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INTRODUCTION TO VETERINARY 
TOXICOLOGY 
Dr. Sindhu K. 
MVSc scholar, Dept of VPT, 
COVAS, Pookode.
POISON 
A POISON is any substance which, when ingested, inhaled, absorbed, or when 
applied to, injected into, or develope...
ETYMOLOGY 
TOXIN 
Toxon (Greek)  for bow & arrow 
Toxicon  poison dipped arrow 
POISON 
Poi  to drink & becoming pot...
I. TOXICOLOGY IN ANTIQUITY 
Medicine is an ancient science. 
The use of plant & animals substances 
to heal disease is a...
PREHISTORIC MAN 
The historical development 
of toxicology began with early 
cave dwellers who recognized 
poisonous plan...
FIRST “MENTION” (3100-3000 B.C.) 
Egyptian pharaoh of the 1st dynasty 
United the lower & upper Egypt. 
Founded Memphis...
MESOPOTAMIA 
The development of human civilization 
is thought to have originated in the 
fertile crescent which is now o...
The code of Hammurabi was 
chiseled into stone, providing 
evidence for future generations 
of the expected behavior of 
...
Bites & stings from venomous animals occurred & were 
treated with scarification, bloodletting (cut & suction), the use 
...
EGYPT 
The Egyptian civilization developed at 
approximately the same time as those of 
Babylon & Assyria. 
Writing pape...
One Egyptian picture story depicts a 
puffer fish, Tetraodon sp. Which was 
recognized as a poisonous fish. 
The Smith p...
1STWRITTEN RECORD (2700 B. C.) 
Shen Nung Pen ts’ao ching – divine 
Husbandman’s material medica. 
Contained list of poi...
THE VEDAS (900 B. C.) 
Hindu scriptures  ATHARVA 
VEDA 
• First Indian text dealing with 
medicine 
• Mention of poisoni...
ISRAEL 
Ancient Hebrew people were guided in every 
aspect of their lives by the old Testament. 
Strict dietary laws wer...
• One of the plagues pronounced on the Egyptians by Moses was the 
earliest account of red tide caused by dinoflagellates ...
CHINA 
Ancient & modern Chinese medicine rely 
heavily on natural products for healing 
disease (herbal medicine, rhinoce...
GREECE (500 B.C TO A.D. 500) 
Modern medicine had its genesis in the Greek civilization, from 500 B.C to A.D. 
500. 
Med...
• Homer (600 B.C.) Odysseus obtains poison for his arrows
HIPPOCRATES (460 – 355 B.C). 
The father of medicine. 
Introduced principles of clinical toxicology 
related to bioavail...
ARISTOTLE (384 – 322 B.C.) 
Aristotle (384 – 322 B.C.) knew of the 
stinging of jellyfish. 
Alexander the great forbade ...
THEOPHRASTUS 
(370-286 B. C.) 
Born in Eresus, on the island of Lesbos. 
Student of Aristotle. 
Authored De Historia Pl...
SOCRATES (469 – 399 B.C.) 
Was a classical Greek (Athenian) philosopher credited as one of the 
founders ofWestern philos...
DEMOSTHENES (385 – 
322 B. C.) 
Demosthenes was a prominent Greek 
statesman and orator of ancient Athens. 
His famous s...
NICANDER (197 – 130 B. C.) 
Nicander of Colophon (2nd century B.C.), Greek poet, physician and grammarian, was 
born at C...
ALEXIPHARMACA: THE WORKS OF NICANDER
CLEOPATRA (LATE 69 BC– AUGUST 12, 30 BC) 
Cleopatra VII Philopator , known to history as Cleopatra, 
was the last active ...
MITHRIDATES (120 – 63 B.C.) 
The king of Pontus, Mithridates VI, 
was one of the 1st to advance the art & science of pois...
FIRST POISON LAW: CIRCA 
82 B. C. 
Dictator Lucius Cornelius Sulla – Lex 
Cornelia. 
Growing conspiracy to kill men for ...
