Calcium thiosulphate

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

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

Adequacy of study:

supporting study

Study period:

from 1989-09-06 till 1989-10-16

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP study with deviations: - no metabolic activation was used - concentration of the Ammonium thiosulfate solution is not given The DNA repair assay does not detect chemical induced DNA mutation, therefore not suitable to fulfil the data requirement under REACH for this endpoint. However, may be used as supportive information.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Type of study / information:

The objective of this study was to detect DNA damage caused by the test material, or an active metabolite, by measuring UDS in rat primary hepatocytes in vitro.

Test guideline

Qualifier:

according to guideline

Guideline:

other: U.S. EPA FIFRA Guideline 84-4

Deviations:

not specified

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium thiosulphate

EC Number:

231-982-0

EC Name:

Ammonium thiosulphate

Cas Number:

7783-18-8

Molecular formula:

H3N.1/2H2O3S2

Constituent 2

Reference substance name:

ammonium thiosulfate

IUPAC Name:

ammonium thiosulfate

Details on test material:

- Name of test material (as cited in study report): Ammonium thiosulfate solution (Thio-sul)
- Physical state: clear, colourless liquid
No further details are reported.

Results and discussion

Any other information on results incl. tables

In the in vitro rat primary hepatocyte unscheduled DNA synthese (UDS) assay, the test item, ammonium thiosulfate solution, did not induce significant increses in UDS. In the assay described in this report, freshly prepared rat hepatocytes were exposed to ammonium thiosulfate solution at concentrations ranging from 5000 µg/mL to 0.5 µg/mL in the presence of 10 µCi/mL ³HTdr (40 -60 Ci/mmole). The test item was soluble in media at all concentrations tested. Treatments from 5000 µg/mL to 500 µg/mL were not analysed for nuclear labeling due to high toxicity. Treatments fronm 250 µg/mL to 5 µg/mL covered a good range of toxicity (65.8% to 97.1% survival) and were selected for analysis of nuclear labeling. None of the criteria used to indicate UDS were approached by any of the analysed treatments and no dose-related response was observed.

Applicant's summary and conclusion

Conclusions:

Ammonium thiosulfate solution was evaluated as inactive in the in vitro rat primary hepatocyte UDS assay.