Trichromium dicarbide

Exposure related observations in humans: other data

Administrative data

Endpoint:

exposure-related observations in humans: other data

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: Acceptable study report which meets basic scientific principles. Read-across from chromium chloride. This salt is more soluble than trichromium dicarbide, but it can be used for indicating general issues of chromium kinetics.

Data source

Reference

Reference Type:

publication

Title:

Intestinal absorption of trace quantities of chromium.

Author:

Donaldson, R. M., Jr. and R. F. Barreras

Year:

1966

Bibliographic source:

J Lab Clin Med.68(3): 484-93.

Materials and methods

Type of study / information:

Absorption and excretion of radiolabelled trivalent chromium studied in human volunteers.

Endpoint addressed:

basic toxicokinetics

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Absorption and excretion of radiolabelled trivalent chromium was studied in human volunteers.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Chromium chloride

IUPAC Name:

Chromium chloride

Details on test material:

Radiolabelled chromium chloride Cr[51]Cl3. No other details presented.

Method

Ethical approval:

not specified

Details on study design:

Volunteer patients (n=6) were orally given a dose of 20 ng of Cr[51]Cl3 containing 0.5 to 1 µc of radioactivity. In two patients, the dose was injected directly into the duodenum through a fine tube. For measuring intestinal absorption, an intestinal perfusion technique was applied.

Exposure assessment:

measured

Details on exposure:

TYPE OF EXPOSURE: Single oral dose, or direct injection into the duodenum through a polyvinylchloride tube.


TYPE OF EXPOSURE MEASUREMENT: / Biomonitoring (urine and faeces)


EXPOSURE LEVELS: 20 ng


EXPOSURE PERIOD: single dose


POSTEXPOSURE PERIOD: 6 days of follow-up. urine was collected for 24 h and faeces for 6 days.

Results and discussion

Results:

The mean recovery of faecal radioactivity was 99.6% after oral administration and 93.7% after duodenal administration. The urinary excretion was 0.5% and 0.6% after oral and duodenal exposure, respectively.

Applicant's summary and conclusion

Conclusions:

The oral bioavailability of trivalent chromium was very low, as tested in human volunteers.

Executive summary:

In the study by Donaldson and Barreras (1966), volunteer patients (n=6) were orally given a dose of 20 ng of Cr[51]Cl3 containing 0.5 to 1 µc of radioactivity. In two patients, the dose was injected directly into the duodenum through a fine tube. For measuring intestinal absorption, an intestinal perfusion technique was applied. The mean recovery of faecal radioactivity was 99.6% after oral administration and 93.7% after duodenal administration. The urinary excretion was 0.5% and 0.6% after oral and duodenal exposure, respectively.