The Smithsonian’s Museum Conservation Institute (MCI), working with an extensive network of Smithsonian collaborators, has addressed pesticide detection and quantification, assessment of health risk, and strategies for mitigating that risk. Pesticides were applied historically to Smithsonian collections to eradicate and/or prevent infestation by insects, rodents, and mold. Many of these chemicals are now known to be hazardous to human health. MCI visiting scientist and fellow, Odile Madden, developed protocols for calibrating and using portable X-ray fluorescence instruments to detect heavy metal pesticide residues — arsenic, lead, and mercury — on ethnographic collections. Currently, she is developing methods to trap and detect volatile organic pesticide residues using Raman spectroscopy. The protocols and results have been reported in a number of high-profile invited presentations and publications. The goal of the collaborative project, with the National Museum of the American Indian and the National Museum of Natural History, is to identify potentially hazardous pesticide residues on collections and, ultimately, to accurately communicate whether or not the risk posed is significant.