Toxicology“The science of poisons”

Catalina Marambio JonesMajor lesson 3, May 30th

Toxicology research

• Paracelsus (1493-1541) "All things are poison, and nothing is

without poison; only the dose permits something not to be poisonous.“

• Orfila (1787-1853), father of the toxicology

Death of Socrates, painted by Jacques Louis David (1787)

Hemlock (Conium maculatum)

• coniine• 100 mg can be fatal• 6-8 fresh leaves or

even less amount of seeds and roots

"The Death of Cleopatra," painted in 1892 by Reginald Arthur

Egyptian cobra (Naja haje)

• Injects 175-300 mg of venom in one bite.

• Stops nerve signals• Respiratory failure

in 10 min.

The Borgias in the italian Renaissance

“The Cantarella poison”

• Arsenic, copper, and phosphorus.

• Cantharidin• Blistering agent and

chemical burns.• As little as 10 mg is

potentially fatal.

TCDD poisoning

Chemical and biological warfareWorld war I

World war II, Approximately 4 million people were murderer in gas chambers.

Iran-Iraq war Genocide against the Kurdish people,

approximately 5000 people were killed.

Toxicology in the news

Accidental poisoning in the news

"Toxicology is the study of the adverse physicochemical effects of chemical, physical or biological agents on living organisms and the ecosystem, including the prevention and

amelioration of such adverse effects."

Risk assessment

Reference: www.riskbites.com

First: what is the potential to cause harm ?

Reference: www.riskbites.com

Second: are we in contact with the hazard? , how much?

Reference: www.riskbites.com

Third: Connecting hazard and exposure

Reference: www.riskbites.com

Fourth: Calculating the risk

Reference: www.riskbites.com

Hazard

Hazard but no exposure

Reference: http://25.media.tumblr.com/tumblr_lxiq2rz8el1qkzk87o1_500.jpg

Hazard and exposure

Reference: http://www.freakingnews.com/pictures/62000/Shark-Attacks-Sleeping-Surfer--62036.jpg

Dose response curve

Dose

Resp

onse

Dose response curve

100%

50%

0%20 40 60 80 100 110 120 140 160 180 200

Threshold

Dose ( for example mg/Kg)

Resp

onse

Dose response curve

100%

50%

0%20 40 60 80 100 110 120 140 160 180 200

LD50 or ED50 Threshold

Dose ( for example mg/Kg)

Resp

onse

(fo

r exa

mpl

e m

orta

lity)

How much is too much? -Dose response

A bit of shark…….

• A bit more………

How much is too much? -Dose response

• Now you are playing with your luck….

How much is too much? -Dose response

Going over the threshold……

How much is too much? -Dose response

Finally a response!!!!

How much is too much? -Dose response

Reference: www.sharkmans-world.eu

Think-pair share

1. What is more toxic?

Think-pair share2. What is the therapeutic index?

100%

50%

0%20 40 60 80 100 110 120 140 160 180 200

Dose (mg/Kg)

Mortality

Anti-inflammatory

Popu

latio

n sh

owin

g t

he re

spon

se (%

)

Experimental part

Record: concentration and number of shrimp alive after exposure.

Questions?

See you tomorrow!