Chemistry Reference
In-Depth Information
Part
1
Basic Principles
The irst part of the topic will deal with the basic principles that determine the envi-
ronmental distribution and toxic effects of organic pollutants in order to set the stage
for Part 2, which describes the properties and behavior of major groups of com-
pounds that fall into this category. The first chapter puts this issue into evolutionary
perspective. From a toxicological point of view, organisms have been exposed to
toxic xenobiotics for much of the evolutionary history of this planet—much longer
than they have encountered human-made organic pollutants, which are the main
subject of this topic. Indeed, many such compounds have functioned as chemical
weapons of both defense and attack, and animals have been found to possess detoxi-
cation systems for them, which also work against products of the chemical industry
to which they could have had no previous exposure. Also, natural products with
“biological activity” have often been used as models in the development of new
pesticides and drugs.
Following this introduction, the next three chapters will describe the principles
and processes that determine the fate and behavior of organic pollutants in the natu-
ral environment. Throughout, emphasis will be given to the importance of the physi-
cal, chemical, and biological properties of the compounds themselves in determining
their fate and behavior. Chapter 2 is concerned with the factors that determine the
distribution and toxicity of these compounds in individual organisms. Chapter 3 will
describe the factors that determine the distribution of chemicals through the major
compartments of the gross environment and attempts to develop descriptive and pre-
dictive models for this. Chapter 4 will focus on distribution and effects in communi-
ties and ecosystems.
