A toxin is a naturally occurring poison[1] produced by metabolic activities of living cells or organisms.[2] They occur especially as proteins, often conjugated.[3] The term was first used by organic chemist Ludwig Brieger (1849–1919),[4] derived from toxic.

The Amanita muscaria mushroom, an iconic toxic mushroom.

Toxins can be small molecules, peptides, or proteins that are capable of causing disease on contact with or absorption by body tissues interacting with biological macromolecules such as enzymes or cellular receptors. They vary greatly in their toxicity, ranging from usually minor (such as a bee sting) to potentially fatal even at extremely low doses (such as botulinum toxin).[5][6]

Terminology

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Toxins are often distinguished from other chemical agents strictly based on their biological origin.[7]

Less strict understandings embrace naturally occurring inorganic toxins, such as arsenic.[8][9][10] Other understandings embrace synthetic analogs of naturally occurring organic poisons as toxins,[11] and may[12] or may not[13] embrace naturally occurring inorganic poisons. It is important to confirm usage if a common understanding is critical.

Toxins are a subset of toxicants. The term toxicant is preferred when the poison is man-made and therefore artificial.[14] The human and scientific genetic assembly of a natural-based toxin should be considered a toxin as it is identical to its natural counterpart.[15] The debate is one of linguistic semantics.

The word toxin does not specify method of delivery (as opposed to venom, a toxin delivered via a bite, sting, etc.). Poison is a related but broader term that encompasses both toxins and toxicants; poisons may enter the body through any means - typically inhalation, ingestion, or skin absorption. Toxin, toxicant, and poison are often used interchangeably despite these subtle differences in definition. The term toxungen has also been proposed to refer to toxins that are delivered onto the body surface of another organism without an accompanying wound.[16]

A rather informal terminology of individual toxins relates them to the anatomical location where their effects are most notable:

On a broader scale, toxins may be classified as either exotoxins, excreted by an organism, or endotoxins, which are released mainly when bacteria are lysed.

Biological

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The term "biotoxin" is sometimes used to explicitly confirm the biological origin as opposed to environmental or anthropogenic origins.[17][18] Biotoxins can be classified by their mechanism of delivery as poisons (passively transferred via ingestion, inhalation, or absorption across the skin), toxungens (actively transferred to the target's surface by spitting, spraying, or smearing), or venoms (delivered through a wound generated by a bite, sting, or other such action).[16] They can also be classified by their source, such as fungal biotoxins, microbial toxins, plant biotoxins, or animal biotoxins.[19][20]

Toxins produced by microorganisms are important virulence determinants responsible for microbial pathogenicity and/or evasion of the host immune response.[21]

Biotoxins vary greatly in purpose and mechanism, and can be highly complex (the venom of the cone snail can contain over 100 unique peptides, which target specific nerve channels or receptors).[22]

Biotoxins in nature have two primary functions:

Some of the more well known types of biotoxins include:

Weaponry

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Many living organisms employ toxins offensively or defensively. A relatively small number of toxins are known to have the potential to cause widespread sickness or casualties. They are often inexpensive and easily available, and in some cases it is possible to refine them outside the laboratory.[24] As biotoxins act quickly, and are highly toxic even at low doses, they can be more efficient than chemical agents.[24] Due to these factors, it is vital to raise awareness of the clinical symptoms of biotoxin poisoning, and to develop effective countermeasures including rapid investigation, response, and treatment.[19][25][24]

Environmental

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The term "environmental toxin" can sometimes explicitly include synthetic contaminants[26] such as industrial pollutants and other artificially made toxic substances. As this contradicts most formal definitions of the term "toxin", it is important to confirm what the researcher means when encountering the term outside of microbiological contexts.

