Reaction mass of heptachromium tricarbide and trichromium dicarbide

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics in vitro / ex vivo

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Read-across to Cr(III). Radiolabelled 51Cr(III) used in the study. No data on which Cr(III)-salt was used in the study, but the results obtained are likely to give indications on the behaviour of chromium. The release of chromium from chromium carbide is very similar to the release from chromium metal and chromium(III) oxide and therefore read-across can be carried out. Acceptable study report.

Data source

Reference

Reference Type:

publication

Title:

Chromium speciation studies in human plasma and stability studies of Cr(III) and Cr(VI) species in a candidate water reference material.

Author:

Cornelis R, Borguet F, Dyg S, Griepink B.

Year:

1992

Bibliographic source:

Mikrochimica Acta 109, 145-148.

Materials and methods

Objective of study:

distribution

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Plasma from a healthy volunteer was labelled with 51Cr, and the distribution patterns were studied using a liquid chromatography method.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

51Cr(III)

IUPAC Name:

51Cr(III)

Details on test material:

51Cr(III). No other details presented in the publication.

Radiolabelling:

yes

Remarks:

51Cr(III)

Test animals

Species:

other: in vitro

Administration / exposure

Route of administration:

other: in vitro

Details on exposure:

Plasma from a healthy individual was labelled in vitro with 51Cr.

Duration and frequency of treatment / exposure:

Single.

Doses / concentrations

Remarks:

Doses / Concentrations:
No data.

No. of animals per sex per dose / concentration:

Plasma from one human volunteer.

Details on study design:

Plasma from a healthy individual was labelled in vitro with 51Cr.
Much attention was paid to the creation of analysis conditions, which do not disturb the specific Cr-protein associations and gurantee a 100% recovery of the trace elements and of the biomolecules, without degradation.
The separation procedures chosen for the test were:
1) A preliminary cation exchange of the plasma at pH 8 -> collection of the unbound proteins and removal of disturbing proteins (pI>8)
2) Anion exchange of the unbound proteins.
The separations were performed on fast protein liquid chromatography (FPLC) system to avoid denaturation of proteins. The absorbance at 280 nm and the 51Cr elution pattern were detected.
Transferrin and albumin were identified with the aid of electrophoresis and quantified with nephelometry.

Statistics:

No data.

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on distribution in tissues:

The results showed that 85% of the 51Cr was associated with transferrin and 8% with albumin. The rest appears to be spread over other proteins.

Applicant's summary and conclusion

Conclusions:

In vitro studies showed that in the plasma, chromium(III) is mainly bound to transferrin (85%) and albumin (8%).

Executive summary:

Plasma from a healthy individual was labelled in vitro with 51Cr and the association with proteins was determined using fast protein liquid chromatography. 85% of 51Cr was bound to transferrin and 8% to albumin. The remaining part was spread over other proteins.