Modern society is very dependent upon numerous chemical substances. Chemicals have a wide variety of uses, including drugs to prolong our lives and pesticides to control insect and weed pests. Life would be drastically different without the availability of these chemical substances but, while the benefits of chemicals should be appreciated, the hazards they present to our health and to the health of the environment should also be taken into account. Most chemicals are safe when manufactured, transported, and used properly, but when they are mishandled or misused, they can threaten both the health of humans and the health of wildlife. In this book, some common chemicals used in society and the conditions under which some of these chemicals are dangerous are reviewed. The benefits of these chemicals, some problems they can cause, and how their harmful effects can be reduced or avoided are also discussed. (CW)