Fetal examinations:

- External examinations: Yes: gross examination - all per litter
- Pup survival - Following caesarean section the pups were placed in an incubator for 24 hours to assess neonatal survival.

The pups were then sacrificed and examined as follows:

- visceral exminations.
- Soft tissue examinations: Yes: all per litter
- Skeletal examinations: Yes: all per litter
- Head examinations: No data
- Bodyweight of live pups also recorded.

Statistics:

No data

Indices:

No data.

Details on maternal toxic effects:

Maternal toxic effects:no effects. Remark: please see below.

Details on maternal toxic effects:
Cage-side observations and periodic recording of bodyweight suggested no signs of toxicity. There were no discernible effects on nidation.

Dose descriptor:

NOEC

Effect level:

250 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: no effects observed

Abnormalities:

no effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
The number of abnormalities seen in either soft or skeletal tissues of the test group did not differ from the number occurring spontaneously in the sham treated control.

Dose descriptor:

NOEC

Effect level:

250 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No effects observed

Abnormalities:

no effects observed

Developmental effects observed:

no

Table 1 - Reproduction data

Dose (mg/kg)	0	Positive control*	2.5	11.6	54	250
Pregnancy
Total no	15	13	16	15	16	13
Died or aborted	5	2	1	3	8	1
To term	10	11	15	12	14	12
Total corpora lutea	216	166	227	242	263	200
Average corpora lutea	10.8	9.76	11.4	12.1	12.0	9.52
Total live litters	8	8	14	12	14	10
Average implant site no	6.20	4.91	5.13	6.08	5.71	5.33
Resorptions
Percent partial resorptions	50.0	72.7	26.7	16.7	50.0	50.0
Percent complete resorptions	10.0	27.3	6.67	-	-	16.7
Average live foetus	4.7	3.73	4.27	5.42	5.07	4.42
Sex ratio (m/f)	1.35	1.16	1.29	1.16	1.29	0.83
Dead foetuses	6	1	4	-	1	-
Percent partial dead	10.0	9.09	13.3	-	7.14	-
percent all dead	10.0	-	-	-	-	-
Average foetus weight (g)	37.2	33.5	41.8	39.7	41.0	38.9

*2.5 mg/kg 6-aminonicotinamide dosed on day 9

Table 2 - Summary of skeletal findings

Dose (mg/kg)	0	Positive control	2.5	11.6	54.0	250
Sternebrae
Incomplete oss	-	6/2	-	-	4/3	-
Bipartite	-	-	-	-	1/1	-
Fused	-	10/5	6/3	1/1	2/2	1/1
Extra	2/2	1/1	-	2/2	3/3	2/1
missing	-	1/1	-	-	1/1	-
Ribs
Fused/split	-	13/6	-	-	-	-
Vertebrae
Scrambled	-	16/6	-	-	-	-
Scoliosis	-	13/6	-	-	-	-
Tail defects	1/1	35/8	-	-	1/1	-
Skull
Incomplete closure	-	1/1	-	-	-	-

(number of foetuses effected/number of litters)

Soft tissue abnormalities were only observed in the positive control group.

Conclusions:

Under the conditions of the study, the test material administered to pregnant rabbits for 13 days up to a dose level of 250 mg/kg bw showed no maternal or developmental toxicity. The NOAEL for both maternal and fetoxicity is > 250 mg/kg bw. The number of abnormalities seen in either soft or skeletal tissues of the test groups did not differ from the number occurring spontaneously in the sham treated controls.

This study is considered to be of adequate reliability and relevance to be submitted as the key study for this endpoint.

Reference 2

Endpoint:

developmental toxicity

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Comparable to OECD guideline 414 with acceptable restrictions. 1. The study is performed in mice, not rats or rabbits as suggested in OECD 414. 2. No data on assessment of gravid uteri.

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See read-across justification report under Section 13 ‘Assessment Reports’.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
In accordance with REACH Annex XI, Section 1.5, of Regulation (EC) No. 1907/2006 (REACH) the standard testing regime may be adapted in cases where a grouping or read-across approach has been applied.

