ABSTRACT
Chemicals, whether natural or anthropogenic, present hazards to humans. Properly stored, handled, and used, chemicals present minimal hazards, but rarely, if ever, can the risk be said to be zero. The probability of an undesirable exposure occurring is something greater than zero. In exposure assessment, we cannot speak in absolute terms such as always or never. Fallible environmental engineers and industrial hygienists hope, at best, to reduce the risk of an undesirable exposure to something approaching zero. The whole premise of this book is that, for whatever reason, the hazards of chemical exposure are not minimized, and, therefore, we need to find out exactly what hazards exist, so someone may take the exposure information we give them and make a policy decision about making the workplace, or outside environment, safer. If the decision belongs to a higher authority, the exposure assessment is taken one step further by analyzing the probability of any specific person, or community, being harmed, and the entire project becomes a risk assessment. For our purposes, we will stop with the exposure assessment proper. We will discuss risk assessment along the way, with respect to exposures. Before learning to predict exposures, then, let’s examine the specific hazards of chemical exposure to humans.