Environmental toxins from food chains that may be dangerous to human health include:

Research

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In general, when scientists determine the amount of a substance that may be hazardous for humans, animals and/or the environment they determine the amount of the substance likely to trigger effects and if possible establish a safe level. In Europe, the European Food Safety Authority produced risk assessments for more than 4,000 substances in over 1,600 scientific opinions and they provide open access summaries of human health, animal health and ecological hazard assessments in their OpenFoodTox[37] database.[38][39] The OpenFoodTox database can be used to screen potential new foods for toxicity.[40]

The Toxicology and Environmental Health Information Program (TEHIP)[41] at the United States National Library of Medicine (NLM) maintains a comprehensive toxicology and environmental health web site that includes access to toxins-related resources produced by TEHIP and by other government agencies and organizations.[42] This web site includes links to databases, bibliographies, tutorials, and other scientific and consumer-oriented resources. TEHIP also is responsible for the Toxicology Data Network (TOXNET),[43] an integrated system of toxicology and environmental health databases that are available free of charge on the web.

TOXMAP is a Geographic Information System (GIS) that is part of TOXNET.[44] TOXMAP uses maps of the United States to help users visually explore data from the United States Environmental Protection Agency's (EPA) Toxics Release Inventory and Superfund Basic Research Programs.

See also

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References

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  1. ^ Harper, Douglas. "toxin". Online Etymology Dictionary.
  2. ^ "toxin – Definition from the Merriam-Webster Online Dictionary". Retrieved 13 December 2008.
  3. ^ "toxin" at Dorland's Medical Dictionary
  4. ^ Brade, Helmut (1999). Endotoxin in Health and Disease. CRC Press. ISBN 9780824719449. OCLC 41299257.
  5. ^ Gupta, PK (2018). Illustrated Toxicology with Study Questions. Elsevier Inc. ISBN 978-0-12-813213-5.
  6. ^ "Diagnosis and Treatment | Botulism". CDC. 1 June 2021. Archived from the original on 12 April 2022. Retrieved 12 April 2022.
  7. ^ Bennett, Joan W; Inamdar, Arati A (2015). "Are Some Fungal Volatile Organic Compounds (VOCs) Mycotoxins?". Toxins. 7 (9). Basel: 3785–3804. doi:10.3390/toxins7093785. PMC 4591661. PMID 26402705.
  8. ^ Goodman, Brenda. "Arsenic in Food: FAQ". WebMD. Retrieved 20 May 2022.
  9. ^ "Arsenic in your food - Our findings show a real need for federal standards for this toxin". Consumer Reports. 2012.
  10. ^ Beans, Carolyn (2021). "Keeping arsenic out of rice". Proceedings of the National Academy of Sciences. 118 (33). Bibcode:2021PNAS..11813071B. doi:10.1073/pnas.2113071118. PMC 8379988. PMID 34380741. S2CID 236989837.
  11. ^ "U.S. Code". Retrieved 20 May 2022. the term "toxin" means the toxic material or product of plants, animals, microorganisms ...or a recombinant or synthesized molecule...
  12. ^ "Module 1: Introduction to Toxicology" (PDF). Agency for Toxic Substances and Disease Registry. Retrieved 20 May 2022. arsenic, a toxic metal, may occur as a natural contaminant ... or ... as a by-product of industrial activities. If the second case is true, such toxic substances are referred to as toxicants, rather than toxins.
  13. ^ Goldblat, Jozef (30 June 1997). "The Biological Weapons Convention – An overview". Retrieved 20 May 2022. The Convention applies to all natural or artificially created toxins, "whatever their origin or method of production" (Article I). It thus covers toxins produced biologically, as well as those produced by chemical synthesis
