ABSTRACT

The method of calculating an acceptable concentration depends on whether a toxicant has a threshold or nonthreshold dose-response relationship. If the toxicant has a nonthreshold dose-response relationship, acceptable concentrations can be calculated for the general population and workers on the basis of acceptable excess lifetime risk or acceptable number of excess cases generated per year. If the toxicant has a threshold dose-response relationship, acceptable concentration can be calculated for the general population or workers on the basis of a NOEL or NOAEL. There are several important concepts associated with the calculation and evaluation of an acceptable concentration.