Sea shells clean up toxic water

Scientists working in Vietnam have discovered a method of removing toxic metals from water using sea shells.

Heavy metals such as cadmium, zinc, lead, and iron dissolved in water can be removed by pouring the water over a bed of crushed clam or mussel shells, found researchers from Austra’s Graz University of Technology.

The shells, made from a form of calcium carbonate, readily swap their calcium atoms in exchange for heavy metal atoms.

Heavy metals are locked into the shells in solid form, whilst the calcium released is absorbed by the water.

The technique could prove a vital life-saving resource to many people in the majority world who currently lack access to clean drinking water.