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Cited by 44Planetary Science and ExplorationChemical Analysis and Environmental ImpactPlant Growth and Agriculture Techniques

Perchlorate and Agriculture on Mars

Open access
Oze, Christopher, Beisel, Joshua, Dabsys, Edward, Dall, Jacqueline, North, Gretchen, Scott, Allan, Lopez, Alandra Marie, Holmes, Randall +1 more·2021·Soil Systems
DOI 10.3390/soilsystems5030037
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Abstract

Perchlorate (ClO4−) is globally enriched in Martian regolith at levels commonly toxic to plants. Consequently, perchlorate in Martian regolith presents an obstacle to developing agriculture on Mars. Here, we assess the effect of perchlorate at different concentrations on plant growth and germination, as well as metal release in a simulated Gusev Crater regolith and generic potting soil. The presence of perchlorate was uniformly detrimental to plant growth regardless of growing medium. Plants in potting soil were able to germinate in 1 wt.% perchlorate; however, these plants showed restricted growth and decreased leaf area and biomass. Some plants were able to germinate in regolith simulant without perchlorate; however, they showed reduced growth. In Martian regolith simulant, the presence of perchlorate prevented germination across all plant treatments. Soil column flow-through experiments of perchlorate-containing Martian regolith simulant and potting soil were unable to completely remove perchlorate despite its high solubility. Additionally, perchlorate present in the simulant increased metal/phosphorous release, which may also affect plant growth and biochemistry. Our results support that perchlorate may modify metal availability to such an extent that, even with the successful removal of perchlorate, Martian regolith may continue to be toxic to plant life. Overall, our study demonstrates that the presence of perchlorate in Martian regolith provides a significant challenge in its use as an agricultural substrate and that further steps, such as restricted metal availability and nutrient enrichment, are necessary to make it a viable growing substrate.

AI snapshot

Written from the paper’s full text.

TL;DR

Perchlorate in Martian regolith simulant prevented germination across all plant treatments, while potting soil allowed germination even at 1 wt.% perchlorate but with restricted growth. Flow-through experiments showed perchlorate was not completely removed by water and that it increased metal/phosphorus release from the simulant.

Key findings

  • Perchlorate was uniformly detrimental to plant growth regardless of growing medium. In Martian regolith simulant, perchlorate prevented germination across all plant treatments; only common bean germinated in simulant without added perchlorate, while grain amaranth failed to germinate in simulant regardless of perchlorate concentration.
  • In potting soil, both species germinated in every treatment, but perchlorate reduced growth: amaranth germination rate index differed significantly across perchlorate concentrations (p = 0.011, 2-way ANOVA with Bonferroni), and dry shoot biomass and leaf area differed significantly between groups (p < 0.001 for both).
  • Bean and bean plus Rhizobium treatments did not differ significantly (p = 0.099, t-test), and no nodules formed on bean roots, indicating no established symbiotic association.
  • Soil column flow-through experiments with 1 wt.% perchlorate could not completely remove perchlorate despite its high solubility; in Martian regolith simulant, perchlorate increased metal/phosphorus release, while organic potting soil showed no change in metal release compared to control. Perchlorate left uncovered and not mixed with soil/regolith completely volatilized in less than 12 h.

Methods

  • The authors synthesized a Gusev Crater Martian regolith simulant from New Zealand basalts and volcanic glass, and used a commercial organic potting soil as a control. Magnesium perchlorate was added at 0, 0.5, and 1 wt.% prior to planting.
  • Two plant species were tested: grain amaranth (Amaranthus cruentus) and common bean (Phaseolus vulgaris), with a third treatment of common bean inoculated with Rhizobium. There were five pots per treatment, totaling 90 pots; plants were grown for 8 weeks starting June 2018, first in a greenhouse and then outside on a lightly shaded roof terrace.
  • Germination was scored as percent and date of emergence, and final measurements included leaf area, fresh aboveground weight, and dry weight. Flow-through soil columns were run with ultrapure water at ~1.5 mL h⁻¹, collecting 250 mL per column, with pH, ion chromatography for perchlorate, and ICP-MS for Na, Ca, Mg, P, and K.