PEDANIUS DIOSCORIDES (A.D. 50 - 100) 
• was a physician, pharmacologist and 
botanist, the author of De Materia 
Medica—a ...
AQUA TOFFANA 
Arsenic containing perfumes were 
prepared by lady named Toffana 
Such cosmetics are termed Aqua 
toffana,...
ARUM MACULATUM 
Arum or Cuckoo-Pint 
Ancient physicians called this plant  the 
Drakontaia Mikre/ “small dragon” becaus...
PLINY THE ELDER (A.D. 29 - 79) 
wrote the classic Naturalis Historcia, a 
comprehensive encyclopedia of the 
natural worl...
NERO (37 – 68 A. D.) 
Mother (Agrippina) consults with skilled 
poisoner (Locusta) to poison Emperor 
Claudius such that ...
GALEN (129 – 199 A. D.) 
Claudius Galen of Pergamum 
Greek physician, Philosopher 
Believed therapeutics should be in t...
ISLAMIC COUNTRIES 
Moslem countries provided little 
original contribution to the field of 
toxicology until a Persian by...
II. MEDIEVAL PERIOD 
The collapse of the Roman empire 
ushered in a period of intellectual 
stagnation(Dark Ages). 
Many...
MOSES BEN MAIMON (1135- 
1204 AD) 
was a preeminent medieval Spanish, 
Sephardic Jewish philosopher, 
astronomer and one ...
With the Renaissance came 
the age of scientific inquiry, & 
numerous naturalists, 
physicians, missionaries, 
explorers,...
EARLY RENAISSANCE 
Little was known about the 
nature of the venoms/poisons. 
The provincialism of European & 
Mediterra...
Captain James Cook of H.M.S. Resolution nearly died of tetradotoxin 
poisoning after consuming fish in New Caledonia.
CATHERINE DE MEDICI 
In France, a lady along with 
Marchioness de Brinvillers used the 
most effective poisons on sick & ...
CARL VON LINNE (LINNAEUS) 
The Swedish naturalist, made a 
monumental contribution to biology & 
toxicology. 
He introdu...
PARACELSUS (1493 - 1541) 
Famous German physician who 
distinguished a poison from a remedy. 
He gave the great statemen...
IV. MODERN ERA OF TOXICOLOGY 
Relatively young science based on the scientific works carried out by 
numerous dedicated r...
FRIEDRICH SERTURNER (1783- 
1841) 
German pharmacologist who isolated the 
specific narcotic substance from opium & named...
M. J. B. ORFILA (1787-1853) 
Spanish physician considered as ‘Father of Toxicology’. 
He established toxicology as a dis...
FATHER OF 
TOXICOLOGY
FRANCOIS MAGENDIE (1783- 
1855) 
A pioneer French experimental physiologist & 
toxicologist who researched the different ...
19TH CENTURY 
Scientific disciplines began to 
proliferate viz., chemistry, 
physiology, pharmacology & 
toxicology. 
Sc...
Biologists studied natural history of plant & animals. 
Anatomists dissected & described the venom apparatus. 
Biochemi...
• The field of toxicology became so broad that scientists began to 
narrow their fields of interest further: into plant po...
JAMES MARSH 1832 
Developed the first chemical test for 
identifying arsenic, called Marsh test. 
Hugo Reinsch 1842 
Dev...
THEODORE G. WORMLEY (1869) 
Wrote the 1st 
American book - 
‘Microchemistry 
of poisons’ , 
dedicated to 
poisons.
LOUIS LEWIN (1854-1929) 
A German scientist who took up the task of 
classifying drugs & plants in accordance to 
their p...
FDA, 1930. 
• Food & Drug Administration was founded to regulate the content 
and safety of consumer drugs & foods.
PAUL HERMANN MULLER (1899-1965) 
He discovered the insecticidal properties of 
DDT in 1939 & along with his team 
introdu...
GERHARD SCHRADER (1903-1990) 
A German chemist who accidentally developed 
the toxic nerve agents viz., sarin, tabun, som...
