Pentacalcium hydroxide tris(orthophosphate)

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02/02/1982 to 29-05-1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Study not conducted to current guideline, however study is scientifically sound and acceptable for assessment.The results are sufficient in order to derive a reliable conclusion on classification and labelling in accordance with Regulation (EC) No.1272/2008 (EU CLP) and is therefore suitable for use as a key study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: EPA US Guidelines: Hazard Evaluation: Human and Domestic Animals, Fed. Reg. 43:163, 37336-37402 (1978)

Deviations:

no

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

1981

Deviations:

no

GLP compliance:

no

Remarks:

study was conducted in compliance with RTL quality assurance practices, RTL Standard Operating Procedures, and Good Laboratory Practices.

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Pentacalcium hydroxide tris(orthophosphate)

EC Number:

235-330-6

EC Name:

Pentacalcium hydroxide tris(orthophosphate)

Cas Number:

12167-74-7

Molecular formula:

Ca5HO13P3

IUPAC Name:

Calcium hydroxycalcium(1+) phosphate (4:1:3)

Test material form:

solid: particulate/powder

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Portage, Michigan
- Age at study initiation: no data
- Weight at study initiation: The males ranged between 173-219 grams and the females were between 146-173 grams.
- Fasting period before study: Yes; no food 16-18 hours prior to treatment.
- Housing: five per cage in suspended mesh-bottom plastic cages (19" x 10.5" x 8")
- Diet: Purina Rat Chow provided ad libitum
- Water: ad libitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature: 66-72°F (18.9 - 22.2°C)
- no other data on conditions.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 20 mL/kg bw

DOSAGE PREPARATION: The test material was suspended in corn oil after it was passed through a #300 mesh screen.

Doses:

5000 mg/kg bw
Control rats received an equivalent dose of corn-oil only.

No. of animals per sex per dose:

10

Control animals:

yes

Details on study design:

- Duration of observation period following administration: The animals were observed for at least 14 days post treatment for mortality and signs of toxicity.
- Necropsy of survivors performed: Necropsies were performed on any animals that died and on all survivors.
- Observations for clinical signs and mortality will be recorded frequently the first day, and early morning and late afternoon thereafter. These animals will be observed once a day during weekends and holidays. All clinical signs will be recorded as to their onset, duration, and severity. The rats will be weighed on days 0 (prior to treatment), 7, 14, or at death.

Statistics:

no applicable

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

None of the animals died during the treatment or post exposure periods.

Clinical signs:

other: Normal behaviour was reported throughout the study for all animals. The only adverse clinical sign observed in male rats was piloerection (until day 2). In female rats adverse clinical signs included depression, piloerection, and diarrhea. All female rats

Gross pathology:

Autopsy revealed no abnormalities.

Any other information on results incl. tables

Table 1. Changes in body weight recorded for the female control group

Animal No.*	Volume dosed	Time dosed	Daily bodyweight (grams) on day:
			0	7	14
1	4.2	11:00	214	310	358
2	3.9		196	271	310
3	3.7		187	270	321
4	4.0		198	279	321
5	4.1		203	291	342
6	3.8		190	273	324
7	3.7		183	270	333
8	3.6		179	251	311
9	3.5		173	251	302
10	3.6		179	266	319

*Animals 1-5 were in cage A and animals 6-10 were in cage B.

Table 2. Changes in body weight recorded for the male group receiving the test material.

Animal No.*	Volume dosed	Time dosed	Daily bodyweight (grams) on day:
			0	7	14
1	2.0	11:37	195	269	328
2	2.0		196	269	298
3	1.9		188	275	321
4	2.0		204	293	351
5	2.0		200	277	320
6	2.2		219	307	351
7	2.1		209	292	337
8	2.0		202	290	313
9	2.0		199	271	334
10	2.0		197	294	342

*Animals 1-5 were in cage A and animals 6-10 were in cage B.

Table 3. Changes in bodyweight recorded for the female control group

Animal No.*	Volume dosed	Time dosed	Daily bodyweight (grams) on day:
			0	7	14
1	2.9	10:55	146	213	196
2	3.3		166	212	213
3	3.4		171	211	220
4	3.2		163	197	226
5	3.2		159	188	213
6	3.2		161	202	232
7	3.4		168	187	236
8	3.3		165	201	229
9	3.1		156	210	229
10	3.2		158	217	220

*Animals 1-5 were in cage A and animals 6-10 were in cage B.

Table 4. Changes in body weight recorded for the female group receiving the test material.

Animal No.*	Volume dosed	Time dosed	Daily bodyweight (grams) on day:
			0	7	14
1	3.4	11:30	169	209	231
2	3.2		164	200	217
3	3.2		163	200	231
4	3.0		152	190	207
5	3.1		157	197	202
6	3.4		173	210	230
7	3.2		163	196	216
8	3.2		161	202	217
9	3.2		161	198	222
10	3.1		154	189	206

*Animals 1-5 were in cage A and animals 6-10 were in cage B.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test material was found to have an LD50 > 5000 mg/kg bw. Piloerection was reported for one rat after administration, bodyweights were comparable between the control groups and those groups dosed with the test material. At autopsy the animals appeared normal.
In accordance with Regulation (EC) No. 1282/2008 (EU CLP) pentacalcium hydroxide tris(orthophosphate) has not to be classified for acute toxicity via the oral route.