{ "id": "epfq9tam8q", "slug": "brine-shrimp-lethality-test", "title": "Brine shrimp lethality test", "updated": "2026-10-15", "topic_path": [ { "id": "life", "label": "Life and health", "api_url": "https://www.edgepedia.org/api/v1/topics/life" }, { "id": "life.health", "label": "Human health and medicine", "api_url": "https://www.edgepedia.org/api/v1/topics/life.health" } ], "geo": [ { "id": "geo.nongeo.t1946.life.health", "label": "Non-geographic · 1946 to 2000: Human health and medicine", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health", "path": [ { "id": "geo.nongeo", "label": "Non-geographic", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo" }, { "id": "geo.nongeo.t1946", "label": "Non-geographic · 1946 to 2000", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946" }, { "id": "geo.nongeo.t1946.life", "label": "Life and health", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life" }, { "id": "geo.nongeo.t1946.life.health", "label": "Human health and medicine", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health" } ] } ], "excerpt": "The brine shrimp lethality test is a bench-top bioassay that measures the concentration of an extract or compound needed to kill half of laboratory-hatched brine shrimp larvae.", "snippet": "The brine shrimp lethality test is a bench-top bioassay that measures the concentration of an extract or compound needed to kill half of laboratory-hatched brine shrimp larvae.", "node": "life.health", "markdown": "# Brine shrimp lethality test\n\nThe brine shrimp lethality test is a bench-top bioassay that measures the ability of crude extracts or purified compounds to kill laboratory-hatched brine shrimp (Artemia) nauplii, reported as a lethal concentration. It serves as a first-pass toxicity and cytotoxicity screen in natural products research, where large numbers of extracts must be triaged cheaply before more expensive cell-line or animal testing.\n\n| Key fact | Detail |\n|---|---|\n| What it measures | Concentration killing 50% of nauplii (\\( LC_{50} \\)), typically after 24–48 h exposure[1](https://pubmed.ncbi.nlm.nih.gov/12270067/) • [2](https://www.iris.unina.it/retrieve/handle/11588/671433/114281/1-s2.0-S1470160X1630187X-main.pdf) |\n| Common test concentrations | 10, 100, and 1000 µg/mL for extracts; serial dilutions for purified compounds[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002) |\n| Organisms per vessel | Usually 10–20 nauplii per vial or microplate well[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002) • [4](https://doi.org/10.17504/protocols.io.yxmvm9q35l3p/v1) |\n| Sample requirement | About 2–20 mg or less of test material; no aseptic technique or special equipment[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002) |\n| Common cytotoxicity cut-off | \\( LC_{50} \\) < 30 µg/mL marks a crude extract as promising under NCI criteria[5](https://repository.up.ac.za/bitstreams/31aac3f1-55a6-4a4f-892d-3244378554f5/download) |\n| Controls | DMSO as solvent (negative) and potassium dichromate (K₂Cr₂O₇) as positive control[4](https://doi.org/10.17504/protocols.io.yxmvm9q35l3p/v1) |\n| Origin | Proposed for bioassay use by Michael, Thompson, and Abramovitz (Science, 1956); adapted to natural products by Meyer and colleagues (Planta Medica, 1982)[6](https://doi.org/10.1126/science.123.3194.464) • [7](https://doi.org/10.1055/s-2007-971236) |\n\n## How it works\n\nThe assay rests on a simple proxy: a compound or extract that kills half of a population of nauplius larvae at a low concentration is likely to be biologically toxic, and the \\( LC_{50} \\) ranks samples by potency. Hatched nauplii can survive up to 48 h without food because they still feed on their yolk sac, so mortality during a short exposure reflects the test substance rather than starvation, provided control mortality is low.[1](https://pubmed.ncbi.nlm.nih.gov/12270067/)\n\nValidation work indicates the test detects cytotoxic drugs with specific mechanisms of action, including protein synthesis inhibition, antimitotic activity, DNA binding, topoisomerase I inhibition, and caspase cascade interference.