The similarities may be based on:
(1) a common functional group
(2) the common precursors and/or the likelihood of common breakdown products via physical or biological processes, which result in structurally similar chemicals; or
(3) a constant pattern in the changing of the potency of the properties across the category

1. Both substances are inorganic salts of a monovalent cation from Group 1A of the periodic table, and triphosphoric acid. Thus, they share the Na+ or K+ cation and P3O105- anion.
2. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity.
3. In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across. Therefore it is not considered to be scientifically justified to perform any further in vivo studies.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See read-across justification report under Section 13 ‘Assessment Reports’.

3. ANALOGUE APPROACH JUSTIFICATION
See read-across justification report under Section 13 ‘Assessment Reports’.

4. DATA MATRIX
See read-across justification report under Section 13 ‘Assessment Reports’.

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

1. The study is performed in mice, not rats or rabbits as suggested in OECD 414. 2. No data on assessment of gravid uteri.

GLP compliance:

not specified

Limit test:

no

Species:

mouse

Strain:

CD-1

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Housing: Disposable plastic housing
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
Temperature and humidity controlled environment.

Route of administration:

oral: gavage

Vehicle:

water

Analytical verification of doses or concentrations:

not specified

Details on mating procedure:

- Impregnation procedure: cohoused
- Proof of pregnancy: vaginal plug (vaginal plug considered as day 0 of gestation.)

Duration of treatment / exposure:

Day 6 through to 15 of gestation

Frequency of treatment:

Daily

Duration of test:

Treatment began on day 6 and ended on day 15, at day 17 the mice underwent caesarean section.

No. of animals per sex per dose:

22 - 2.4 mg/kg; 22 - 11.0 mg/kg; 23 - 52.0 mg/kg; 24 - 238.0 mg/kg; 21- sham treated; 22- positive control.

Control animals:

yes, sham-exposed

other: positive control, dosed with 250 mg/kg of aspirin.

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes, for appearance and behaviour
- Time schedule: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 6, 11, 15 and 17

POST-MORTEM EXAMINATIONS: No data
- Sacrifice on gestation day 17

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
Food consumption was monitored to rule out abnormalities of anorexic effects.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No data
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of resorptions: Yes

Fetal examinations:

- External examinations: Yes: gross examination - all per litter
- Soft tissue examinations: Yes: one third per litter
- Skeletal examinations: Yes: two thirds per litter
- Head examinations: Yes: two third per litter
- The bodyweights of live pups was also recorded.

Details on maternal toxic effects:

Maternal toxic effects:no effects. Remark: please see below.

Details on maternal toxic effects:
Cage-side observations and periodic recording of bodyweight suggested no signs of toxicity. There were no discernible effects on nidation.

Dose descriptor:

NOEC

Effect level:

238 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: no effects observed

Abnormalities:

no effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
The number of abnormalities seen in either soft or skeletal tissues of the test group did not differ from the number occurring spontaneously in the sham treated control group.

Dose descriptor:

NOEC

Effect level:

238 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No effects observed

Abnormalities:

no effects observed

Developmental effects observed:

no

Table 1 - Reproduction data

Dose (mg/kg)	Sham	Positive control*	2.4	11.0	52.0	238.0
Pregnancy
Total no	21	22	22	22	23	24
Died or aborted	0	1	0	0	0	0
To term	21	21	22	22	23	24
Total corpora lutea	315	419	308	373	397	414
Average corpora lutea	11.7	11.3	12.8	12.4	13.7	12.6
Total live litters	20	21	22	21	22	24
Average implant site no	11.0	11.7	12.3	11.0	12.5	11.8
Resorptions
Percent partial resorptions	38.1	52.4	40.9	54.5	43.5	29.2
Percent complete resorptions	-	-	-	4.55	-	-
Average live foetus	9.67	10.9	11.5	9.95	10.6	11.0
Sex ratio (m/f)	0.77	0.96	0.88	0.94	0.69	0.72
Dead foetuses	15	2	5	2	18	3
Percent partial dead	19.0	9.52	18.2	9.09	30.4	12.5
percent all dead	-	-	-	-	4.35	-
Average foetus weight (g)	0.89	0.88	0.81	0.83	0.76	0.77

