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MAY 2005
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Video: Fatal Attraction
Video: Deadly Delicacy
Audio: Botox & Piano
Online Extra: Toxic Tale 13
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Learn More
In Learn More the National Geographic magazine team shares some of its best sources and other information to expand your knowledge of our featured subjects. Special thanks to the Research Division.

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 Did You Know?  
 Related Links  
 NGS Resources  

Did You Know?Did You Know?

Why is it that a certain food, plant, or chemical could make your pet cat sick but not harm you at all? Selective toxicity. This is when a chemical harms one kind of living being without harming another form of life, even though the two may co-exist. This biological diversity makes it difficult for toxicologists to predict the toxic effects of a chemical in one species (humans) based on experiments performed on another species (lab animals). However, by taking advantage of the biological diversity, it is possible to create agents such as pesticides and insecticides that are lethal for one species and harmless to another. 
Even similar species can respond to a chemical in much different ways.  For example, if you give the same chemical to a mouse, a rat, a hamster, and a guinea pig, each may have a completely different response. One could die, one be somewhat sick, another be very sick, and the last one could be perfectly fine.
There can be varying responses to chemicals even within the same species due to subtle genetic differences. Take caffeine, for instance. Some people get very jittery from the smallest amount of caffeine, but others can drink several shots of espresso just before going to bed and sleep peacefully throughout the night.
These differences are what first attracted Dr. Mike Gallo, a toxicologist and associate director  at the Cancer Institute of New Jersey, to the study of toxicology. According to Gallo, "Toxicology gives you the chance to understand biology."
—Marisa Larson

Related Links

ASPCA Animal Poison Control Center
Worried that your pet got into something it shouldn't have? The ASPCA Animal Poison Control Center can help with any poison-related emergency and help teach you how to prevent such emergencies.

Environmental Protection Agency
Protecting human health and the environment is the EPA's directive. Since 1970 this governmental department has been working toward a cleaner, healthier environment. Its website contains information about many household and environmental contaminants you should know about and avoid.

National Capital Poison Center
Nearly all poison exposures occur in the home from such common items as medicines, cleaning supplies, and cosmetics. The National Capital Poison Center gives information on what to do in an emergency poisoning situation and also instructs people on how to avoid such poisonings.

International Spy Museum
Visit a museum solely dedicated to espionage and find out more about their collection of international spy-related artifacts, some of which were photographed for this story.


Chou, Wen-Chien, and others.   "Role of NADPH oxidase in arsenic-induced reactive oxygen species formation and cytotoxicity in myeloid leukemia cells." Proceedings of the National Academies of Science, vol. 101 (March 2004).
Available online at

Farrell, Michael. Poisons and Poisoners: An Encyclopedia of Homicidal Poisonings. Bantam Books, 1992.

Klaassen, Curtis. Casarett & Doull's Toxicology: The Basic Science of Poisons. McGraw-Hill, 1996.

Mayor, Adrienne. Greek Fire, Poison Arrows, and Scorpion Bombs: Biological and Chemical Warfare in the Ancient World. Overlook Duckworth, 2003.

Thompson, C. J. S. Poisons and Poisoners. Barnes & Noble Books, 1993.

NGS Resources

Hogan, Dan, and Michelle Hogan. "Freaky Frogs." National Geographic Explorer (March/April 2004), 10-15.

Cahill, Tim. "Into Bad Air! The CO2 Chronicles." National Geographic Adventure (November 2003), 54-62, 101-6.

Mitchell, John G. "Our Polluted Runoff: Widespread as Rain and Deadly as Poison." National Geographic (February 1996), 106-25.

Moffett, Mark. "Poison-Dart Frogs: Lurid and Lethal." National Geographic (May 1995), 98-111.

 Murawski, Darlyne A. "A Taste for Poison: Passion Vine Butterflies." National Geographic (December 1993), 122-37.
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