So-called "dirty bombs
" are designed to spread significant amounts of radioactive dust and debris throughout a populated area.
But working out what kind of radiation dose the local people have received is a difficult business, not least because this may involve testing tens or hundreds of thousands of them.
That is a problem because current techniques for estimating radiation dosage rely on blood samples that can only be taken by trained individuals. This severely limits the rate at which people can be tested. The tests look for changes in the metabolites generated by cells when they are exposed to radiation and which then end up in the blood.
However, Albert Fornace
at Georgetown University in Washington, DC, US, funded by the US government, says that these metabolites also turn up in saliva and urine, but not in high enough concentrations for current testing equipment to detect.
However, Fornace and his team say the required sensitivity is possible using a new generation of lab-on-a-chip technologies that he is developing. Because they rely on easily obtainable saliva and urine samples, the machines should allow a much higher throughput of tests in an emergency.