[No public or meaningful name is available]

Endpoint summary

Description of key information

oral: A study examined whether the bioavailability of the read-across substance calcium carbonate could be improved by reducing the particle size. Because nanoscale supplements are novel formulas in health foods, the acute toxicity, sub-chronic toxicity (see separate IUCLID entry) and bioavailability (see separate IUCLID entry) needs to be determined in both sexes of mice in advance.

Standard acute toxicological evaluations of the ICR mice were performed in the initial assessment of the effects of nanoscale calcium carbonate internalisation. Micro calcium carbonate and nano calcium carbonate were administered in a single dose by gavage using a gastric intubation tube. The animals were then observed for a period of 7 days. No mortality or unusual behaviour were observed in an acute oral toxicity study. The NOAEL for both micro calcium carbonate and nano calcium carbonate were reported to be 1.3 g/kg bw, wich was the highest dose tested.

dermal: The acute dermal median lethal dose (LD50) of the read-acorss substance uncoated nano calcium carbonate in the Wistar strain rat was found to be greater than 2000 mg/kg bodyweight.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

19 November 2007 to 11 December 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Specific details on test material used for the study:

Bulk calcium carbonate

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd, Margate, Kent, UK
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: 205-237 g
- Fasting period before study: overnight prior to dosing
- Housing: suspended polypropylene cages furnished with soft woodflakes and fitted with stainless steel lids.
- Diet: ad libitum (except overnight prior to dosing and 3-4 hours after dosing)
- Water: ad libitum
- Acclimation period: at least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25 °C
- Humidity (%): 30 to 70%
- Air changes (per hr): At least 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours of continuous artificial light in each 24 hour period.

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg

Doses:

2000 mg/kg

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: general observations - at 0.5, 1, 2 and 4 hours after dosing then again at least once daily for 14 days; bodyweights were recorded on days 0, 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs.

Statistics:

No data

Preliminary study:

The female test animal did not die during the study following a single oral dose of 2000 mg/kg bw. There were no clinical signs during the preliminary study.

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Sex:

female

Dose descriptor:

LD0

Effect level:

> 2 000 mg/kg bw

Mortality:

No mortalities occurred.

Clinical signs:

other: No clinical signs of systemic toxicity were observed.

Gross pathology:

No adverse effects were observed.

Interpretation of results:

GHS criteria not met

Conclusions:

The acute oral median lethal dose (LD50) of the test material in the female Sprague-Dawley rat was estimated to be > 2000 mg/kg bw

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Qualifier:

no guideline followed

Principles of method if other than guideline:

The study examined whether the bioavailability of calcium carbonate and calcium citrate could be improved by reducing the particle size. Because nanoscale supplements are novel formulas in health foods, the acute toxicity, sub-chronic toxicity (see separate IUCLID entry) and bioavailability (see separate IUCLID entry) needs to be determined in both sexes of mice in advance.
Standard acute toxicological evaluations of the ICR mice were performed in the initial assessment of the effects of nanoscale calcium carbonate internalisation. Micro calcium carbonate and nano calcium carbonate were administered in a single dose by gavage using a gastric intubation tube. The animals were then observed for a period of 7 days.

GLP compliance:

no

Specific details on test material used for the study:

Uncoated nano calcium carbonate

Species:

mouse

Strain:

ICR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: National Taiwan University Hospital, Taipei, Taiwan
- Age at study initiation: 8-10 weeks
- Fasting period before study: Animals were fasted overnight
- Diet: Pelleted mouse feed available ad libitum
- Water: Reverse osmosis water available ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-25 °C
- Humidity (%): 30-70%
- Photoperiod (hrs dark / hrs light): 12 h/12 h day/night cycle


Sham surgery (n = 6, SHAM) or bilateral ovariectomy (n = 30, OVX) was performed from a dorsal approach at 6 to 8 week old mice. Surgical removal of the ovaries is a well-represented approach to mimic the postmenopausal condition in mice. In the sham operation, ovaries were exteriorised and then replaced.

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The test materials were administered in a single dose by gavage using a gastric intubation tube.

Doses:

Vitamin D3 (261 U/ kg bw) plus micro calcium carbonate: 1.3 g/kg bw
Vitamin D3 (261 U/ kg bw) plus nano calcium carbonate: 1.3 g/kg bw

No. of animals per sex per dose:

8 animals/sex/dose

Control animals:

yes

Details on study design:

On day seven, all the animals were weighed and any signs of toxicity were noted.

Sex:

male/female

Dose descriptor:

other: NOAEL

Effect level:

1 300 mg/kg bw

Mortality:

No mortality was observed.

Clinical signs:

other: Throughout the study, no unusual behaviour or differences between groups were observed (i.e. no laboured breathing, difficulty moving, hunching or unusual interactions with cage mates were observed).