*Aspirin 150.0 mg/kg

Table 2 - Summary of skeletal findings

Dose (mg/kg)	Sham	Positive control*	2.4	11.0	52.0	238.0
Sternebrae
Incomplete oss	83/18	54/15	124/22	45/14	81/19	113/23
Scrambled	1/1	-	-	-	-	-
Bipartite	5/4	3/3	1/1	6/3	7/6	3/2
Fused	-	-	-	-	1/1	-
Extra	1/1	-	1/1	-	-	1/1
missing	23/9	40/10	48/15	42/13	83/18	59/20
Ribs
More than 13	31/14	28/13	36/16	19/12	15/9	28/14
Vertebrae
Incomplete oss	1/1	19/6	15/8	19/7	18/8	12/5
Skull
Incomplete closure	-	-	-	-	1/1	-

(number of foetuses effected/number of litters)

No soft tissue abnormalities observed

Conclusions:

Under the conditions of the study, the test material administered to pregnant mice for 10 consecutive days up to a dose of 250 mg/kg bw showed no maternal or developmental toxicity. The NOAEL for both maternal and fetoxicity is >238 mg/kg bw. The number of abnormalities seen in either soft or skeletal tissues of the test group did not differ from the number occurring spontaneously in the sham treated control group.

This study is considered to be of adequate reliability and relevance to be submitted as the key study for this endpoint.

Reference 3

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Comparable to OECD guideline 414 with acceptable restrictions. 1. No data on assessment of gravid uteri.

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See read-across justification report under Section 13 ‘Assessment Reports’.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
In accordance with REACH Annex XI, Section 1.5, of Regulation (EC) No. 1907/2006 (REACH) the standard testing regime may be adapted in cases where a grouping or read-across approach has been applied.

The similarities may be based on:
(1) a common functional group
(2) the common precursors and/or the likelihood of common breakdown products via physical or biological processes, which result in structurally similar chemicals; or
(3) a constant pattern in the changing of the potency of the properties across the category

1. Both substances are inorganic salts of a monovalent cation from Group 1A of the periodic table, and triphosphoric acid. Thus, they share the Na+ or K+ cation and P3O105- anion.
2. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity.
3. In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across. Therefore it is not considered to be scientifically justified to perform any further in vivo studies.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See read-across justification report under Section 13 ‘Assessment Reports’.

3. ANALOGUE APPROACH JUSTIFICATION
See read-across justification report under Section 13 ‘Assessment Reports’.

4. DATA MATRIX
See read-across justification report under Section 13 ‘Assessment Reports’.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

1. No data on assessment of gravid uteri.

GLP compliance:

not specified

Limit test:

no

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Housing: mesh bottom cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
Temeprature and humidity controlled environment

Route of administration:

oral: gavage

Vehicle:

water

Analytical verification of doses or concentrations:

no

Details on mating procedure:

- Impregnation procedure: cohoused
- Proof of pregnancy: vaginal plug (vaginal plug considered as day 0 of gestation.)

Duration of treatment / exposure:

Day 6 through to 15 of gestation

Frequency of treatment:

Daily

Duration of test:

Treatment began on day 6 and ended on day 15, at day 20 the dams underwent caesarean section.

No. of animals per sex per dose:

22 - sham treated; 19 - positive control group; 22 - 1.7 mg/kg; 21 - 8.0 mg/kg; 23 - 37.0 mg/kg; 20 - 170.0 mg/kg.

Control animals:

yes, sham-exposed

other: positive control: 250 mg/kg Apirin.

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes, for appearance and behaviour.
- Time schedule: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 6, 11, 15 and 20

POST-MORTEM EXAMINATIONS: No data
- Sacrifice on gestation day 20

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
Food consumption was monitored to rule out abnormalities of anorexic effects.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: no data.
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of resorptions: Yes

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: one third per litter
- Skeletal examinations: Yes: two thirds per litter
- Head examinations: Yes: two third per litter
- The body weight of live pups was also recorded.

Details on maternal toxic effects:

Maternal toxic effects:no effects. Remark: please see below.

