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Bio 408 Environmental Toxicology

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					Lecture 2: History of Toxicology
          History of Toxicology
Toxicology is arguably the oldest scientific discipline, as the
  earliest humans had to recognize which plants were safe
  to eat.




Most exposure of humans to chemicals is via naturally
  occurring compounds consumed from food plants.
Humans are exposed to chemicals both inadvertently and
  deliberately.
        Occupational and
    Environmental Toxicology
            Environmental toxicants (air
             and water pollutants) are
             substances harmful to the
             environment and to humans.
Environmental toxic substances are both natural and
  man made.

Public perception that man-made ones are more
   serious than natural ones - Reality: both
   are serious.
5,000,000 yearly deaths worldwide due
to bacterial toxins (Salmonella, E. coli)
       Occupational and
   Environmental Toxicology
Many examples of diseases associated with
 specific occupations were recorded in
 antiquity, but they were not considered
 serious because the health of the workers
 was not a societal concern.
                    History
2700 B.C. - Chinese journals: plant and
            fish poisons



                           1900-1200 B.C. Egyptian
                           documents that had directions for
                           collection, preparation, and
  administration of more than 800 medicinal and poisonous
  recipes.
800 B.C. - India - Hindu medicine includes
  notes on poisons and antidotes.
50-100 A.D. - Greek physicians classified over
  600 plant, animal, and mineral poisons.
                        Cleopatra 69-30 BC
Cleopatra – Queen of Egypt (69-30 BCE)


                                         Queen of Egypt -
                                           Experimented with
                                           strychnine and other poisons
                                           on prisoners and poor.
                                           Committed suicide with
                                           Egyptian Asp (Egyptian
top
                                           cobra sometimes used in
                                           executions).
Hippocrates 460-377 BC
          Hippocrates was a Greek physician
          born in 460 BC on the island of Cos,
          Greece. He became known as the
          founder or father of modern medicine
          and was regarded as the greatest
          physician of his time .A person of
          many talents he named cancer using
          the Greek word karkinos (crab)
          because of the creeping, clutching
          crab-claw appearance of cancerous
          tissue spreading into other tissue
          areas. He moved medicine toward
          science and away from superstition.
          He was also noted for the hippocratic
          oath, a code of ethics practiced by

          physicians that is still used today.
                  History
50- 400 A.D. - Romans used poisons for
           executions and assassinations.

         The philosopher, Socrates, was executed
           using hemlock for teaching radical
           ideas to youths.

Avicenna (A.D. 980-1036) Islamic authority on
   poisons and antidotes.

1200 A.D. - Spanish rabbi Maimonides writes
  first-aid book for poisonings,
   Poisons and Their Antidotes
       History
Swiss physician Paracelsus (1493-1541)
   credited with being
“the father of modern toxicology.”

“All substances are poisons: there is none
    which is not a poison. The right dose
    differentiates a poison from a remedy.”

Illuminated the dose-response relationship
   The Black Death (1347-1351)
• Striking first in 1347 in
  Western Europe with
  similar accounts in
  the middle east and
  Asia, the Black Death
  was a devastating
  Plague that wiped out
  1/3 to ½ of the world’s
  population
• Caused by a bacterial
  toxin (Yersinia
  pestis) carried by
  fleas
                       History

                   Italian physician
               Ramazzini (1713) published
                 “De Morbis Artificum”
                 (Diseases of Workers)
describing "asthma" in bakers, miners, farmers, gilders,
tinsmiths, glass-workers, tanners, millers, grain-sifters,
stonecutters, ragmen, runners, riders, porters, and
professors. Ramazzini outlined health hazards of the dusts,
fumes, or gases that such workers inhaled. The bakers and
horse riders described by Ramazzini would today probably
be diagnosed as suffering from allergen-induced asthma.
The lung diseases suffered by most of the other workers
would now be classified as "pneumoconiosis," a group of
dust-related chronic diseases.
    Occupational and
Environmental Toxicology
    - Paracelsus - Miner’s Disease (1533) came from
          inhaling metal vapors. Pioneered the use of
         chemicals and minerals in medicine

 - Hill (1761) linked tobacco (snuff)
          to cancer.