[8](https://www.benthamdirect.com/content/journals/cchts/10.2174/1386207326666230703095928) In a validation of 206 drugs from fifteen pharmacological categories tested in the microwell format with 24 h exposure, 26 showed \\( LC_{50} \\) values below 100 µM, most of them antineoplastics.[8](https://www.benthamdirect.com/content/journals/cchts/10.2174/1386207326666230703095928)\n\nHow strongly nauplius mortality predicts mammalian cytotoxicity is contested. In a blind comparison against known in vivo P-388-active antitumour agents from the US National Cancer Institute, the brine shrimp assay (p = 0.033) proved superior or equally as accurate as human solid tumor cell lines (p = 0.033–0.334).[9](https://doi.org/10.1002/pca.2800020303) By contrast, in marine natural products screening each brine shrimp bioassay alone detected activity in only 50% of species active against A-549 lung carcinoma and HT-29 colon carcinoma cells, rising to 75% when a lethality and a hatchability assay were used together.[1](https://pubmed.ncbi.nlm.nih.gov/12270067/)\n\n## How it is done\n\n1. **Hatch the cysts.** A published protocol adds 0.25 g of dehydrated Artemia cysts to 250 mL deionized water with 4.8 g iodized NaCl and incubates for 24 h at 25 °C with aeration and lighting.[4](https://doi.org/10.17504/protocols.io.yxmvm9q35l3p/v1) Most toxicity protocols use 48 h-old larvae at instar (developmental stage of a larva between molts) II–III, hatched at 18–28 °C and about 35‰ salinity, pH 7.5–9.0, with hatching light of 1000–4000 lux; instar I is less sensitive than instar II–III, so tests should start with nauplii of one age class.[2](https://www.iris.unina.it/retrieve/handle/11588/671433/114281/1-s2.0-S1470160X1630187X-main.pdf)\n2. **Prepare dilutions.** Extracts are most often tested at 10, 100, and 1000 µg/mL.[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002) In the 96-well format, 99 µL of nauplius suspension (15–20 nauplii per well) receives 1 µL of sample; samples run in triplicate and controls in quintuplicate, with DMSO as negative control and K₂Cr₂O₇ as positive control, incubated 24 h at 25 °C in the dark.[4](https://doi.org/10.17504/protocols.io.yxmvm9q35l3p/v1)\n3. **Score mortality.** A nauplius is counted dead when it shows no movement during an observation period; published criteria range from 5 s to 10 s to 30 s of immobility.[2](https://www.iris.unina.it/retrieve/handle/11588/671433/114281/1-s2.0-S1470160X1630187X-main.pdf) Control mortality above 10% invalidates the test in the Artoxkit M procedure[10](http://www.microbiotests.be/SOPs/Artoxkit%20M%20SOP%20-%20A5.pdf), and a 24-well variant using Abbott's correction, \\( M(\\%) = [(LC - LT)/LC] \\times 100 \\), likewise admits up to 10% control mortality.[11](https://pmc.ncbi.nlm.nih.gov/articles/PMC7952950/)\n4. **Calculate the LC50.** The standard approach is probit regression analysis (Finney, 1971) of percent mortality against log concentration, implemented in packages such as SPSS, R, Stata, and MatLab.[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002) • [12](https://link.springer.com/article/10.1186/s40199-015-0105-x)\n\n## Origin\n\nThe use of Artemia salina as a test organism for bioassay was proposed by A. S. Michael, C. G. Thompson, and M. Abramovitz in Science in 1956.[6](https://doi.org/10.1126/science.123.3194.464) Two ecotoxicology papers built the modern short-term test on that base: Paul Vanhaecke and colleagues proposed a short-term toxicity test with Artemia nauplii in 1981 in [Ecotoxicology](https://www.edgepedia.org/ecotoxicology) and Environmental Safety[13](https://doi.org/10.1016/0147-6513%2881%2990012-9), and R. B. Sleet and K. Brendel published improved methods for harvesting and counting synchronous nauplii populations for developmental toxicology in the same journal in 1983.[14](https://doi.org/10.1016/0147-6513%2883%2990082-9) The adaptation to natural products came from B. Meyer and colleagues, who published \"Brine Shrimp: A Convenient General Bioassay for Active Plant Constituents\" in Planta Medica in 1982, the paper usually cited as the Meyer bioassay.