Virgin olive oil is one of the essential products for the economy of Mediterranean countries. The possible residues of pesticides that can reach the oil may be a risk to public health, thus causing the prohibition of its marketing by the health authorities. This paper is a preliminary study on photochemical degradation of pesticide residues using a small-scale prototype (1 L capacity). The method presents an effective alternative for the complete photodegradation or reduction of these chemicals using ultraviolet light without harming the quality parameters of the virgin olive oil. The photodegradation yields have varied within the range 7-80% depending on the time and temperature applied. (C) 2009 Elsevier B.V. All rights reserved.