Details on maternal toxic effects:
Cage-side observations and periodic recording of bodyweight suggested no signs of toxicity. There were no discernible effects on nidation.

Dose descriptor:

NOEC

Effect level:

170 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: no effects observed

Abnormalities:

no effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects. Remark: positive control: Aspirin 250.0 mg/kg

Details on embryotoxic / teratogenic effects:
The number of abnormalities seen in either soft or skeletal tissues of the test group did not differ from the number occurring spontaneously in the sham treated control group.

Dose descriptor:

NOEC

Effect level:

170 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No effects observed

Abnormalities:

no effects observed

Developmental effects observed:

not specified

Table 1 - Reproduction data

Dose (mg/kg)	Sham	Positive control*	1.7	8.0	37.0	170.0
Pregnancy
Total no	22	19	22	21	23	20
Died or aborted	1	0	0	0	0	0
To term	21	19	22	21	23	20
Total corpora lutea	281	253	264	246	286	250
Average corpora lutea	11.7	10.5	12.0	10.7	11.9	11.9
Total live litters	21	18	22	21	23	20
Average implant site no	11.4	11.6	11.5	11.5	11.9	12.1
Resorptions
Percent partial resorptions	9.52	26.3	-	9.52	-	25.0
Percent complete resorptions	-	5.26	-	-	-	-
Average live foetus	11.2	9.95	11.5	11.4	11.8	11.8
Sex ratio (m/f)	0.97	0.85	1.17	1.01	0.93	0.73
Dead foetuses	1	6	-	-	1	-
Percent partial dead	4.76	10.5	-	-	4.35	-
percent all dead	-	-	-	-	-	-
Average fetus weight (g)	3.78	2.82	3.95	3.91	3.81	3.71

*Aspirin 250.0 mg/kg

Table 2 - Summary of skeletal findings

Dose (mg/kg)	Sham	Positive control*	1.7	8.0	37.0	170.0
Sternebrae
Incomplete oss	65/19	99/18	35/14	70/19	26/11	35/12
Bipartite	-	7/7	-	1/1	2/2	-
Extra	-	-	-	1/1	-	-
missing	22/11	92/16	16/6	11/7	9/4	6/3
Ribs
Wavy	12/7	46/14	17/6	11/7	20/7	12/6
Less than 12	-	-	1/1	-	-	-
More than 13	-	68/17	-	12/7	-	4/1
Vertebrae
Incomplete oss	18/9	69/17	17/10	22/11	15/10	21/9
Skull
Incomplete closure	34/13	92/17	35/12	34/12	25/13	38/11
Missing	-	1/1	-	-	-	-
Extremities
Incomplete oss	-	15/7	-	-	-	-
Missing	-	-	-	-	-	1/1
Miscellaneous
Hyoid; missing	37/14	70/18	19/12	27/13	29/17	28/10
Hyoid; reduced	18/9	18/11	23/10	25/13	26/8	29/12

(number of foetuses effected/number of litters)

No soft tissue abnormalities were observed except in the sham control and positive control groups

Conclusions:

Under the conditions of the study, the test material administered to pregnant rats for 10 consecutive days up to a dose of 170 mg/kg bw showed no maternal or developmental toxicity. The NOAEL for both maternal and fetoxicity is >170 mg/kg bw. The number of abnormalities seen in either soft or skeletal tissues of the test group did not differ from the number occurring spontaneously in the sham treated control group.

This study is considered to be of adequate reliability and relevance to be submitted as the key study for this endpoint.

Reference 4

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Comparable to OECD guideline 414 with acceptable restrictions. 1. This study is performed on hamsters not on the rat or rabbit as recommended. 2. There is no data on the assessment of gravid uteri.

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See read-across justification report under Section 13 ‘Assessment Reports’.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
In accordance with REACH Annex XI, Section 1.5, of Regulation (EC) No. 1907/2006 (REACH) the standard testing regime may be adapted in cases where a grouping or read-across approach has been applied.