Limitations

  • The paper states that synthesizing a targeted Martian simulant at volumes applicable for limited agricultural studies has been a constraint and limitation in previous studies; here, due to limited simulant quantity, regolith simulant was placed in smaller pots (8 × 6 × 6 cm) than potting soil (12 × 10 × 10 cm), though the authors state root growth was not restricted in either pot size.
  • The paper states that the effect of Rhizobium was difficult to discern, possibly due to limited growing time, and no nodules formed, indicating no symbiotic association was established.
  • Evident from the text: the study uses a single Gusev Crater simulant rather than actual Martian regolith, a short 8-week growth period, and does not replicate Martian gravity, radiation, or atmospheric conditions; the authors also state that how to completely remove perchlorate requires further investigation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.3390/soilsystems5030037

Cites

33 of 33 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

4 of 27 cited sources checked · 1 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    Perchlorate concentrations in the range observed on the Martian surface can impair seed germination and plant growth.

    “As this and other studies have shown [19,21], perchlorate concentrations in the range observed on the Martian surface can impair seed germination and plant growth.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [19] Eichler, 2021, Challenging the Agricultural Viability of Martian Regolith Simulants, Icarus source
    • cites [21] Duri, L.G., El-Nakhel, C., Caporale, A.G., Ciriello, M., Graziani, G., Pannico, A., Palladino, M., Ritieni, A., De Pascale, S., and Vingiani, S. (2020). Mars Regolith Simulant Ameliorated by Compost as In Situ Cultivation Substrate Improves Lettuce Growth and Nutritional Aspects. Plants, 9. source

      The Materials and Methods describe lettuce transplanted into mixtures of Mars simulant and compost, while the Discussion suggests that sodium, alkaline pH, and low biological fertility could have stressed plants in pure simulant. Searches for perchlorate, Martian-surface concentrations, and seed germination found no passage connecting perchlorate to impaired germination or growth. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • Findingown data

    Differences in GRI for amaranth in potting soil across all three perchlorate concentrations were significant (p-value = 0.011, 2-way ANOVA with Bonferroni pairwise testing).

    “Differences in GRI for amaranth in potting soil across all three perchlorate concentrations were significant (p-value = 0.011, 2-way ANOVA with Bonferroni pairwise testing).”
    Quote in the paperNot a substantial claim
  • Findingown data

    Seeds of both species germinated in every treatment in organic potting soil, but to varying degrees.

    “Seeds of both species germinated in every treatment in organic potting soil, but to varying degrees.”
    Quote in the paperNot a substantial claim
  • Findingown data

    In Martian regolith simulant, the presence of perchlorate completely inhibited germination across all plant treatments.

    “While germination occurred to some degree across all plants and soil treatments in the potting soil, the presence of perchlorate in the regolith simulant was found to completely inhibit germination.”
    • Also stated in: § Abstract · plain
      “In Martian regolith simulant, the presence of perchlorate prevented germination across all plant treatments.”
    Quote in the paperSubstantial claim
  • Findingown data

    Differences between the bean and bean plus Rhizobium treatments were not significant (p = 0.099, t-test).

    “Differences between the two bean treatments, bean and bean plus Rhizobium (nitrogen-fixing bacteria) were not significant (p = 0.099, t-test).”
    Quote in the paperNot a substantial claim
  • May combine two claims. 16
  • Classified as probably not a substantial claim. 12

  • May combine two claims.

    Premisecitation

    Wamelink et al. showed germination and plant growth using simulant JSC-Mars-1A, including nitrogen fixing plants, but perchlorate was not included.

    “Previously, Wamelink et al. [20] showed germination and plant growth using simulant JSC-Mars-1A, including nitrogen fixing plants; however, perchlorate was not included in the experiments.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [20] Wamelink, G.W.W., Frissel, J.Y., Krijnen, W.H.J., Verwoert, M.R., and Goedhart, P.W. (2014). Can Plants Grow on Mars and the Moon: A Growth Experiment on Mars and Moon Soil Simulants. PLoS ONE, 9. source

      Materials and Methods (Regoliths; page unavailable) identifies the material as JSC-1A Mars regolith simulant, and the Conclusions report germination and growth on the Mars simulant. Species selection includes nitrogen fixers, but the Discussion says the experiment did not test whether nitrogen-fixing bacteria were present or active. The methods do not list perchlorate among the substances analysed or added, but our copy does not explicitly establish that perchlorate was absent from the experiment. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Addition of organic residues increased yields for Lactuca sativa L. var. capitata in MMS.

