Everyday Applications of Toxicology

Is the food I eat safe What about the air I breathe and the water I drink Is it as bad as the media says Should I worry, and if so, when These questions arise often in this age of high chemical use. We use more chemicals on our crops than ever before. As more countries become industrialized, air pollution becomes a pressing issue. We continue to lose wetlands as we require more land for more people. How will this impact our water supply  

In the sixteenth century, Paracelsus said, All things cu e poison and nothing [is] without poison. Solely the dose determines that a thing is not a poison. This holds true today. A dose is defined as the amount of a chemical entering the body, and is a function of the amount of exposure to that chemical. Sometimes we are exposed to a small amount and get extremely ill (e.g., food poisoning), while at other times we are exposed to a lot and don t notice a thing (salt). 

Paracelsus quotation is key to understanding what toxicity mccms. Knowing that a chemical is toxic does not automatically imply that adverse effects will result from exposure to any amount. Most of us Ccm tolerate recisonable amounts of table salt without fear of adverse effects. However, ingesting too much Scdt Ccm cause heart toxicity, or disrupt the water bcdcmce in our cells, blood, and kidneys. Toxicity can be defined as the degree to which a chemical inherently causes adverse effects. 

For an understanding of the relative danger associated with a chemical, inherent toxicity must be linked to some level of exposure. We have developed a relative toxicity scale for chemicals, depending on the amount of a chemical necessary to cause adverse effects. This scale is shown in Table 2.1, along with examples for 

Moderately Toxic Slightly Toxic Practically Nontoxic Relatively Harmless 

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The discussion of lead and risk assessment focuses on how a basic understanding of toxicology has applications in everyday life. The purpose of this book is to provide... 

This chapter is not intended to present an overview of all recent developments in toxicology, but through the use of examples attempts to illustrate the breadth and variety of toxicology research and applications that touch our everyday lives. 

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