1. The Risks and Benefits of Chemicals By: Gabriel Smith and David Jones

2. Sanitation Sanitation involves all of the methods used for removal, treatment, and disposal of wastes. Waste water treatment is one area of sanitation. It's goal is to make water safe for use by people and other organisms. For Example: Much of the drinking water in the United States is treated to remove contaminates.

3. Food Preservatives For centuries, humans have predicted methods to control the growth of microorganisms that spoil food. Chemicals used to prevent food spoilage caused bu microorganisms are called food preservatives. Salt and vinegar may have been the first chemicals used as preservatives. Both chemicals inhabit the growth of microorganisms that can spoil food.