K. K. CHEN (1934) 
• Demonstrated antagonist effect of 
sodium nitrite & sodium 
thiosulphate in cyanide poisoning.
R. A. PETERS, L. A. STOCKEN, & R. H. S. THOMPSON. 
(1945) 
• Developed dimercaprol as an antidote to arsenic containing wa...
THALIDOMIDE DISASTER 1959-1960’s 
 was first marketed in 1957 in West Germany under the trade-name Contergan. 
 The Germ...
RACHEL CARSON (1962) 
• Started crusade against the use of DDT & published the great book 
“silent spring”.
LOUIS J. CASARETT & JOHN DOULL (1971) 
• published the 1st modern 
Toxicology textbook titled 
“Toxicology: The basic 
sci...
NUCLEAR ACCIDENTS AT THREE MILE ISLAND NEAR 
HARRISBURG, PENNSYLVANIA. (1979) 
• The accident began with failures in the n...
BHOPAL GAS DISASTER, (1984) 
 occurred due to accidental release of methyl isocyanate killing 
thousands & injuring hundr...
CHERNOBYL NUCLEAR POWER PLANT ACCIDENT (1986) 
Occurred in Soviet Union spreading radioactive debris over several 
countr...
LATTER HALF OF THE 20TH CENTURY 
A noteworthy achievements led to better understandings of the ecology 
of poisons & veno...
COEVOLUTION?? 
Plants & herbivorous animals (insects) coevolved in an adversarial 
relationship. 
Plant population devel...
The case of coevolution of plants & insects 
is easily demonstrated, while evidence for 
plant/mammal coevolution is more...
The progenitors of large, wild herbivorous animals viz., 
cattle/horse/bison/antelope didn’t appear until 40 million 
year...
Even though mammalian herbivores may not have coevolved with 
plants like insects, there is sound evidence that plant (di...
ANIMAL TOXIN ECOLOGY 
Animal toxin & venoms are used to obtain 
• Food 
• Deter predation 
• Regulate population 
• Aid in...
CONCLUSIONS 
Poisons & venoms have served a vital role in the evolution of plants & 
animals. 
• The pharmacological effe...
DISCUSSIONS
REFERENCES. 
Murray E. Fowler: Veterinary Zootoxicology. (CRC press). 
Sandhu H. S. & Brar R. S: Text Book of Veterinary...
Introduction to Veterinary General toxicology
Introduction to Veterinary General toxicology
Introduction to Veterinary General toxicology
Introduction to Veterinary General toxicology
Introduction to Veterinary General toxicology
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Introduction to Veterinary General toxicology

quick reference for general toxicology history and co-evolution of plants & animals along with environment since the dawn of the evolution.

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Introduction to Veterinary General toxicology

  1. 1. INTRODUCTION TO VETERINARY TOXICOLOGY Dr. Sindhu K. MVSc scholar, Dept of VPT, COVAS, Pookode.
  2. 2. POISON A POISON is any substance which, when ingested, inhaled, absorbed, or when applied to, injected into, or developed with in the body, in relatively small amounts, may cause damage to body structure or disturbance of function through its chemical action. Poison & poisonous animals have been of interest to humans since the dawn of creation. Toxicology = the study of poisons. Bio toxicology = the study of poisons from living organisms. Zoo toxicology = the study of poisonous animals.
  3. 3. ETYMOLOGY TOXIN Toxon (Greek)  for bow & arrow Toxicon  poison dipped arrow POISON Poi  to drink & becoming potare in Latin (potion)  Venomous nature derived from wen to win, & led to venus/venerate through “love potions” (venin)
  4. 4. I. TOXICOLOGY IN ANTIQUITY Medicine is an ancient science. The use of plant & animals substances to heal disease is as old as the diseases themselves. Early practitioners of medicine were priests or magicians/physicians, & it was commonly thought that guilty of a crime would be affected by a poison.
