Hydroxylapatite (Ca5(OH)(PO4)3)

Toxicity to reproduction: other studies

Administrative data

Endpoint:

toxicity to reproduction: other studies

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

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2013

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Needle-shaped (nHA-ND) and rod-shaped (nHA-RD) hydroxyapatite (HA) nanoparticles were disolved in water and tagged by Fourrier Transform Infrared (FTIR) and fluorescent spectra. Then varying doses of hydroxyapatite nanoparticles were applicated to a culture of Catfish (Ictalarus punctatus, siluriformes) cells (B cells and T cells) for 24h. Viability was measured by PI staining and the cellular metabolic activity by MTS assay.
Also Zebrafish (Danio rerio, cypriniformes) were exposed to the nanoparticles. Toxicity was reported by death, deformation and hatching rates.

GLP compliance:

not specified

Type of method:

other: both in vitro and in vivo

Test material

Test material information

Constituent 1

Reference substance name:

Hydroxylapatite (Ca5(OH)(PO4)3)

EC Number:

215-145-7

EC Name:

Hydroxylapatite (Ca5(OH)(PO4)3)

Cas Number:

1306-06-5

Molecular formula:

Ca5HO13P3

IUPAC Name:

pentacalcium hydroxide triphosphate

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

nanoparticles of hydroxyapatite, needle- (NHA-ND) and rod-shaped (nHA-RD), synthesized and controlled by Transmission Electron Microscopy.
fluorescein isothiocyanate (FITC) was tagged to the particles for cellular uptake studies

Test animals

Species:

other: fish: in vitro: Ictalurus punctatus (B- and T-cells), in vivo: Dania rerio (embryos)

Strain:

not specified

Sex:

not specified

Administration / exposure

Route of administration:

other: surrounding water

Vehicle:

unchanged (no vehicle)

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

up to 24 h

Frequency of treatment:

once

Doses / concentrations

Remarks:

in vitro: 10 - 300 µg/ml, in vivo: 3 - 300µg/ml

No. of animals per sex per dose:

not reported

Control animals:

yes

Results and discussion

Observed effects

in vitro:Needle-shaped hydroxyapatite nanoparticles inhibit metabolic activity of catfish B cells and T cells. The time-dependent interaction with the test substance revealed that the cytotoxicity of nHA-ND may be caused by slow exocytosis.
in vivo: Both n-HA-forms delayed zebrafish embryo hatching. Approx. 75% of the embryos had malformed spines when exposed to nHA-ND at 120hpf.
The consistent sub-lethal toxic effects observed from the in vitro and in vivo models showed a general correlation between the two studies.

Applicant's summary and conclusion

Conclusions:

Nanoparticles of the trest substance have sub-lethal toxic effects on fish cells and fish embryos.