[7](https://doi.org/10.1055/s-2007-971236) Pablo Solis and colleagues miniaturized the assay into a 96-well microwell cytotoxicity format in Planta Medica in 1993.[15](https://doi.org/10.1055/s-2006-959661)\n\n## Variants\n\n**Meyer vial assay.** The original 1982 format uses small vials with 10–15 nauplii, the 10/100/1000 µg/mL concentration series, and a 24 h exposure.[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002)\n\n**Solis 96-well microwell assay.** The 1993 miniaturization cuts reagent and sample use, but later users reported systematically about 30% mortality in non-treated controls.[15](https://doi.org/10.1055/s-2006-959661) • [16](https://pharmacologyonline.silae.it/files/archives/2006/vol3/069.Molina-Salinas.pdf)\n\n**Molina-Salinas modified microplate assay.** A modified version of the Solis method reaches 100% nauplius viability up to 44 h after hatching; it uses 10 ± 1 nauplii in 100 µL per well, a K₂Cr₂O₇ series of 100.00–0.19 µg/mL, 24 h at 25 °C with shaking at 100 rpm, and PROBIT analysis.[16](https://pharmacologyonline.silae.it/files/archives/2006/vol3/069.Molina-Salinas.pdf)\n\n**Artoxkit M.** A standardized 24 h LC50 kit developed by the research team of Prof. Dr. G. Persoone at the State University of Ghent, Belgium, using instar II–III larvae of Artemia franciscana (formerly Artemia salina); cysts are hatched 30 h before the test at 25 °C under 3000–4000 lux, ten larvae are placed per well, and the dilution series runs from the concentration giving 100% mortality (\\( C_{1} \\)) down to 0.10 × \\( C_{1} \\).[10](http://www.microbiotests.be/SOPs/Artoxkit%20M%20SOP%20-%20A5.pdf)\n\n**Exposure time.** In the lethality test, maximum sensitivity was reached after 48 h of exposure, when nauplii have reached their second and third instar and show greatest sensitivity to test compounds[1](https://pubmed.ncbi.nlm.nih.gov/12270067/), while 24 h exposures remain the convention in most natural products work.[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002)\n\n## Applications\n\nThe test is used to screen plant extracts, marine natural products, fungi-derived materials, metallodrugs, nanoparticles, and pesticides. A screening of 226 methanol and water extracts from 74 Amazonian plant species tested at 500 µg/mL against Artemia franciscana nauplii found 8.8% (20 extracts) with more than 90% lethality.[17](https://acta.inpa.gov.br/fasciculos/33-1/PDF/v33n1a09.pdf)\n\nThreshold schemes differ by purpose. Under Meyer's index, extracts with \\( LC_{50} \\) < 1000 µg/mL are considered toxic and above 1000 µg/mL non-toxic; the Clarkson scheme grades 500–1000 µg/mL as low toxicity, 100–500 µg/mL as moderately toxic, and 0–100 µg/mL as highly toxic.[3](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002) Under National Cancer Institute criteria, a crude extract with \\( LC_{50} \\) below 30 µg/mL is considered promising for further purification; a podophyllotoxin reference standard gave an \\( LC_{50} \\) of 7 µg/mL, well within that cut-off.[5](https://repository.up.ac.za/bitstreams/31aac3f1-55a6-4a4f-892d-3244378554f5/download) Because it is fast and cheap, the assay also serves for bio-guided fractionation of natural product extracts.[18](https://www.jove.com/t/64472/lethality-bioassay-using-artemia-salina-l)\n\n## Limitations and alternatives\n\n**Solubility and solvent effects.** The assay requires a saline environment, which creates sample solubility problems, and the protocol's authors list low sensitivity among its limitations.[4](https://doi.org/10.17504/protocols.io.yxmvm9q35l3p/v1) DMSO, the usual solvent, is itself toxic at sufficient concentration, so solvent limits must be established; a 2024 study used DMSO as the test substance for exactly this purpose.[19](https://sage.cnpereading.com/doi/10.1177/02611929241242443)\n\n**Metabolic activation.** The brine shrimp assay is not predictive for compounds requiring metabolic activation, because brine shrimp lack the necessary cytochrome P-450 enzyme, a mechanistic source of false negatives.[5](https://repository.up.ac.za/bitstreams/31aac3f1-55a6-4a4f-892d-3244378554f5/download)\n\n**Interpretation limits.