Removal of pesticides by use of ozone or hydrogen peroxide ozone

This article deals with the efficiency of an ozonation step in drinking water treatment plants remove pesticides. These tests are carried out with a laboratory technique, the ''OZOTEST'' method, which simulates operating conditions on site and allows a complete oxidation assessment. Efficiency of the two oxidant systems - ozone and ozone coupled with hydrogen peroxide - is evaluated for 11 pesticides commonly analyzed in control laboratories. Comparison of the two systems is made in terms of pesticide removal, but also in terms of ozone consumption. Matrix effects and contact time are also taken into account, and an order of reactivity for each system considered is suggested.