  5. 5. PREHISTORIC MAN The historical development of toxicology began with early cave dwellers who recognized poisonous plants and animals and used their extracts for HUNTING or in warfare.
  6. 6. FIRST “MENTION” (3100-3000 B.C.) Egyptian pharaoh of the 1st dynasty United the lower & upper Egypt. Founded Memphis as capital Founder of many new cults & temples Cultivated & studied effects of poisons & medicinal plants.
  7. 7. MESOPOTAMIA The development of human civilization is thought to have originated in the fertile crescent which is now occupied by Iraq, Syria, Israel & Egypt, but was known as Babylon & Assyria historically. Medicine had its beginnings in this region.
  8. 8. The code of Hammurabi was chiseled into stone, providing evidence for future generations of the expected behavior of physicians.
  9. 9. Bites & stings from venomous animals occurred & were treated with scarification, bloodletting (cut & suction), the use of incantations, & a procedure called Cupping Cupping = use of animal horn to neutralize the poison.
  10. 10. EGYPT The Egyptian civilization developed at approximately the same time as those of Babylon & Assyria. Writing paper was manufactured from the papyrus plant, Cyperus papyrus-sedge family- Cyperaceae, which is reed like plant that grows in shallow water. Modern humans have learned of the prescriptions & medicine used for treating ailments through various papyri.
  11. 11. One Egyptian picture story depicts a puffer fish, Tetraodon sp. Which was recognized as a poisonous fish. The Smith papyrus (1600 B.C.) lists charms for use against snakebite. The Hearst Medical papyrus provides numerous prescriptions, some of which were prescribed for animal bites.
  12. 12. 1STWRITTEN RECORD (2700 B. C.) Shen Nung Pen ts’ao ching – divine Husbandman’s material medica. Contained list of poisonous & medicinal plants and drugs Enlisted the effects & antidotes viz., iodine, opium, cannabis, mercury.
  13. 13. THE VEDAS (900 B. C.) Hindu scriptures  ATHARVA VEDA • First Indian text dealing with medicine • Mention of poisoning for use in warfare I. Arrows with ducts II. Castor bean poison III. Poisoned nets IV. Hook traps
  14. 14. ISRAEL Ancient Hebrew people were guided in every aspect of their lives by the old Testament. Strict dietary laws were imposed on the people, presumably to maintain health & prevent disease. Eg: trichinosis in pork. Early Israelites were admonished not to eat items from the water that had neither fins nor scales (Deuteronomy 14:9-10). Fish with neither of these structures tend to be the most poisonous & thus should be avoided.
  15. 15. • One of the plagues pronounced on the Egyptians by Moses was the earliest account of red tide caused by dinoflagellates (the water turned to blood, killing all the fish– Exodus 7:19-20)
  16. 16. CHINA Ancient & modern Chinese medicine rely heavily on natural products for healing disease (herbal medicine, rhinoceros horn & gall bladders). Medical practitioners recognized scale less fish as being toxic & 1st report of ciguatera toxicosis was described from ingestion of yellowtail tuna (ca A.D. 700)
  17. 17. GREECE (500 B.C TO A.D. 500) Modern medicine had its genesis in the Greek civilization, from 500 B.C to A.D. 500. Medicine became separated from myth, magic, & religion.
  18. 18. • Homer (600 B.C.) Odysseus obtains poison for his arrows
  19. 19. HIPPOCRATES (460 – 355 B.C). The father of medicine. Introduced principles of clinical toxicology related to bioavailability of toxicants. knew of the toxicity of sea urchin spines. Oath to ‘not poison’. “to please no one will I prescribe a deadly drug nor give advice which may cause his death”.
  20. 20. ARISTOTLE (384 – 322 B.C.) Aristotle (384 – 322 B.C.) knew of the stinging of jellyfish. Alexander the great forbade his troops to eat fish, presumably because of concern for toxicity.
  21. 21. THEOPHRASTUS (370-286 B. C.) Born in Eresus, on the island of Lesbos. Student of Aristotle. Authored De Historia Plantarum. Included numerous references to poison plants. Considered as “The Father of Botany”.
