Registration Dossier

Administrative data

Endpoint:
basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
publication
Title:
TR-599: Technical Report Pathology Tables and Curves - TR-599: Sodium Tungstate Dihydrate - 3-Month with Perinatal Study Tables - Rats
Author:
US NTP
Year:
2019
Bibliographic source:
https://tools.niehs.nih.gov/cebs3/views/?action=main.dataReview&bin_id=14351

Materials and methods

Objective of study:
absorption
excretion
Principles of method if other than guideline:
During the 90-day drinking water study with Sodium Tungstate Dihydrate, tungsten concentrations were determined in blood and in urine
GLP compliance:
not specified

Test material

Constituent 1
Reference substance name:
disodium dioxotungstenbis(olate) dihydrate
EC Number:
600-275-2
Cas Number:
10213-10-2
Molecular formula:
Na2WO4* 2 H2O
IUPAC Name:
disodium dioxotungstenbis(olate) dihydrate
Test material form:
solid - liquid: aqueous solution
Details on test material:
Sodium tungstate dihydrate (STD, Na2WO4·2H2O, CAS #10213-10-2, Lot #12330JO) was obtained through an NTP analytical chemistry contract at Battelle (Columbus, OH). Stability data provided by Battelle indicated that formulations of STD in tap water were stable for at least 42 days at both 5°C and at room temperature.
Radiolabelling:
no

Test animals

Species:
rat
Sex:
male/female

Administration / exposure

Route of administration:
oral: drinking water
Vehicle:
unchanged (no vehicle)
Doses / concentrationsopen allclose all
Dose / conc.:
125 mg/L drinking water
Dose / conc.:
250 mg/L drinking water
Dose / conc.:
500 mg/L drinking water
Dose / conc.:
1 000 mg/L drinking water
Dose / conc.:
2 000 mg/L drinking water
No. of animals per sex per dose / concentration:
5
Control animals:
yes, concurrent no treatment

Results and discussion

Main ADME resultsopen allclose all
Type:
absorption
Results:
on study day 78, a dose-dependent increase in tungsten concentration in blood was observed over all dose groups.
Type:
excretion
Results:
A dose-dependent increase in tungsten urine concentration was observed for all dose groups on study day 78.

Metabolite characterisation studies

Metabolites identified:
no
Remarks:
The test substance is inorganic.

Applicant's summary and conclusion

Conclusions:
If tungsten is applied in a soluble form (Sodium Tungstate Dihydrate), tungsten ions are found in blood and urine.