** Results cannot be extrapolated to mammalian toxicity, and the assay provides no information on mechanism of action.[5](https://repository.up.ac.za/bitstreams/31aac3f1-55a6-4a4f-892d-3244378554f5/download) Death definitions vary between 5, 10, and 30 s of immobility across published protocols, and Artemia toxicity testing still lacks official international standardization.[2](https://www.iris.unina.it/retrieve/handle/11588/671433/114281/1-s2.0-S1470160X1630187X-main.pdf) Endpoint sensitivity is also inconsistent across toxicants: for Cu ions the hatching-rate \\( EC_{50} \\) was at least 100 times below the analogous LC50, while for diatom extracts hatchability was less sensitive than larval mortality.[2](https://www.iris.unina.it/retrieve/handle/11588/671433/114281/1-s2.0-S1470160X1630187X-main.pdf)\n\n**Alternatives.** Compared with MTT cell-line assays, the brine shrimp test is cheaper and simpler but, in at least one head-to-head plant-extract study, less sensitive[5](https://repository.up.ac.za/bitstreams/31aac3f1-55a6-4a4f-892d-3244378554f5/download); for nanoparticles the two assays performed equivalently, with \\( LC_{50} \\) values correlating significantly with MTT \\( IC_{50} \\) values in L929 cells (\\( R^{2} = 0.72 \\), P = 0.000).[12](https://link.springer.com/article/10.1186/s40199-015-0105-x) A 2022 JoVE protocol positions the assay as a simple, quick, low-cost screen relative to in vitro cells, yeast strains, zebrafish, and rodents, performable without specific training.[18](https://www.jove.com/t/64472/lethality-bioassay-using-artemia-salina-l)\n\n**Recent developments.** A 2024 variables study found that a 25% to 30% deviation from standard buffer salinity, pH, and dissolved oxygen did not affect first-instar nauplius survival under assay conditions[19](https://sage.cnpereading.com/doi/10.1177/02611929241242443), and a 2024 optimization study identified continuous lighting, 30 °C, and 30 ppt salinity as the best cyst-hatching conditions for Vietnamese Artemia.[20](https://vjs.ac.vn/vjbio/article/view/18899) A 2026 review covers Artemia as a model for microplastic ingestion and trophic transfer; co-exposure of A. salina to PVC microplastics and pharmaceuticals or pesticides increased \\( LC_{50} \\) values, suggesting reduced acute toxicity from pollutant adsorption onto microplastic surfaces limiting bioavailability.[21](https://link.springer.com/article/10.1007/s11756-026-02166-9)\n\n## References\n\n1. [A comparison between two brine shrimp assays to detect in vitro cytotoxicity in marine natural products (BMC Biotechnology, 2002; PubMed record with abstract; full text at link.springer.com/article/10.1186/1472-6750-2-17)](https://pubmed.ncbi.nlm.nih.gov/12270067/)\n2. [A review of toxicity testing protocols and endpoints with Artemia spp. (Libralato et al., Ecological Indicators)](https://www.iris.unina.it/retrieve/handle/11588/671433/114281/1-s2.0-S1470160X1630187X-main.pdf)\n3. [Toxicological evaluation of the plant products using Brine Shrimp (Artemia salina L.) model (Hamidi, Jovanova & Kadifkova Panovska, 2014; mirror copy, publisher page not retrieved)](https://doi.org/10.33320/maced.pharm.bull.2014.60.01.002)\n4. [Screening natural products against Artemia salina v1 (protocols.io protocol, v1 dated May 28, 2025; mirror copy)](https://doi.org/10.17504/protocols.io.yxmvm9q35l3p/v1)\n5. [In vitro cytotoxicity tests of the developed extracts (Masoko, University of Pretoria thesis chapter, brine shrimp vs MTT Vero cells)](https://repository.up.ac.za/bitstreams/31aac3f1-55a6-4a4f-892d-3244378554f5/download)\n6. [A. S. MICHAEL, C. G. THOMPSON, M. ABRAMOVITZ (1956). Artemia salina as a Test Organism for Bioassay. Science.](https://doi.org/10.1126/science.123.3194.464)\n7. [B. Meyer and colleagues (1982). Brine Shrimp: A Convenient General Bioassay for Active Plant Constituents. Planta Medica.](https://doi.org/10.1055/s-2007-971236)\n8. [Understanding the Artemia Salina (Brine Shrimp) Test: Pharmacological Significance and Global Impact (Olmedo et al., Combinatorial Chemistry & High Throughput Screening, online 