  22. 22. SOCRATES (469 – 399 B.C.) Was a classical Greek (Athenian) philosopher credited as one of the founders ofWestern philosophy. Execution/Suicide death of by hemlock (Conium maculatum). The term, "Socratic paradox" can also refer to a self-referential paradox, originating in Socrates' utterance, as “I know that I know nothing”. • No one desires evil. • No one errs or does wrong willingly or knowingly. • Virtue—all virtue—is knowledge. • Virtue is sufficient for happiness.
  23. 23. DEMOSTHENES (385 – 322 B. C.) Demosthenes was a prominent Greek statesman and orator of ancient Athens. His famous saying – “ All speech is vain & empty unless it be accompanied by action.” Suicide by poisoned pen.
  24. 24. NICANDER (197 – 130 B. C.) Nicander of Colophon (2nd century B.C.), Greek poet, physician and grammarian, was born at Claros (Ahmetbeyli in modern Turkey), near Colophon, where his family held the hereditary priesthood of Apollo. He flourished under Attalus III of Pergamum. He wrote a number of works both in prose and verse, of which two survive complete. The longest, Theriaca, is a hexameter poem (958 lines) on the nature of venomous animals and the wounds which they inflict. The other, Alexipharmaca, consists of 630 hexameters treating of poisons and their antidotes. The works of Nicander were praised by Cicero (De oratore, i. 16), imitated by Ovid and Lucan, and frequently quoted by Pliny and other writers (e. g. Tertullian in De Scorpiace, I, 1).
  25. 25. ALEXIPHARMACA: THE WORKS OF NICANDER
  26. 26. CLEOPATRA (LATE 69 BC– AUGUST 12, 30 BC) Cleopatra VII Philopator , known to history as Cleopatra, was the last active pharaoh of Ancient Egypt, only shortly survived by her son, Caesarion as pharaoh. The ancient sources, particularly the Roman ones, are in general agreement that Cleopatra killed herself by inducing an Egyptian cobra to bite her.  The oldest source is Strabo, says that there are two stories: that she applied a toxic ointment, or that she was bitten by an asp on her breast. Several Roman poets, writing within ten years of the event, all mention bites by two asps, as does Florus, a historian, some 150 years later. Velleius, sixty years after the event, also refers to an asp.
  27. 27. MITHRIDATES (120 – 63 B.C.) The king of Pontus, Mithridates VI, was one of the 1st to advance the art & science of poisons & antidotes. He experimented to attempt development of a universal antidote, including numerous substances in his concoctions, which were called “mithridates”. Even today, the term “mithridates” or “shotgun treatment” is used to describe a situation in which multiple drugs are prescribed, in the hope that one of the drugs will be effective against the ailment suffered by the patient. Mithridates philosophy was followed for many centuries in treating all kinds of diseases, including poisoning & envenomination.
  28. 28. FIRST POISON LAW: CIRCA 82 B. C. Dictator Lucius Cornelius Sulla – Lex Cornelia. Growing conspiracy to kill men for profit. Provisions for both the poisoner and the provider of the poison.
  29. 29. PEDANIUS DIOSCORIDES (A.D. 50 - 100) • was a physician, pharmacologist and botanist, the author of De Materia Medica—a 5-volume encyclopedia about herbal medicine and related medicinal substances (a pharmacopeia), which served the medical profession for 1600 years. • Classified poisons for 1st time into plants, minerals / animal poisons. • He described treatment for various marine animal intoxications, including the stingray & “sea vipers”.
  30. 30. AQUA TOFFANA Arsenic containing perfumes were prepared by lady named Toffana Such cosmetics are termed Aqua toffana, were used to kill the foes.
  31. 31. ARUM MACULATUM Arum or Cuckoo-Pint Ancient physicians called this plant  the Drakontaia Mikre/ “small dragon” because central stalk resembles a serpant. According to Dioscorides, its shape revealed its purpose as an antidote for snakebite. Rubbing one’s hands with Arum root was supposed to make one unbiteable.