    “Moreover, addition of organic residues increased yields for Lactuca sativa L. var.capitata in MMS [21].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [21] Duri, L.G., El-Nakhel, C., Caporale, A.G., Ciriello, M., Graziani, G., Pannico, A., Palladino, M., Ritieni, A., De Pascale, S., and Vingiani, S. (2020). Mars Regolith Simulant Ameliorated by Compost as In Situ Cultivation Substrate Improves Lettuce Growth and Nutritional Aspects. Plants, 9. source

  • May combine two claims.

    Premisecitation

    Perchlorate is detrimental to plant growth and a concern in contaminated soils.

    “Perchlorate is detrimental to plant growth and a concern in contaminated soils [7][8][9]”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [7] Parker, 2008, Perchlorate in Groundwater: A Synoptic Survey of “Pristine” Sites in the Coterminous United States, Environ. Sci. Technol. source
    • cites [8] Seyfferth, 2008, Effects of Common Soil Anions and PH on the Uptake and Accumulation of Perchlorate in Lettuce, Plant Soil source
    • cites [9] Sijimol, 2017, Perchlorate in Drinking Water around Rocket Manufacturing and Testing Facilities and Firework Manufacturing Sites in Kerala, India, Energy Ecol. Environ. source

      Section 3.2 (page unavailable) says rainfall could carry perchlorate from soils into water and that perchlorate may reach vegetation through water. This supports concern about environmental contamination, but the paper does not say perchlorate is detrimental to plant growth. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Findingown data

    Only Phaseolus vulgaris (common bean) was able to germinate in Martian regolith simulant, and only without added perchlorate.

    “Of the two plant species, only Phaseolus vulgaris (common bean) was able to germinate in Martian regolith simulant, and only without added perchlorate (Figure 1).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given

    The massive structure created by the addition of water to the Martian regolith simulant will limit water infiltration and root penetration.

    “Additionally, the massive structure created by the addition of water to the Martian regolith simulant will limit water infiltration and root penetration.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Soil column flow-through experiments support that metal release was enhanced by the presence of the Mg perchlorate salt, but primarily when organic matter was not present such as in the Martian simulant.

    “Soil column flow-through experiments support that metal release was enhanced by the presence of the Mg perchlorate salt, but primarily when organic matter was not present such as in the Martian simulant (Figure 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The addition of perchlorate in organic potting soil hindered but did not prohibit plant growth.

    “The addition of perchlorate in Martian regolith prohibited plant growth across all treatments, while the addition of perchlorate in organic potting soil hindered but did not prohibit growth.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Plants in potting soil with 1 wt.% perchlorate showed restricted growth and decreased leaf area and biomass.

    “however, these plants showed restricted growth and decreased leaf area and biomass.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Leaf area functions as a proxy for plant growth.

  • May combine two claims.

    Findingown data

    In potting soil, both amaranth and bean plants were adversely affected with increasing perchlorate, but most were able to germinate.

    “In potting soil (i.e., mainly organic matter with oyster shells), both amaranth and bean plants were adversely affected with increasing perchlorate, but most were able to germinate”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In a recent agricultural study, Martian regolith simulant and high concentrations of perchlorate (2 wt.%) were both determined to be detrimental to plant growth.

    “In a recent agricultural study [19], Martian regolith simulant and high concentrations of perchlorate (2 wt.%) were both determined to be detrimental to plant growth.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [19] Eichler, 2021, Challenging the Agricultural Viability of Martian Regolith Simulants, Icarus source

  • May combine two claims.

    Study design and conductcitation

    The synthesized regolith analogue is representative of the Gusev Crater, reproducing its particle size, chemistry, and mineralogy.

    “Here, we synthesized a regolith analogue representative of the Gusev Crater (i.e., located near the Columbia Hills region on Mars) via crushing, sieving, washing, and blending of New Zealand basalts and volcanic glass to reproduce the site's particle size, chemistry, and mineralogy (see Scott et al., 2017).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Scott et al., 2017 source

  • May combine two claims.

    Premisecitation

    Perchlorate concentrations in Martian regolith vary spatially and with depth, with values as high as 2 wt.%.

    “Concentrations of perchlorate vary spatially and with depth, with values as high as 2 wt.% [6].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [6] Scott, 2017, Development of a Martian Regolith Simulant for In-Situ Resource Utilization Testing, Acta Astronaut. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Perchlorate salts are hypothesized to be present over the entire surface of Mars due to atmospheric circulation and wind transport of sediments.

