Acute and Chronic Effects of Sodium Tungstate on an Aquatic Invertebrate (Daphnia magna), Green Alga (Pseudokirchneriella subcapitata), and Zebrafish (Danio rerio)

Abstract

Although aquatic toxicity data exists for tungstate substances, insufficient data of high quality and relevancy are available for conducting an adequate risk assessment. Therefore, a series of acute and chronic toxicity tests with sodium tungstate (Na(2)WO(4)) were conducted on an aquatic invertebrate (Daphnia magna), green alga (Pseudokirchneriella subcapitata), and zebrafish (Danio rerio). Collectively, the data from these studies suggest that sodium tungstate exhibits a relatively low toxicity to these taxa under these test conditions. All studies were conducted in the same laboratory under good laboratory practice standards using Organisation for Economic Co-operation and Development guidelines with the same stock of test material and the same analytical methods. All results are reported as mg W/L. The following toxicity values were based on mean measured concentrations. For D. magna, the 21 day test no-observable effect concentration (NOEC) was 25.9 mg W/L, and the 48-h median effective concentration (EC(50)) from the acute test was >95.5 mg W/L (the highest concentration tested). The P. subcapitata test yielded an ErC(50) of 31 mg W/L. A 38-day test with zebrafish resulted in an NOEC ≥5.74 mg W/L with no effects at any concentration. The 96-h LC(50) from the acute test with zebrafish was >106 mg W/L. The results of the current acute study for daphnids and fish are consistent with published literature, whereas the algae results are different from previously reported values. Transformation/dissolution (T/D) studies, which were conducted according to United Nations Globally Harmonized System of Classification and Labelling of Chemicals protocol, confirmed that the WO (4) (-2) anion accounted for most of the tungsten in solution. For classification purposes, the algae ecotoxity reference value was then compared with T/D data and would not classify Na(2)WO(4) as an aquatic toxicant under the European Union Classification, Labelling and Packaging scheme.

Tungsten Toxicity, Bioaccumulation, and Compartmentalization into Organisms Representing Two Trophic Levels

“…While work was conducted to assess the human health implications and establish provisional screening levels, − there are few environmental regulations on tungsten for the protection of ecological receptors. Safe environmental levels cannot be established due to a paucity of published effects data. , While studies investigating the ecotoxicity and bioaccumulation of W have recently become available, ,,,,− little is known about W bioaccumulation, compartmentalization, and speciation within organisms through dermal and oral routes. Evidence exists for bioaccumulation of W in plants from soil. ,,,,, This implies potential for trophic transfer into the terrestrial food web.…”

Transformation/dissolution characterization of tungsten and tungsten compounds for aquatic hazard classification

“…To derive UN GHS and EU CLP hazard classification outcomes for the W‐bearing substances examined here, the EC50 72‐h P. subcapitata growth rate of 31 mg W/L as the acute ERV, and the ErC10 value of 3.37 mg W/L for D. magna immobility as the chronic ERV, as determined by Clements et al () were used.…”

“…It was proposed that the considerable difference in toxicity between sodium tungstate and sodium metatungstate may be assigned to the latter's "redox and acidic properties," which cause oxidative stress. Clements et al (2012) examined the toxicity of Na 2 WO 4 to an aquatic invertebrate (D. magna), green alga (Pseudokirchneriella subcapitata), and zebrafish (Danio rerio). They reported results from chronic tests showing no-observable effects concentration (NOEC) values of 25.9, 3.37 (based on the growth inhibition rate [ErC10]), and !5.74 mg W/L for daphnids, algae, and zebrafish, respectively.…”

“…Clements et al () examined the toxicity of Na 2 WO 4 to an aquatic invertebrate ( D. magna ), green alga ( Pseudokirchneriella subcapitata ), and zebrafish ( Danio rerio ). They reported results from chronic tests showing no‐observable effects concentration (NOEC) values of 25.9, 3.37 (based on the growth inhibition rate [ErC10]), and ≥5.74 mg W/L for daphnids, algae, and zebrafish, respectively.…”

Adult and Developing Zebrafish as Suitable Models for Cardiac Electrophysiology and Pathology in Research and Industry

“…The model is useful to study the cardiac toxicity induced by pollutants from embryonic to adult stages, showing cardiac malformations and changes in heart rate and in ejection fraction (Wang et al, 2020). These environmental toxicity assays are often performed with zebrafish embryos in combination with other standard models such as Daphnia magna and algae (Clements et al, 2012), while adult fish are kept for evaluating behavioral toxicity (Chagas et al, 2019).…”