Water-purifying ozone column. Column containing ozone beads that destroy organic pollutants. The column will treat any waste water or industrial effluent passed through it. Each of the 2 millimetre-diameter silica beads has ozone, a highly reactive form of oxygen, adsorbed on its surface. This technique is ten times more potent than pumping ozone through waste water, where only 10 per cent of the ozone dissolves and attacks the pollution. As the ozone is used up, the bright blue beads fade in colour. A white appearance means that they must be recharged with ozone. This process was developed by a team from Bradford University, England, headed by Chedly Tizaoui.