Acute toxicity of thioarsenates to <i>Vibrio fischeri</i>
Bibliographic record
Abstract
Thioarsenic species often are the predominant arsenic species in sulfidic environments, yet little is known about their toxicity. We report to our knowledge the first determination of acute toxicity of mono-, di-, and trithioarsenate to the bioluminescent bacterium Vibrio fischeri, which increases with an increasing number of thio(SH)-groups. Whereas mono- and dithioarsenate are much less toxic (effective analyte concentration causing a 50% decrease in luminescence [EC50], 676 and 158 mg/L, respectively), the toxicity of trithioarsenate (EC50, 14.4 mg/L) is comparable to the toxicities of arsenate and arsenite (EC50, 9.1 and 26.1 mg/L, respectively). The low toxicity of monothioarsenate is remarkable, because it has chemical properties very similar to those of arsenate. In contrast to the toxicities of arsenite and arsenate, the toxicity of thioarsenates increases with exposure time, suggesting a lack of detoxification mechanisms or a conversion of thioarsenic species into arsenic oxyanions after uptake. We determined the acute toxicity of synthetic arsenite solutions with varying sulfide concentration to V. fischeri. Arsenic speciation in these solutions was measured by ion chromatography-inductively coupled plasma-mass spectrometry, and the observed toxicity was related to the different arsenic species present. High inhibition of luminescence was observed at low and high ratios of sulfur to arsenic, in which arsenite or a mixture of di-, tri-, and tetrathioarsenate dominated arsenic speciation. Acute toxicity decreased at sulfur to arsenic ratios of from 1 to 10, with a minimum luminescence inhibition of 30% at a ratio of 3.5, at which concentrations of 55 mg/L of arsenite and 30 mg/L of trithioarsenate were determined. The toxicity observed under these conditions is much lower than that anticipated from the individual dose-response curves that predict each species alone already should cause 70 to 80% inhibition. The low toxicity suggests an antagonistic toxicological interaction between arsenite and trithioarsenate.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".