  32. 32. PLINY THE ELDER (A.D. 29 - 79) wrote the classic Naturalis Historcia, a comprehensive encyclopedia of the natural world, which was the natural history “bible” until the Renaissance. Pliny wrote one section devoted to De Venenalis Marinus (marine poisons).
  33. 33. NERO (37 – 68 A. D.) Mother (Agrippina) consults with skilled poisoner (Locusta) to poison Emperor Claudius such that her son from a previous marriage (Nero), seize power & cleverly poisoned step-brother Brittanicus. Used slaves as food tasters to differentiate poisonous mushrooms from edible ones.
  34. 34. GALEN (129 – 199 A. D.) Claudius Galen of Pergamum Greek physician, Philosopher Believed therapeutics should be in the hands of physicians rather than herbalists Galena : a remedy/anti-dote for poison
  35. 35. ISLAMIC COUNTRIES Moslem countries provided little original contribution to the field of toxicology until a Persian by the name of Geber ibn Hajan (ca. A.D. 750 - 760) wrote a long treatise on poisons, including venoms & their antidotes.
  36. 36. II. MEDIEVAL PERIOD The collapse of the Roman empire ushered in a period of intellectual stagnation(Dark Ages). Many of us have the impression that nothing was accomplished in the science during this time; but in reality, the printing press & gun powder, among other things, were invented during dark ages. A few physicians wrote about venomous animals, but little original toxicologic thought arose in this era.
  37. 37. MOSES BEN MAIMON (1135- 1204 AD) was a preeminent medieval Spanish, Sephardic Jewish philosopher, astronomer and one of the most prolific and influential Torah scholars and physicians of the Middle Ages. Wrote a book “Poisons and Their Antidotes” describing the treatment of poisoning from insects, snakes & mad dogs.
  38. 38. With the Renaissance came the age of scientific inquiry, & numerous naturalists, physicians, missionaries, explorers, & historians began to document the prevalence of intoxication of humans by animals & plants.
  39. 39. EARLY RENAISSANCE Little was known about the nature of the venoms/poisons. The provincialism of European & Mediterranean country writers was overcome as explorers returned from far-flung expeditions with factual & fanciful tales of the tropical region of the world.
  40. 40. Captain James Cook of H.M.S. Resolution nearly died of tetradotoxin poisoning after consuming fish in New Caledonia.
  41. 41. CATHERINE DE MEDICI In France, a lady along with Marchioness de Brinvillers used the most effective poisons on sick & poor people in the name of treating them & killed several people!! Catherine was given the tittle of ‘La Voisine’ Later she was convicted of many poisonings including over 2000 infants.
  42. 42. CARL VON LINNE (LINNAEUS) The Swedish naturalist, made a monumental contribution to biology & toxicology. He introduced the system of binomial naming & classification of plants & animals, Systema Naturae, 1758. His system enabled scientists from around the world to communicate about plants & animals without having to know all the local, common names.
  43. 43. PARACELSUS (1493 - 1541) Famous German physician who distinguished a poison from a remedy. He gave the great statement “All substances are poisons; there is none which is not poison. The right dose differentiates a poison & a remedy”. This statement laid the foundation of the modern concept of the ‘dose-response relationship’ & the ‘therapeutic index’ developed later.
  44. 44. IV. MODERN ERA OF TOXICOLOGY Relatively young science based on the scientific works carried out by numerous dedicated researchers & scientists. It’s the outcome of rational thinking, experimentation, relationship between dose & therapeutics as compared with toxic, and response to chemicals.
  45. 45. FRIEDRICH SERTURNER (1783- 1841) German pharmacologist who isolated the specific narcotic substance from opium & named it morphine after Morpheus, the Roman god of sleep. Its isolation allowed physicians to prescribe painkiller's in regulated dose.
