Sensors small enough to mix in with paint or coatings of different types, could be applied to every container carrying cargo. The sensors could not only monitor for explosives, biological agents and illegal narcotics, but could also track the shipment. Presently there are systems available, which will track shipments, however they are limited to tracking the vehicle and not the goods themselves. Sensors impregnated into the packaging of the goods, or perhaps attached to the goods themselves, would allow for the position of the goods, to be monitored on a continuous basis.
Sensors placed in the cabs of trucks will detect the use of alcohol or illegal narcotics and send a signal directly to the shipper, or simply not allow the driver to start the engine. Think of the many road accidents caused by drivers falling asleep at the wheel or driving under the influence. Sensors in the cabs would reduce these incidents and again many lives could be saved.
School Buses and Public Transport could also carry these sensors, ensuring the drivers are fit to be behind the wheel, and that nothing harmful can happen to our children and the public.