Determination of ‘Acceptable’ and ‘Safe’ Levels for Human Exposure to Chemicals

Abstract

An important and yet perhaps controversial issue that comes up in attempts to establish ‘safe’ or ‘tolerable’ levels for human exposure to chemical constituents relates to the notion of an ‘acceptable chemical exposure level’ (ACEL). The ACEL may be considered as the concentration of a chemical in a particular medium or product that, when exceeded, presents significant risk of adverse impact to potential receptors. In fact, in a number of situations, the ACEL concept tends to drive the public health risk management decision made about several consumer products. However, the ACELs may not always result in ‘safe’ or ‘tolerable’ risk levels per se—in part due to the nature of the critical exposure scenarios, receptor-specific factors, and other conditions that are specific to the particular hazard situation. Under such circumstances, and insofar as possible, it becomes necessary to develop more stringent and health-protective levels that will meet the ‘safe’ or ‘tolerable’ risk level criteria.