PARENT SESSION
19 - Pesticide Ecotoxicology
8:00 AM to 6:30 PM, Monday, 13 May 2002
Exhibition Area

(19-02) Dynamics of organochlorine pesticides (OCPs) during the vegetation period of tomato (Lycopersicum esculentum) growing under outdoor conditions.

Gonzalez, Mariana^*,1, Miglioranza, Karina^1,2, Aizpún de Moreno, Julia¹, Moreno, Victor¹, ¹ Department of Marine Science, Mar del Plata University. Funes 3350, Mar del Plata, Argentina, Argentina² CONICET

ABSTRACT- Levels of OCPs in tomato growing under outdoor conditions and devoid of direct OCPs applications during a whole vegetation period were determined. The plants were taken at two different time periods (October-March), together with soil remained physically attached to the roots. Leaves, stems, roots and fruits were analyzed separately. OCPs were quantified by GC-ECD with a Shimadzu 17-A chromatograph. During the first period (without fruit) the plants were grown in an enriched soil (fallen leaves) and total OCPs concentatration was 4X-fold higher than in soils from the second period (with fruit). Concomitantly roots from the first period showed the highest total OCPs values (21, 6 ng/g. ww). HCHs (-, -, - y - isomers) and DDTs were the main OCPs groups found among all tissues from each period. Moreover, high values of chlordanes (- and -isomers), and heptachlor and aldrin with metabolites were also accumulated in roots from the first period. Endosulfan was the main OCP found in fruit-peel (8,2 ng/g.ww) and leaves (1,1 ng/g.ww) from the second period, which is expected given that this pesticide has a peak usage during the summer months. The root bioconcentration factors varied among periods being in the second one higher for the most OCPs analyzed, maybe due to the previous OCPs uptake from enriched soil before transplanting. The DDT/DDE ratio > 1 and the -/- HCH ratio <1 would indicated that both DDT and -HCH (Lindane) are still in use. In spite of most of these pesticides are forbidden they were found in a non-target area as aresult of long-range atmospheric transport and deposition.

Key words: organochlorine pesticides, tomato, vegetation period, bioconcentration factors