  14. ^ "Difference Between Toxin and Toxicant (With Table)". 31 October 2021.
  15. ^ Murphy, J. R.; Bishai, W.; Williams, D.; Bacha, P.; Borowski, M.; Parker, K.; Boyd, J.; Waters, C.; Strom, T. B. (1987). "Genetic assembly and selective toxicity of diphtheria-toxin-related polypeptide hormone fusion proteins". Biochemical Society Symposium. 53: 9–23. PMID 2847744.
  16. ^ a b Nelsen, David R.; Nisani, Zia; Cooper, Allen M.; Fox, Gerad A.; Gren, Eric C. K.; Corbit, Aaron G.; Hayes, William K. (2014). "Poisons, toxungens, and venoms: Redefining and classifying toxic biological secretions and the organisms that employ them". Biological Reviews. 89 (2): 450–465. doi:10.1111/brv.12062. PMID 24102715. S2CID 207101679.
  17. ^ "biotoxin – Definition from the Merriam-Webster Online Dictionary". Retrieved 13 December 2008.
  18. ^ "biotoxin" at Dorland's Medical Dictionary
  19. ^ a b Editorial, Team (24 May 2021). "Toxins: Venom within Living Cells or Organisms". Unrevealed Files. Retrieved 17 July 2021.
  20. ^ "Biotoxins: What are Biotoxins?". www.biosciences-labs.bham.ac.uk. Retrieved 6 July 2023.
  21. ^ Proft T, ed. (2009). Microbial Toxins: Current Research and Future Trends. Caister Academic Press. ISBN 978-1-904455-44-8.
  22. ^ Robinson, Samuel D; Norton, Raymond S (17 December 2014). "Conotoxin Gene Superfamilies". Marine Drugs. 12 (12): 6058–6101. doi:10.3390/md12126058. PMC 4278219. PMID 25522317.
  23. ^ Dorland's Illustrated Medical Dictionary (32nd ed.). Philadelphia, PA: Saunders/Elsevier. 2012. p. 1236. ISBN 978-1-4160-6257-8.
  24. ^ a b c Janik, Edyta; Ceremuga, Michal; Saluk-Bijak, Joanna; Bijak, Michal (8 March 2019). "Biological Toxins as the Potential Tools for Bioterrorism". International Journal of Molecular Sciences. 20 (5): 1181. doi:10.3390/ijms20051181. ISSN 1422-0067. PMC 6429496. PMID 30857127.
  25. ^ Płusa, Tadeusz (September 2015). "[Toxins as a biological weapon]". Polski Merkuriusz Lekarski. 39 (231): 131–133. ISSN 1426-9686. PMID 26449572.
  26. ^ Grigg J (March 2004). "Environmental toxins; their impact on children's health". Archives of Disease in Childhood. 89 (3): 244–50. doi:10.1136/adc.2002.022202. PMC 1719840. PMID 14977703.
  27. ^ Vale C, Alfonso A, Vieytes MR, Romarís XM, Arévalo F, Botana AM, Botana LM (March 2008). "In vitro and in vivo evaluation of paralytic shellfish poisoning toxin potency and the influence of the pH of extraction". Analytical Chemistry. 80 (5): 1770–6. doi:10.1021/ac7022266. PMID 18232710.
  28. ^ Oikawa H, Fujita T, Saito K, Satomi M, Yano Y (2008). "Difference in the level of paralytic shellfish poisoning toxin accumulation between the crabs Telmessus acutidens and Charybdis japonica collected in Onahama, Fukushima Prefecture". Fisheries Science. 73 (2): 395–403. doi:10.1111/j.1444-2906.2007.01347.x. S2CID 22926782.
  29. ^ Abouabdellah R, Taleb H, Bennouna A, Erler K, Chafik A, Moukrim A (April 2008). "Paralytic shellfish poisoning toxin profile of mussels Perna perna from southern Atlantic coasts of Morocco". Toxicon. 51 (5): 780–6. Bibcode:2008Txcn...51..780A. doi:10.1016/j.toxicon.2007.12.004. PMID 18237757.
  30. ^ Wang L, Liang XF, Zhang WB, Mai KS, Huang Y, Shen D (November 2009). "Amnesic shellfish poisoning toxin stimulates the transcription of CYP1A possibly through AHR and ARNT in the liver of red sea bream Pagrus major". Marine Pollution Bulletin. 58 (11): 1643–8. Bibcode:2009MarPB..58.1643W. doi:10.1016/j.marpolbul.2009.07.004. PMID 19665739.