Table 1: Body weight and mortality during the 7-day acute toxicity test

Dose	Sex (n)	Initial body weight (g)	Final body weight (g)	Mortality dead/treated
Control	Male (8) Female (8)	33.2 ± 3.3 32.5 ± 3.7	35.3 ± 3.9 34.2 ± 3.8	0/8 0/8
Micro calcium carbonate (1.3 g/kg bw)	Male (8) Female (8)	33.4 ± 3.2 32.7 ± 3.4	34.9 ± 3.2 34.3 ± 3.6	0/8 0/8
Nano calcium carbonate (1.3 g/kg bw)	Male (8) Female (8)	32.5 ± 3.6 33.1 ± 2.9	33.7 ± 4.1 34.9 ±3.8	0/8 0/8

Data are mean ± SE values

 

Interpretation of results:

GHS criteria not met

Conclusions:

No mortality or unusual behaviour were observed during the course of the study. The NOAEL for both micro calcium carbonate and nano calcium carbonate were reported to be 1.3 g/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

06 January 2010 - 20 January 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Specific details on test material used for the study:

Uncoated nano calcium carbonate

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Limited, Bicester, Oxon, UK
- Age at study initiation: 8-12 weeks
- Weight at study initiation: at least 200 g
- Fasting period before study: No data
- Housing: The animals were housed in suspended solid floor polypropylene cages furnished with woodflakes. The animals were housed individually during the 24-hour exposure period and in groups of five, by sex, for the remainder of the study.
- Diet (e.g. ad libitum): Food (2014 Teklad Global Rodent diet) was available ad libitum.
- Water (e.g. ad libitum): Mains drinking water was available ad libitum.
- Acclimation period: At least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25 °C
- Humidity (%): 30-70%
- Air changes (per hr): at least fifteen changes per hour
- Photoperiod (hrs dark / hrs light): twelve hours continuous light (06:00 to 18:00) and twelve hours darkness

Type of coverage:

semiocclusive

Vehicle:

arachis oil

Details on dermal exposure:

TEST SITE
- Area of exposure: back and flanks of each animal
- % coverage: approximately 10% of the total body surface area
- Type of wrap if used: A piece of surgical gauze was placed over the treatment area and semi-occluded with a piece of self-adhesive bandage.


REMOVAL OF TEST SUBSTANCE
- Washing (if done): After the 24-hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with arachis oil BP to remove any residual test material.
- Time after start of exposure: 24 h


TEST MATERIAL
The appropriate amount of test material, moistened with arachis oil BP, was applied as evenly as possible to an area of shorn skin using a graduated syringe.

Duration of exposure:

24 h

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 animals/ sex/ dose

Control animals:

not specified

Details on study design:

The animals were observed for deaths or overt signs of toxicity 0.5, 1, 2 and 4 hours after dosing and subsequently once daily for fourteen days.

After removal of the dressings and subsequently once daily for fourteen days, the test sites were examined for evidence of primary irritation and scored according to the scale from Draize (1977).

Individual bodyweights were recorded prior to application of the test material on Day 0 and on Days 7 and 14.

At the end of the study the animals were killed by cervical dislocation. All animals were subjected to gross necropsy. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

There were no deaths.

Clinical signs:

other: There were no signs of systemic toxicity or dermal irritation.

Gross pathology:

No abnormalities were noted at necropsy.

Table 1: Individual clinical observations and mortality data

Dose level (mg/kg)	Animal no. & sex	Effects noted after initiation of exposure (hours)				Effects noted after initiation of exposure (days)
		0.5	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	Males (1-1, 1-2, 1-3 & 1-4)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	Females (2-1, 2-2, 2-3 & 2-4)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0 = no signs of systemic toxicity

 

 

Table 2: Individual dermal reactions – Males

Dose level (mg/kg)	Animal no. & sex	Observation	Effects noted after initiation of exposure (days)
			1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	Males (1-1, 1-2, 1-3 & 1-4)	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Oedema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0 = No reactions

 

 

Table 3: Individual dermal reactions – Females

Dose level (mg/kg)	Animal no. & sex	Observation	Effects noted after initiation of exposure (days)
			1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	Females (2-1, 2-2, 2-3 & 2-4)	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Oedema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0 = No reactions

 

 

Table 4: Individual bodyweights and weekly bodyweight changes

Dose level (mg/kg)	Animal no. & sex	Bodyweight (g) at Day			Bodyweight change (g) during week
		0	7	14	1	2
2000	1-0 Male	232	256	278	24	22
	1-1 Male	235	255	270	20	15
	1-2 Male	242	268	288	26	20
	1-3 Male	224	246	270	22	24
	1-4 Male	234	261	279	27	18
	2-0 Female	220	228	239	8	11
	2-1 Female	203	204	216	1	12
	2-2 Female	211	216	218	5	2
	2-3 Female	217	220	230	3	10
	2-4 Female	212	213	220	1	7

 

 

Table 5: Individual necropsy findings

Dose level (mg/kg)	Animal no. & sex	Macroscopic observations
2000	Males (1-1, 1-2, 1-3 & 1-4)	No abnormalities detected
	Females (2-1, 2-2, 2-3 & 2-4)	No abnormalities detected

 

 

Interpretation of results:

GHS criteria not met

Conclusions:

The acute dermal median lethal dose (LD50) of the test material in the Wistar strain rat was found to be greater than 2000 mg/kg bodyweight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available data for acute toxicity are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on this data, the substance is not considered to be classified for acute toxicity under Regulation (EC) No 1272/2008, as amended for the eighteenth time in Regulation (EU) 2022/692.