Classification of edible vegetables affected by different traffic intensities using potential curves

Heavy metals in soils have largely been used to evaluate the impact of motorised traffic in the vicinity of motorways. Also in this field of work it is of paramount importance to analyse the vegetables grown in these areas since their consumption is one of the main sources of metal intake by people; not in vain human food is directly or indirectly derived from plants. Accordingly, a set of edible vegetable samples were first analysed and, then, classified employing different multivariate chemometric techniques; among them, SIMCA and a simplified mode of potential curves. The analytical variables were selected after a comprehensive study of roadside soil pollution where Pb, Cd and Cu were found to be the main metallic pollution tracers. Different groups of vegetables were obtained which were explained as a function of both the agricultural conditions (private versus commercial) and the different traffic intensities supported by the cultivated areas. (C) 1999 Elsevier Science B.V. All rights reserved.