  31. ^ Wang L, Vaquero E, Leão JM, Gogo-Martínez A, Rodríguez Vázquez JA (2001). "Optimization of conditions for the liquid chromatographic-electrospray lonization-mass spectrometric analysis of amnesic shellfish poisoning toxins". Chromatographia. 53 (1): S231–35. doi:10.1007/BF02490333. S2CID 97937094.
  32. ^ Mouratidou T, Kaniou-Grigoriadou I, Samara C, Kouimtzis T (August 2006). "Detection of the marine toxin okadaic acid in mussels during a diarrhetic shellfish poisoning (DSP) episode in Thermaikos Gulf, Greece, using biological, chemical and immunological methods". The Science of the Total Environment. 366 (2–3): 894–904. Bibcode:2006ScTEn.366..894M. doi:10.1016/j.scitotenv.2005.03.002. PMID 16815531.
  33. ^ Doucet E, Ross NN, Quilliam MA (September 2007). "Enzymatic hydrolysis of esterified diarrhetic shellfish poisoning toxins and pectenotoxins". Analytical and Bioanalytical Chemistry. 389 (1): 335–42. doi:10.1007/s00216-007-1489-3. PMID 17661021. S2CID 21971745.
  34. ^ Poli MA, Musser SM, Dickey RW, Eilers PP, Hall S (July 2000). "Neurotoxic shellfish poisoning and brevetoxin metabolites: a case study from Florida". Toxicon. 38 (7): 981–93. doi:10.1016/S0041-0101(99)00191-9. PMID 10728835.
  35. ^ Morohashi A, Satake M, Murata K, Naoki H, Kaspar HF, Yasumoto T (1995). "Brevetoxin B3, a new brevetoxin nalog isolated from the greenshell mussel perna canaliculus involved in neurotoxic shellfish poisoning in new zealand". Tetrahedron Letters. 36 (49): 8995–98. doi:10.1016/0040-4039(95)01969-O.
  36. ^ Morohashi A, Satake M, Naoki H, Kaspar HF, Oshima Y, Yasumoto T (1999). "Brevetoxin B4 isolated from greenshell mussels Perna canaliculus, the major toxin involved in neurotoxic shellfish poisoning in New Zealand". Natural Toxins. 7 (2): 45–8. doi:10.1002/(SICI)1522-7189(199903/04)7:2<45::AID-NT34>3.0.CO;2-H. PMID 10495465.
  37. ^ "Chemical hazards data - OpenFoodTox". European Food Safety Authority. Retrieved 27 October 2019.
  38. ^ Dorne JL, Richardson J, Kass G, Georgiadis N, Monguidi M, Pasinato L, Cappe S, Verhagen H, Robinson T (January 2017). "OpenFoodTox: EFSA's open source toxicological database on chemical hazards in food and feed". EFSA Journal. 15 (1): e15011. doi:10.2903/j.efsa.2017.e15011. PMC 7009813. PMID 32625280.
  39. ^ Reilly L, Serafimova R, Partosch F, Gundert-Remy U, Cortiñas Abrahantes J, Dorne JM, Kass GE (October 2019). "Testing the thresholds of toxicological concern values using a new database for food-related substances". Toxicology Letters. 314: 117–123. doi:10.1016/j.toxlet.2019.07.019. PMID 31325634.
  40. ^ Pearce JM, Khaksari M, Denkenberger D (April 2019). "Preliminary Automated Determination of Edibility of Alternative Foods: Non-Targeted Screening for Toxins in Red Maple Leaf Concentrate". Plants. 8 (5): 110. doi:10.3390/plants8050110. PMC 6571818. PMID 31027336.
  41. ^ "Environmental Health and Toxicology Information". National Library of Medicine. Archived from the original on 1 September 2018. Retrieved 29 September 2010.
  42. ^ Fonger GC, Stroup D, Thomas PL, Wexler P (January 2000). "TOXNET: A computerized collection of toxicological and environmental health information". Toxicology and Industrial Health. 16 (1): 4–6. Bibcode:2000ToxIH..16....4F. doi:10.1177/074823370001600101. PMID 10798381. S2CID 34029729.
  43. ^ "TOXNET". toxnet.nlm.nih.gov. Archived from the original on 14 May 2019. Retrieved 29 September 2010.
  44. ^ Hochstein C, Szczur M (24 July 2006). "TOXMAP: a GIS-based gateway to environmental health resources". Medical Reference Services Quarterly. 25 (3): 13–31. doi:10.1300/J115v25n03_02. PMC 2703818. PMID 16893844.
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