  46. 46. M. J. B. ORFILA (1787-1853) Spanish physician considered as ‘Father of Toxicology’. He established toxicology as a discipline distinct from others & defined toxicology as the study of poisons. In 1813, he published the results of many toxicological experiments under the tittle of “toxicologic Generale” He advocated the necessity of chemical analysis for medicolegal cases. Orfila became very proficient in the chemistry of crime scene investigation & was an early promoter of chemical evidence in the courtroom.
  47. 47. FATHER OF TOXICOLOGY
  48. 48. FRANCOIS MAGENDIE (1783- 1855) A pioneer French experimental physiologist & toxicologist who researched the different motor functions of the body in relation to the spine, as well as nerves within it. He also described the effects & uses of morphine, emetine, quinine, strychnine, & other alkaloids, for which he is also called the “Father of Experimental Pharmacology”.
  49. 49. 19TH CENTURY Scientific disciplines began to proliferate viz., chemistry, physiology, pharmacology & toxicology. Scientific meetings provided a forum for expounding theories, & professional publications spread information throughout the world.
  50. 50. Biologists studied natural history of plant & animals. Anatomists dissected & described the venom apparatus. Biochemists studied venoms & poisons, & much was learned in the 19th century about chemical structure and pharmacologic effects. Textbooks on toxicology were published in German, French, Japanese, English & other languages. Toxicology became a required course in most medical & veterinary schools
  51. 51. • The field of toxicology became so broad that scientists began to narrow their fields of interest further: into plant poisoning, marine biotechnology, or pesticide toxicology. • Scientists of the 20th century continued & intensified the study of poisons.
  52. 52. JAMES MARSH 1832 Developed the first chemical test for identifying arsenic, called Marsh test. Hugo Reinsch 1842 Developed a series of tests for detecting arsenic & mercury.
  53. 53. THEODORE G. WORMLEY (1869) Wrote the 1st American book - ‘Microchemistry of poisons’ , dedicated to poisons.
  54. 54. LOUIS LEWIN (1854-1929) A German scientist who took up the task of classifying drugs & plants in accordance to their psychological effects. He also published many articles & books dealing with toxicology of methyl alcohol, ethyl alcohol, chloroform, opium, & other chemicals. His important publications are; Toxicologist’s view of world history. A text book of toxicology.
  55. 55. FDA, 1930. • Food & Drug Administration was founded to regulate the content and safety of consumer drugs & foods.
  56. 56. PAUL HERMANN MULLER (1899-1965) He discovered the insecticidal properties of DDT in 1939 & along with his team introduced other chlorinated hydrocarbon insecticides. He was awarded the Nobel prize in physiology/medicine in 1948 for his discovery of “the high efficiency of DDT as a contact poison against several arthropods”.
  57. 57. GERHARD SCHRADER (1903-1990) A German chemist who accidentally developed the toxic nerve agents viz., sarin, tabun, soman, cyclosarin while attempting to develop new insecticides. Schrader & his team, thus, introduced a new class of synthetic insecticides, the organophosphorous insecticides & defined the structural requirements for insecticidal activity of anticholinesterase compounds. He is also called the “Father of the nerve agents”
  58. 58. K. K. CHEN (1934) • Demonstrated antagonist effect of sodium nitrite & sodium thiosulphate in cyanide poisoning.
  59. 59. R. A. PETERS, L. A. STOCKEN, & R. H. S. THOMPSON. (1945) • Developed dimercaprol as an antidote to arsenic containing war gases {lewisite}.
  60. 60. THALIDOMIDE DISASTER 1959-1960’s  was first marketed in 1957 in West Germany under the trade-name Contergan.  The German drug company Chemie Grünenthal (now Grünenthal) developed and sold the drug.  Primarily prescribed as a sedative or hypnotic, thalidomide also claimed to cure “anxiety, insomnia, gastritis, and tension".  Afterwards, it was used against nausea and to alleviate morning sickness in pregnant women.  Thalidomide became an over the counter drug in Germany on October 1, 1957.  Shortly after the drug was sold in Germany, between 5,000 and 7,000 infants were born with phocomelia (malformation of the limbs).  Only 40% of these children survived.  Throughout the world, about 10,000 cases were reported of infants with phocomelia due to thalidomide.
