Abstract: A method of operating a screening system includes applying an electromagnetic field to a specimen in a region at least partially enclosed by electromagnetic shielding and measuring an output from a sensor, wherein the output is induced by an interaction of the electromagnetic field and the specimen. The method also includes dislodging trace particles from the specimen within the region, collecting the trace particles, and identifying the trace particles. The method further includes evaluating an association of the specimen with a substance based on the measured sensor output and the identified trace particles.