  - Pott (1775) linked scrotal cancer
         and soot (benzo(a)pyrene) in
         chimney sweeps.
                  19th Century
• Spanish physician Orfila
  (1815) established
  toxicology as a distinct
  scientific discipline.
• Evaluated the effects of
  toxins on different organ
  systems.
• Wrote Trait des poisons
  (1813), which described
  in great detail various
  types of poisons and their
  bodily effects
         20th Century History
20th Century – cell and molecular age
  Paul Ehrlich –developed staining procedures to
  observe cell and tissues and pioneered the
  understanding of how toxicants influence living
  organisms. Known for his work in hematology,
  immunology, and chemotherapy.
          Occupational and
      Environmental Toxicology
- Radium dial painters,
  “aniline dye” workers (1900)
  painters licked their brushes
  to pull it to a point.

- Shoe salesmen (1950s)
  shoe-fitting fluoroscopes:
  radiation of feet in shoes
  of children and repeated
  exposure for salesmen.
         Occupational and
      Environmental Toxicology
Industrial chemical workers
(1940-present)
• Workers typically are exposed to
  a greater number of carcinogens
  for longer periods of time.
• Occupations with high risk of cancer :
  Health care workers, pharmaceutical and
  laboratory workers, refinery workers, rubber
  workers, furniture makers, and pesticide workers.
Mr. Yuk - 1971


               Symbol adopted
          by the Pittsburgh Poison
          Center at The Children’s
          Hospital in 1971. Used to
           educate children and
         parents about poisons and
            to prevent accidental
                 poisonings
                 History
20th Century
Rachel Carson – In 1962, she alarmed
The public about dangers of pesticides in the
  environment.
http://www.youtube.com/watch?v=T_Njv5Ygg0g&f
  eature=related
          Silent Spring I


“As crude a weapon as a cave man’s
club, the chemical barrage has been
hurled against the fabric of life.”

Rachel Carson – Silent Spring (1962)
          Silent Spring II


“The “control of nature” is a phrase
conceived in arrogance, born of the
Neanderthal age of biology and the
convenience of man.”

Rachel Carson – Silent Spring (1962)
                  Ecotoxicology


• The term "ecotoxicology" was coined by Truhaut
  in 1969, who defined it as "the branch of
  Toxicology concerned with the study of toxic
  effects, caused by natural or synthetic pollutants,
  to the constituents of ecosystems, animal
  (including human), vegetable and microbial, in
  an integral context” (Truhaut, 1977).

                              Wikepedia, 2007
              Tipping Point
• Many rivers were
  choked with garbage
  and sewage
• Cuyahoga River in
  Ohio actually caught
  on fire
• Marked decline in
  several animal
  populations
                 References
• Chapman, P. M. 2002, "Integrating toxicology
  and ecology: putting the "eco" into
  ecotoxicology", Marine Pollution Bulletin, vol. 44,
  no. 1, pp. 7-15.
• Larry Johnson, 2007. Partnership for
  Environmental Education and Rural health
  (PEER). Lecture given to the Society of
  Toxicology
• Gilbert, Steven G. A Small Dose of Toxicology:
  The Health Effects of Common Chemicals.
               Review Questions
1.   When was cancer discovered and by whom? What else is this
     individual known for?
2.   What were the contributions of Paracelsus to toxicology?
3.   At what period in history was occupational diseases first
     recognized as a societal problem?
4.   Name and describe 3 occupational diseases which acutely
     affected workers.
5.   What significant event lead to the onset of the study of ecological
     effects resulting from environmental contaminants?
6.   How have our concerns concerning exposure to toxic substances
     changed throughout history?
7.   Construct a historical timeline including dates which illustrates the
     history of toxicology.

				
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