Total antioxidant responses of edible plants to high DDTs levels: Use in phytoremediation strategies.

MITTON, FRANCESCA; GONZALEZ MARIANA; SHIMABUKURO VALERIA; MONSERRAT JOSE M; MIGLIORANZA KARINA SILVIA BEATRIZ

Portland USA

Congreso; 31th Annual Meeting of Society of Environmental Toxicology and Chemistry (SETAC) North America; 2010

Persistent Organic Pollutants (POPs) are of environmental concern due to their recalcitrance in soils and sediments, global distribution, and toxicity. Phytoremediation is a promising in situ technology involving the plantassisted removal of soil contaminants. It uses the inherent physiological abilities of plants to decrease pollutants in soil by mechanisms operating within the rizhosphere or by contaminant uptake into the plant. However, some pollutants are known to enhance Reactive Oxygen Species (ROS) formation in different organisms and this can result in differences about the efficiency of phytoremediation. Organisms protect themselves from such harmful effects with a number of both enzymatic and non-enzymatic defences that constitute a complex antioxidant defence system. Since the antioxidant systems can act in a cooperative way, determination of total antioxidant capacity provides a better understanding of organism responses to ROS-induced toxicity. This study aimed to compare the total antioxidant responses of different edible plant species grown in contaminated soil with high DDT (500 ppb) and endosulfan (5 ppb) levels from Patagonia Argentina under greenhouse experiments. Plants of soybeans, sunflower and alfalfa were harvested after 15 days of exposure. Leaves and roots were sub-sampled for analytical determination of pesticides and total antioxidant capacity against peroxyl radicals (ACAP) measurement. Results showed that roots presented higher ACAP related to leaves. Moreover, differences among species were also observed. Alfalfa leaves presented the highest pesticide content (DDTs) and ACAP levels followed by soybean and sunflower. The knowledge about levels of pesticide in different organs and the biochemical responses related to those contaminants is necessary for planning phytoremediation strategies and future risk assessment.