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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Endpoint:
biological effects monitoring
Type of information:
other: published data
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
The Sodium O-isopropyl dithiocarbonate (CAS No. 140-93-2), the subject of this dossier) is expected to exhibit very similar toxicity to sodium O-ethyl dithiocarbonate CAS No 140-90-9, which is also xanthate compound. Comparable metabolism would occur.

Data source

Reference
Reference Type:
review article or handbook
Title:
Priority existing chemical Report No. 5
Author:
Dep. of Health and Ageing, Australian Government
Year:
1995
Bibliographic source:
National Industrial Chemicals Notification and Assessment Scheme

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Determination of carbon disulphide concentrations in blood or urine by Iodine-azide test and Estimation of urinary thio-thiazolidine-4-carboxylic acid (TTCA)
GLP compliance:
no
Type of study / information:
Biological monitoring for determination of carbon disulphide concentrations in blood or urine.

Test material

Constituent 1
Chemical structure
Reference substance name:
Sodium O-ethyl dithiocarbonate
EC Number:
205-440-9
EC Name:
Sodium O-ethyl dithiocarbonate
Cas Number:
140-90-9
Molecular formula:
C3H6OS2.Na
IUPAC Name:
sodium O-ethyl dithiocarbonate
Test material form:
solid: compact
Details on test material:
The Sodium Isopropyl Xanthate (SIPX) (CAS No.140-93-2 ), the subject of this dossier) is expected to exhibit very similar toxicity to Sodium ethyl xanthate (CAS No. 140-90-9)), which is also xanthate compound. Comparable metabolism would occur.

Results and discussion

Any other information on results incl. tables

Biological monitoring

Sodium Isopropyl Xanthate (SIPX) readily decomposes to carbon disulphide, especially in the presence of moisture/water. Therefore, the health effects of carbon disulphide (CS2) need to be considered in the assessment of Sodium Isopropyl Xanthate (SIPX).

It is generally considered that adverse effects from exposure to xanthates (inhumans and animals) are associated with CS2 toxicity. It is not known what contribution to human toxicity is likely from inhalation/dermal absorption of CS2per se, as a xanthate decomposition product, and CS2 as a xanthate metabolite.

Determination of carbon disulphide concentrations in blood or urine is not useful as ameasure of exposure, as only 1% of the absorbed carbon disulphide is excretedunchanged in the urine.Estimation of the concentration of the metabolites of carbondisulphide can be used as a measure of exposure.

 

Iodine-azide test

The iodine-azide test is based on the capacity of a metabolite of carbon disulphide to catalyse the iodine-azide reaction. The time required for decolourisation ofiodine after addition of the iodine-azide reagent to the urine is an indication of theamount of carbon disulphide metabolite in the urine. The time is inversely andexponentially related to the concentration of the metabolite. The time is correctedaccording to the creatinine concentration to avoid collection of 24 hr urine samples.

An exposure coefficient can be calculated from the creatinine concentration.The iodine-azide reaction catalysed by the metabolite probably a thiazolidine is:

 

2NaN3+ I2→ 3N2+ 2NaI

 

This method is sensitive to atmospheric concentrations of 16 ppm and above of carbondisulphide. Exposure is considered to be negligible if decolourisation does not occurwithin 3 hrs. This method is not a precise method of monitoring and only indicatesoverexposure.

 

This method has been modified by Jakubowski9 and is based on measurement of theamount of iodine used for titration of the carbon disulphide metabolites thatcatalyse the iodine-azide reaction. This method can be used to assess exposure tocarbon disulphide levels as low as 3 ppm.

 

Determination of thio compounds

Estimation of urinary thio-thiazolidine-4-carboxylic acid (TTCA) concentration by high performance liquid chromatography may be used to monitor carbon disulphideexposure. TTCA is formed in the body by the reaction between carbon disulphideand glutathione. Excretion of TTCA may reflect the rate of metabolism of carbon disulphide rather than exposure.

 

Applicant's summary and conclusion

Conclusions:
Sodium Isopropyl Xanthate (SIPX) readily decomposes to carbon disulphide, especially in the presence of moisture/water. Therefore, the health effects of carbon disulphide (CS2) need to be considered in the assessment of Sodium Isopropyl Xanthate (SIPX).
It is generally considered that adverse effects from exposure to xanthates (in humans and animals) are associated with CS2 toxicity. It is not known what contribution to human toxicity is likely from inhalation/dermal absorption of CS2 per se, as a xanthate decomposition product, and CS2 as a xanthate metabolite.
Determination of carbon disulphide concentrations in blood or urine is not useful as a measure of exposure, as only 1% of the absorbed carbon disulphide is excreted unchanged in the urine. Estimation of the concentration of the metabolites of carbon disulphide can be used as a measure of exposure.