The similarities may be based on:
(1) a common functional group
(2) the common precursors and/or the likelihood of common breakdown products via physical or biological processes, which result in structurally similar chemicals; or
(3) a constant pattern in the changing of the potency of the properties across the category

1. Both substances are inorganic salts of a monovalent cation from Group 1A of the periodic table, and triphosphoric acid. Thus, they share the Na+ or K+ cation and P3O105- anion.
2. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity.
3. In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across. Therefore it is not considered to be scientifically justified to perform any further in vivo studies.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See read-across justification report under Section 13 ‘Assessment Reports’.

3. ANALOGUE APPROACH JUSTIFICATION
See read-across justification report under Section 13 ‘Assessment Reports’.

4. DATA MATRIX
See read-across justification report under Section 13 ‘Assessment Reports’.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

1. This study is performed on hamsters not on the rat or rabbit as recommended. 2. There is no data on the assessment of gravid uteri.

GLP compliance:

not specified

Limit test:

no

Species:

hamster

Strain:

other: Golden

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Housing: mesh bottom cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
Temperature and humidity controlled environment.

Route of administration:

oral: gavage

Vehicle:

water

Analytical verification of doses or concentrations:

no

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1/1
- Proof of pregnancy: sperm in vaginal smear referred to as day 0 of gestation.

Duration of treatment / exposure:

Days 6 through to 10 of gestation.

Frequency of treatment:

Daily

Duration of test:

Treatment began on day 6 and ended on day 10, at day 14 all animals were subjected to caesarean section.

No. of animals per sex per dose:

21 - sham treated control;
20 - positive control;
21- 1.41 mg/kg;
20- 6.5 mg/kg;
20 - 30.0 mg/kg;
21 -141.0 mg/kg

Control animals:

yes, sham-exposed

other: positive control - Aspirin 250.0 mg/kg

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes, for appearance and behaviour
- Time schedule: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 8, 11 and 14

POST-MORTEM EXAMINATIONS: No data
- Sacrifice on gestation day 14

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
Food consumption was monitored to rule out abnormalities of anorexic effects.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No data.
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of resorptions: Yes

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: one third per litter
- Skeletal examinations: Yes: two thirds per litter
- Head examinations: Yes: two third per litter

Details on maternal toxic effects:

Maternal toxic effects:no effects. Remark: please see below.

Details on maternal toxic effects:
Cage-side observations and periodic recording of bodyweight suggested no signs of toxicity. There were no discernible effects on nidation.

Dose descriptor:

NOEC

Effect level:

141 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: no effects observed

Abnormalities:

no effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
The number of abnormalities seen in either soft or skeletal tissues of the test group did not differ from the number occurring spontaneously in the sham treated control group.

Dose descriptor:

NOEC

Effect level:

141 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed

Abnormalities:

no effects observed

Developmental effects observed:

no

Table 1 - Reproduction data

Dose (mg/kg)	Sham	Positive control*	1.41	6.5	30.0	141.0
Pregnancy
Total no	21	20	21	20	20	21
Died or aborted	2	2	3	4	1	2
To term	19	18	18	16	19	19
Total corpora lutea	299	277	289	276	287	295
Average corpora lutea	13.6	11.5	12.0	11.0	11.0	12.3
Total live litters	18	18	18	16	19	18
Average implant site no	13.6	12.3	12.9	12.5	12.3	14.0
Resorptions
Percent partial resorptions	36.8	22.2	50.0	31.3	5.26	26.3
Percent complete resorptions	-	-	-	-	-	5.26
Average live foetus	12.3	11.8	12.3	12.1	12.0	13.0
Sex ratio (m/f)	0.97	0.97	0.91	0.82	0.85	0.82
Dead foetuses	16	1	1	-	3	1
Percent partial dead	15.8	5.56	5.56	-	15.8	5.26
percent all dead	-	-	-	-	-	-
Average foetus weight (g)	1.76	1.75	1.87	1.81	1.77	1.82