  61. 61. RACHEL CARSON (1962) • Started crusade against the use of DDT & published the great book “silent spring”.
  62. 62. LOUIS J. CASARETT & JOHN DOULL (1971) • published the 1st modern Toxicology textbook titled “Toxicology: The basic science of poisons”.
  63. 63. NUCLEAR ACCIDENTS AT THREE MILE ISLAND NEAR HARRISBURG, PENNSYLVANIA. (1979) • The accident began with failures in the non-nuclear secondary system, followed by a stuck-open pilot-operated relief valve in the primary system, which allowed large amounts of nuclear reactor coolant to escape. • The partial meltdown resulted in the release of unknown amounts of radioactive gases and radioactive iodine into the environment.
  64. 64. BHOPAL GAS DISASTER, (1984)  occurred due to accidental release of methyl isocyanate killing thousands & injuring hundred’s of people.
  65. 65. CHERNOBYL NUCLEAR POWER PLANT ACCIDENT (1986) Occurred in Soviet Union spreading radioactive debris over several countries.
  66. 66. LATTER HALF OF THE 20TH CENTURY A noteworthy achievements led to better understandings of the ecology of poisons & venoms. Some answers have been discovered to such puzzling questions as: 1. Why are plants & animals poisonous/venomous ? 2. What have poisons contributed to evolution ? 3. How can an understanding of poisons & venoms contribute to the management of both free-ranging wild animal populations & domestic animals ?
  67. 67. COEVOLUTION?? Plants & herbivorous animals (insects) coevolved in an adversarial relationship. Plant population developed various strategies for coping with herbivores that could potentially destroy them! Mechanical means  thorns, spines, harsh outer coats of stems/leaves. Chemical deterrents  PSM’s bitter tasting, offensively odorous, poisonous or have antinutitional effects. As plants became more efficient in producing PSM’s  animals, likewise improved their own methods of coping.
  68. 68. The case of coevolution of plants & insects is easily demonstrated, while evidence for plant/mammal coevolution is more elusive. Seems logical ?? 1) Insects & plants have shared the earth for approximately 250 million years (Carboniferous Period, Paleozoic Era). 2) Primitive mammals have been on earth only for 100 million years (Cretaceous Period, Mesozoic Era).
  69. 69. The progenitors of large, wild herbivorous animals viz., cattle/horse/bison/antelope didn’t appear until 40 million years ago. All domestic animals arose from their wild counterparts less than 12,000 years ago!!!
  70. 70. Even though mammalian herbivores may not have coevolved with plants like insects, there is sound evidence that plant (dietary) selection is determined by the presence & quantity of PSM’s in the part of the plant consumed viz., leaves, stem, fruit & seeds.
  71. 71. ANIMAL TOXIN ECOLOGY Animal toxin & venoms are used to obtain • Food • Deter predation • Regulate population • Aid in exploiting a territory • Aid in defense against enemies. Just as in plants, the end products of sec. metabolites are channeled to storage sites within or upon the animals body, where there is slow turnover. The slow turnover minimizes the necessity of excessive expenditure of precious energy & chemical resources to this function.
  72. 72. CONCLUSIONS Poisons & venoms have served a vital role in the evolution of plants & animals. • The pharmacological effects of plants & animals = PSM (Plants Secondary Metabolites). • The determining factor of whether a substance is a medicine or a poison may be a matter of dosage. Scientists are just beginning to unravel many of the mysteries of plant/animal/animal interactions.
  73. 73. DISCUSSIONS
  74. 74. REFERENCES. Murray E. Fowler: Veterinary Zootoxicology. (CRC press). Sandhu H. S. & Brar R. S: Text Book of Veterinary Toxicology. Garg S. K: Veterinary Toxicology. Matham V. K: Essentials of Toxicology. Wikipedia & Google images.

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