Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

additional toxicological information
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
supporting study
Study period:
from 1989-09-06 till 1989-10-16
3 (not reliable)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
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 Type:
study report
Report date:

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
according to guideline
other: U.S. EPA FIFRA Guideline 84-4
not specified
GLP compliance:

Test material

Constituent 1
Chemical structure
Reference substance name:
Ammonium thiosulphate
EC Number:
EC Name:
Ammonium thiosulphate
Cas Number:
Molecular formula:
diammonium 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

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