*Aspirin 250.0 mg/kg

Table 2 - Summary of skeletal findings

Dose (mg/kg)	Sham	Positive control*	1.41	6.5	30.0	141.0
Sternebrae
Incomplete oss	64/18	50/15	41/14	31/13	65/18	68/17
Bipartite	37/16	16/12	27/11	18/13	18/12	24/12
Fused	-	1/1	1/1	-	1/1	-
Extra	2/2	3/1	7/2	2/1	2/2	3/3
missing	25/10	18/6	31/8	10/6	32/12	24/11
Ribs
Fused/split	-	-	1/1	-	-	-
More than 13	35/13	24/10	20/10	9/5	34/14	29/12
Vertebrae
Incomplete oss	12/18	19/8	10/5	4/2	12/6	17/9
Skull
Incomplete closure	-	-	1/1	-	3/1	-
Extremities
Incomplete oss	46/13	42/12	38/9	23/9	36/12	42/13
Missing	4/3	-	4/3	2/1	-	-
Extra	-	-	2/1	1/1	-	-
Miscellaneous
Hyoid; missing	2/1	4/3	3/3	-	1/1	-
Hyoid; reduced	3/2	4/4	2/2	2/2	7/5	4/2
Ischium; missing	-	1/1	-	-	-	-

(number of foetuses effected/number of litters)

Two foetuses from the 1.41 mg/kg dose group and one from the 30 mg/kg dose group showed soft tissue abnormalities (not at the highest doses).

Conclusions:

Under the conditions of the study, the test material administered to pregnant hamsters for 5 consecutive days up to a dose of 141 mg/kg bw showed no maternal or developmental toxicity. The NOAEL for both maternal and fetoxicity is >141 mg/kg bw.

This study is considered to be of adequate reliability and relevance to be submitted as the key study for this endpoint.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

170 mg/kg bw/day

Additional information

Read across argument: Both substances are ionic inorganic compounds containing a triphosphate anion and a group 1 alkali metal cation. Both the Na+ and the K+ cation have a similar biological function and therefore triphosphate salts of these types are not considered to differ in their systemic toxicity profile; differences arise in their local effects profile due to the increasing or decreasing acidity/alkalinity and buffering capacities of the substances. This has been shown not to have an effect on systemic toxicity. In addition, both salts have been shown to be of similar low toxicity in acute oral studies and therefore comparisons can be drawn to allow read-across. Therefore it is not considered to be scientifically justified to perform any further in vivo studies. Assessment of the key study: In the prenatal developmental toxicity studies, pregnant females received pentasodium triphosphate (anhydrous) during the gestation period by oral intubation. Control groups received the vehicle only (water). At the end of gestation period, all dams were subjected to caesarean section and the number of implantation sites, resorption sites, as well as live and dead foetuses were recorded. The body weights and sex of the live pups were taken. The urogenital tract level of dams was examined for abdominal abnormalities. All foetuses were examined for the presence of external congenital abnormalities. One-third of the foetuses were examined for visceral abnormalities and the remaining two-third were examined for skeletal abnormalities. No maternal toxicity or teratogenic effects were observed at up to the maximum dose levels tested in each species. The NOEL for maternal and foetal toxicity corresponded to the maximum dose tested.

Table 1- Summary of teratogenicity studies with sodium tripolyphosphate

Organism tested	animal / group	Dose (mg/kg bw)	Treatment period (gestation day)	End of gestation	Result (NOEL)
Mouse	24	2.4, 11, 52, 238	6-16	Day 17	238 mg/kg
Rat	24	1.7, 8, 37, 170	6-15	Day 20	170 mg/kg
Hamster	22-25	1.41, 6.5, 30, 141	6-10	Day 14	141 mg/kg
Rabbit	12 -15	2.5, 11.6, 54, 250	6-18	Day 29	250 mg/kg

 

The study conducted in rats is comparable to the modern day guideline OECD 414 - the only deficiency being that gravid uteri were not weighed (it is worth noting that uteri displayed no gross abnormalities when examined at necropsy).

Taken together all 4 studies provide reliable evidence that the test material is not a developmental toxicant.

Justification for classification or non-classification

The NOAEL recorded in the developmental and reproductive toxicity endpoints are for the highest doses tested and are above the limits for classification according to Regulation (EC) 1272/2008 (EU CLP), it is therefore considered that pentapotassium triphosphate will not be classified.