PT11 Exposure to POPs Through Terrestrial Vegetation
Exhibit Hall
8:00 AM - Tuesday
(PT142) Measurement of Chiral Pesticides in Vegetables Grown Organically, Traditionally and in a Controlled Environment.
Motley, Tanieka1, Falconer, Renee1, 1 Chatham College, Pittsburgh, PA, USA
ABSTRACT- In recent years, there has been increased demand for organic foods. Producers of organic foods often employ alternative techniques such as hand-weeding or introduction of a pest predator for control instead of using man-made chemical pesticides. Organically grown foods are thought to be a healthy choice because of low or no pesticide levels. This study looked at the differences in pesticide levels in two root vegetables, potatoes and carrots. The organic and traditionally grown vegetables were purchased from local groceries while control plants were grown in a pesticide-free greenhouse on site. The skin and flesh of all samples were analyzed separately to try to determine the location of the pesticides. Pesticides/metabolites analyzed included DDT, chlordane, oxychlordane, heptachlor, heptachlor epoxide, dieldrin and hexachlorocyclohexane. In general, controlled environment carrots and potatoes had the lowest pesticide concentrations, followed by organically grown carrots and potatoes. Traditionally grown samples had the greatest pesticide concentrations even though most of these pesticides have been banned in the U.S. for years. Enantiomeric analysis of chiral pesticides was done for samples with detectable levels. Non-racemic signatures of chiral pesticides suggest enantiospecific breakdown occurred, although whether this occurred in the plants or prior to uptake is not known.
Key words: pesticides, organochlorines, chiral, vegetables