    “With atmospheric circulation and wind transport of sediments, perchlorate salts are hypothesized to be present over the entire surface of Mars [16][17][18].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [16] Rieder, 1997, The Chemical Composition of Martian Soil and Rocks Returned by the Mobile Alpha Proton X-Ray Spectrometer: Preliminary Results from the X-Ray Mode, Science source
    • cites [17] Carrier, 2015, The Origins of Perchlorate in the Martian Soil, Geophys. Res. Lett. source
    • cites [18] Clark, 2016, Evidence for the Distribution of Perchlorates on Mars, Int. J. Astrobiol. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    The flow rate used in the soil column experiments was based on those observed in similar soils on Earth while accounting for the difference in gravity on Mars.

    “The flow rate was based on those observed in similar soils on Earth while accounting for the difference in gravity on Mars [25].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [25] Seven, 1981, Water Flow in Soil Macropores II. A Combined Flow Model, J. Soil Sci. source

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Rhizobium are nitrogen-fixing bacteria that form symbiotic relationships with legumes and allow them to fix nitrogen into the soil.

    “Rhizobium are nitrogen-fixing bacteria that form symbiotic relationships with legumes and allow them to fix nitrogen into the soil [24].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [24] Bardgett, 2008, The Unseen Majority: Soil Microbes as Drivers of Plant Diversity and Productivity in Terrestrial Ecosystems, Ecol Lett. source

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    Direct phytotoxicity, salt stress, metal release, or some combination of these variables will stress or inhibit seed germination and plant growth.

    “For example, direct phytotoxicity, salt stress, metal release, or some combination of these variables will stress or inhibit seed germination and plant growth.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    Our results suggest that perchlorate volatilization, the introduction of organic material, and phytoremediation are three different approaches that would beneficially mediate the detrimental aspects of perchlorate in Martian regolith.

    “Overall, how to completely remove perchlorate requires further investigation and our results suggest that perchlorate volatilization, the introduction of organic material, and phytoremediation are three different approaches that would beneficially mediate the detrimental aspects of perchlorate in Martian regolith.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Martian regolith simulant is representative of actual Martian regolith for the properties studied.
    • Rests on an assumption: The volatilization of perchlorate observed in laboratory conditions would occur similarly in Martian soil/regolith.

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    The development of soil structure will be crucial for providing textural and water-holding properties beneficial for seed germination and seedling growth.

    “More importantly, the development of soil structure will be crucial for providing textural and water-holding properties that will be beneficial for seed germination and seeding growth.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    With perchlorate in Martian regolith, osmotic stress may make plant growth difficult.

    “With the perchlorate in Martian regolith, osmotic stress may make plant growth difficult.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Martian regolith would be expected to behave similarly (massive structure from cementation) or be more reactive with water than the experimental regolith, due to desiccation and irradiation over billions of years and the nature of particle sizes and minerals.

    “With desiccation and irradiation of the Martian regolith over billions of years as well as the nature of the particle sizes and minerals, it would be expected that Martian regolith would behave similarly (i.e., massive structure from cementation) or be more reactive with water to those in our experiments.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Martian regolith simulant is representative of actual Martian regolith for the properties studied.

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Limitations to plant growth are directly related to chemical and/or physical stress which may or may not be related to the presence of perchlorate.

    “Limitations to plant growth are directly related to chemical and/or physical stress which may or may not be related to the presence of perchlorate.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Metal release might be related to a salt effect or oxidative release.

    “These observations begin to clarify that metal release might be related to a salt effect or oxidative release.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationown data

    Our results highlight the need to develop effective methods for perchlorate removal prior to using Martian regolith as a planting substrate.

    “Our results highlight the need to develop effective methods for perchlorate removal prior to using Martian regolith as a planting substrate; however, perchlorate is not the only issue at hand.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationreasoning

    Removing perchlorate through volatilization or leaching is needed, coupled with regolith amendment with organic matter to promote structure and nutrient cycling.

    “Overall, removing perchlorate through volatilization or leaching, for example, is needed, coupled with regolith amendment with organic matter to promote structure and nutrient cycling.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Martian regolith simulant is representative of actual Martian regolith for the properties studied.
24 of 24

  • The paper relies on this without support.

    Dry shoot biomass is an indicator of plant productivity and overall health.

    “Dry shoot biomass is an indicator of plant productivity and overall health.”