1 Mar 2024)](https://www.benthamdirect.com/content/journals/cchts/10.2174/1386207326666230703095928)\n9. [J. E. Anderson and colleagues (1991). A blind comparison of simple bench‐top bioassays and human tumour cell cytotoxicities as antitumor prescreens. Phytochemical Analysis.](https://doi.org/10.1002/pca.2800020303)\n10. [Artoxkit M Standard Operational Procedure (MicroBioTests Inc.)](http://www.microbiotests.be/SOPs/Artoxkit%20M%20SOP%20-%20A5.pdf)\n11. [Evaluation of Toxicity with Brine Shrimp Assay (methods protocol chapter, PMC; metallodrug applications)](https://pmc.ncbi.nlm.nih.gov/articles/PMC7952950/)\n12. [Artemia salina as a model organism in toxicity assessment of nanoparticles (DARU Journal of Pharmaceutical Sciences)](https://link.springer.com/article/10.1186/s40199-015-0105-x)\n13. [Proposal for a short-term toxicity test with Artemia nauplii (Ecotoxicology and Environmental Safety, 1981)](https://doi.org/10.1016/0147-6513%2881%2990012-9)\n14. [Improved methods for harvesting and counting synchronous populations of Artemia nauplii for use in developmental toxicology (Ecotoxicology and Environmental Safety, 1983)](https://doi.org/10.1016/0147-6513%2883%2990082-9)\n15. [Pablo Solis and colleagues (1993). A Microwell Cytotoxicity Assay usingArtemia salina(Brine Shrimp). Planta Medica.](https://doi.org/10.1055/s-2006-959661)\n16. [A modified microplate cytotoxicity assay with brine shrimp larvae (Artemia salina) (Molina-Salinas & Said-Fernández, Pharmacologyonline 2006)](https://pharmacologyonline.silae.it/files/archives/2006/vol3/069.Molina-Salinas.pdf)\n17. [Brine shrimp lethality assay of plant extracts from Amazonas State, Brazil (Acta Amazonica)](https://acta.inpa.gov.br/fasciculos/33-1/PDF/v33n1a09.pdf)\n18. [Lethality Bioassay Using Artemia salina L. (Princiotto, JoVE 2022, doi:10.3791/64472)](https://www.jove.com/t/64472/lethality-bioassay-using-artemia-salina-l)\n19. [Acute Toxicity Assays with the Artemia salina Model: Assessment of Variables (Salay et al., Alternatives to Laboratory Animals, 2024)](https://sage.cnpereading.com/doi/10.1177/02611929241242443)\n20. [Optimization of brine shrimp lethality test for in vivo toxicity evaluation of poisonous plant species collected from Quang Tri province (Academia Journal of Biology, 2024)](https://vjs.ac.vn/vjbio/article/view/18899)\n21. [Artemia genus as a tool for studies of microplastic ingestion and trophic transfer, a review (Biologia, Springer, 2026)](https://link.springer.com/article/10.1007/s11756-026-02166-9)\n\n---\n*Topic: Encyclopedia › Life and health › Human health and medicine*\n\n*Initially written Sep 29, 2026 · Edited: Oct 15, 2026*\n\n*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*\n\nLicense: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license\n", "same_as": [], "url": "https://www.edgepedia.org/brine-shrimp-lethality-test", "markdown_url": "https://www.edgepedia.org/brine-shrimp-lethality-test.md", "license": { "name": "Edgepedia Community License 1.0", "url": "https://www.edgepedia.org/edgepedia/license", "summary": "Free with credit, commercial use included. AI training is open to everyone. For other uses, organizations over USD 100M in revenue or 100M monthly users license separately.", "spdx": "LicenseRef-Edgepedia-Community-1.0" }, "credit": "\"Brine shrimp lethality test\", Edgepedia (EdgeChat), https://www.edgepedia.org/brine-shrimp-lethality-test. Edgepedia Community License 1.0.", "credit_md": "\"[Brine shrimp lethality test](https://www.edgepedia.org/brine-shrimp-lethality-test)\", Edgepedia (EdgeChat), [https://www.edgepedia.org/brine-shrimp-lethality-test](https://www.edgepedia.org/brine-shrimp-lethality-test). [Edgepedia Community License 1.0](https://www.edgepedia.org/edgepedia/license).", "credit_html": "\"Brine shrimp lethality test\", Edgepedia (EdgeChat), https://www.edgepedia.org/brine-shrimp-lethality-test. Edgepedia Community License 1.0.", "speakable": "The brine shrimp lethality test is a bench-top bioassay that measures the concentration of an extract or compound needed to kill half of laboratory-hatched brine shrimp larvae." }