TOXICOLOGY PART III

Toxins

Toxin

a biologically produced poison Although there are some man-made toxins

Made either for defense or for predation Examples

Hemotoxins – target and destroy red blood cells Necrotoxins – cause cell death (necrosis) Neurotoxins – affect nervous system of animals Cytotoxins – individual cell reactions

Toxicity

Determined by… Dosage The chemical or physical form of the

substance How it enters the body The body weight and physiological

conditions of the victim, including age and sex

Toxicity cont’d

The time period of exposure Chronic exposure – larger amounts over time Acute toxicity – dose large enough to cause

immediate problems Whether other chemicals are present in the

body or in the dose Synergism – combined effects of substances

that exceeds the sum of their individual effects Antagonism – combined effect of substances

that decrease their individual effects

LD50

Amount of a substance that kills half the test population

Allows for comparison of toxicity of substance

Regulatory Organizations

Food and Drug Administration (FDA) Pharmaceuticals, food additives, medical devices

Environmental Protection Agency (EPA) Agricultural and industrial chemicals released into the

environment Consumer Product Safety Commission

Toxins in consumer products Department of Transportation (DOT)

Shipment of toxic chemicals Occupational Safety and Health Administration

(OSHA) Exposure to chemicals in the workplace

Toxins – Venoms - Poisons

Hemlock Arsenic Lead Anthrax Cholera Botulinum Diphtheria Ricin VX Nerve Gas Agent Orange Strychnine Sarin

Cases of Assassinations and Murder Socrates Napoleon Viktor Yushchenko Albert Magnus Georgi Ivanov Markov Alexander Litvinenko – Polonium-210

Biological Warfare

Historical Bioterrorism Events