  • The paper relies on this without support.

    Leaf area functions as a proxy for plant growth.

    “Leaf area functions as a proxy for plant growth (Figure 2C).”

  • The paper relies on this without support.

    Martian regolith simulant is representative of actual Martian regolith for the properties studied.

    “With desiccation and irradiation of the Martian regolith over billions of years as well as the nature of the particle sizes and minerals, it would be expected that Martian regolith would behave similarly (i.e., massive structure from cementation) or be more reactive with water to those in our experiments.”

  • The paper relies on this without support.

    The volatilization of perchlorate observed in laboratory conditions would occur similarly in Martian soil/regolith.

    “From our observations, methods that promote perchlorate volatilization may present another feasible remediation pathway.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Toxic perchlorate salts occur commonly on the Martian surface in concentrations of 0.5-1%.

    “Due to the phytochemistry of the cold and oxidizing environment, toxic perchlorate salts occur commonly on the Martian surface in concentrations of 0.5-1% (Oze et al., 2021); however, they were not present in any of the 30 simulants.”

    From The Potential for Lunar and Martian Regolith Simulants to Sustain Plant Growth: A Multidisciplinary Overview (2022) · cites this paper as Oze et al., 2021

    The Introduction reports perchlorate wherever landers and rovers have explored and describes it as detrimental to plant growth. It says concentrations vary by location and depth, reaching as high as 2 wt.%; Section 2.1 identifies 0.5 and 1 wt.% as concentrations added in experiments, not as a commonly observed Martian range. The Introduction discusses possible atmospheric chemical origins, but does not attribute perchlorate formation to phytochemistry. (LLM, conf=0.89)

    Experimental — accuracy not yet measured

  • In Martian simulants, perchlorate caused uniform reduction in plant growth and prevented germination compared to no perchlorate, and promoted elevated metal and phosphorus release.

    “For instance, the presence of perchlorate in Martian simulants led to uniform reduction in plant growth and prevention of plant germination compared to no perchlorate treatments, along with promoting elevated metal and phosphorus release from the simulants (Oze et al., 2021).”

    From Simple and effective remediation strategies of Martian perchlorates (2026) · cites this paper as Oze et al., 2021

  • In Oze et al. (2021), complete loss of perchlorate with leaching from Martian simulant was not obtained, and the concentration of remaining perchlorate was not stated.

    “In their study, complete loss of perchlorate with leaching from Martian simulant was not obtained; however, the concentration of remaining perchlorate was not stated (Oze et al., 2021).”

    From Simple and effective remediation strategies of Martian perchlorates (2026) · cites this paper as Oze et al., 2021

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Experiment duration differs between methods and figure caption

    Major

    The methods say the experiments lasted 8 weeks, while Figure 1 describes a 29-day growing period.

  • Conflicting descriptions of the leaf-area response

    Major

    The results describe leaf area in potting soil as decreasing with increasing perchlorate, but later state that leaf area had no concentration-dependent relationship with perchlorate.

2 of 2

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Related

Authors
Oze, C., Beisel, J., Dabsys, E., Dall, J., North, G., Scott, A., Lopez, A. M., Holmes, R., & Fendorf, S.
Affiliations
  • Occidental College (US)
  • University of Canterbury (NZ)
  • Stanford University (US)
Corresponding author
Oze, Christopher
ORCID
Venue
Soil Systems
Publisher
MDPI AG
Published
2021-06-24
Volume
5
Issue
3
Pages
37
ISSN
2571-8789 (ISSN-L)
DOI
10.3390/soilsystems5030037
OpenAlex
W3173308197
Semantic Scholar
d5453eaabc2d2a4d984c0c94acd06eea3cefb764
Cited by
44
References
32
Citations by year
2026: 10 · 2025: 9 · 2024: 9 · 2023: 9 · 2022: 6 · 2021: 1
FWCI
3.36
Type
journal article
Language
en
Open access
Licence
Locations
  • Soil Systems (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Topics
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Planetary Science and Exploration
  • Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Chemical Analysis and Environmental Impact
  • Life Sciences › Agricultural and Biological Sciences › Soil Science › Plant Growth and Agriculture Techniques
Keywords
perchlorate, Martian regolith, plant growth, seed germination, regolith simulants, Gusev Crater, metal release, phosphorus availability, perchlorate removal, potting soil, phytotoxicity

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

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Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-11-03.

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