Approaches to understanding chemosensory responses: new directions and new caveats

This article describes recent research on sensory irritants that should prove helpful to setting occupational exposure limits (OELs) for this class of chemicals. In addition, background information is provided to assist in recognizing the relevance and importance of this type of work. Research conducted by Dr. Steven Youngentob and others addresses the recovery of olfactory function following exposure to high concentrations of sensory irritants. Their research has combined several different experimental methods to gain insight on how olfactory receptor neurons (ORNs) are replaced. Other important work relevant to setting OELs has been conducted by Professor Gerd Kobal, who has relied on human brain imaging during chemosensory stimulation. Commentary on these two approaches is followed by suggestions on how to address the relative lack of detailed normative information on human responses to odors and irritants.