Scientists are working on a detection test which they say could be a quick way of spotting dangerous contamination of food or water.

Since September 11, many experts have warned of the threat of terrorist attack with highly-destructive pathogens such as smallpox or anthrax.

A team of researchers from Clemson University in South Carolina, US, is working on a nano-scale test which should not only provide an instant verdict, but also be easy even for the public to use.