Different types of safety questions come to mind when we consider that millions of people are exposed to commercially available products day after day, year after year—sometimes for an entire lifetime! For instance, will a product cause serious harm if accidentally swallowed or splashed into a child's eye? Can it cause skin or respiratory aller gies? Is a new material or product likely to produce harmful effects such as liver damage, birth defects, or cancer, when used over a long period of time? These are just some of the questions that must be considered before any new product is marketed. Product safety is rarely a simple yes or no answer. Back in the 16th century the scientist Paracelsus phrased this well when he observed, "All substances are poisons. The right dose differentiates a poison and a remedy." Virtually every known chemical has the potential to cause injury or death if present in a sufficient amount or used in an inappropriate way—even table salt or water can be harmful! This means scientists must consider many factors to deter mine the overall degree of risk or safety associated with a material's use under various conditions. Factors such as: with how much of the material will people come into contact? In what ways—will the product be applied to skin, eyes, taken by mouth, injected, or inhaled? How long and how often will a person be exposed to the material? The answers to these questions may be quite different for workers exposed to large amounts of individual ingredients versus a consumer using the final product. Each factor can dramatically change the way a living system will respond to the same material. Today, scientists use a variety of research methods including non animal systems, laboratory animal tests, and clinical studies with human volunteers to gain the knowledge needed to make safety judgments. This process involves far more than a simple "cookbook" approach! Getting information about the potential human exposure and ways in which people will use and possibly misuse a product helps determine the right safety questions to ask. Each new product then undergoes a custom-designed evaluation that involves testing only in those areas that are appropriate. If the necessary information is already available, then additional testing is not conducted. (next page)
						Q What are alternatives to animal testing? A Computer banks of existing information, computer models, cell or tissue cultures, chemical and physical tests, and human clinical studies are used in product safety research to help reduce the need for animals.