Pesticide mitigation in museum collections

The Smithsonian Museum Conservation Institute Workshop on Pesticide Mitigation was one of the first professional meetings dedicated to current research on removing pesticide residues from museum objects. Seven papers were presented at the workshop, and two more were added to introduce topics not focused on during the meeting but of significant importance when considering actual application of any of these methods. The aim of the workshop was to bring together conservators, scientists, and even industry representatives to discuss the complex issues associated with pesticide removal from artifacts and to provide representative examples of the research and work being carried out at different institutions in the United States and abroad. Among the issues explored were possible methods and techniques that might become useful in the museum conservation field to reduce, mitigate, clean, or remediate undesirable pesticides on objects.^ The meeting also served to inform conservators and scientists in the Smithsonian Institution of the wide range of approaches that are currently being tested and that might prove useful in the future. Topics covered in the presented papers included removal of mercury and arsenic contamination with α-lipoic acid; the treatment of Haudenosaunee medicine masks with surface active displacement solutions; the possibility of using mercury-resistant bacterial communities to remediate contamination; solvent extraction through the use of special solvents such as hydrofluoroethers; carbon dioxide as a cleaning fluid either in liquid or in supercritical state; and novel cleaning techniques either through the use of additives to improve the efficiency of liquid or supercritical CO2 cleaning, other gases in a supercritical state, or other techniques such as fluidized beds.^ The introduction of novel techniques at the workshop was encouraged in order to broaden the range of promising methods that might improve the technology of pesticide mitigation or remediation. The two supplemental papers discuss pesticide analysis on objects and safety measures that should be implemented by institutions with contaminated collections.