October 10, 2015 — Filter-feeding bivalve molluscs, such as mussels, oysters, scallops and clams, are a useful and tasty source of protein. They can, though, also be harbingers of illness. A filter-feeder lives, as the name suggests, by trapping and consuming particles (mostly bacteria and single-celled algae) suspended in water it pumps through its body. If those particles are themselves toxic, they can seriously discomfort, and occasionally kill, a human who eats a mollusc that has been feeding on them.

The most common culprits are algae called dinoflagellates and diatoms, several species of which make potent toxins. These algae often multiply into spectacular blooms along coastlines. Even in the absence of such a bloom, though, they can be abundant enough to cause problems. For this reason, in most places in the rich world at least, bivalves intended for sale have to be tested before they go to market. That involves taking samples to a laboratory, which is cumbersome and time-consuming. What is needed is a simple test that can be carried out on-board a ship. And Waqass Jawaid, of Queen’s University in Belfast, thinks he has one.

One way of screening shellfish is pretty crude. This is to inject a mouse with a sample and see if it gets ill— a procedure no longer used in Europe, but still permitted in parts of America. The alternative, a mix of chromatography and mass spectrometry, is more sensitive, but requires expensive equipment and trained staff. Dr Jawaid’s method, which he and his colleagues report in the Journal of Agricultural and Food Chemistry, employs antibodies to create a system similar to a pregnancy test.

Read the full story at The Economist