ACCESS: Innovatives approaches to understand complex microbial communities for ecoengineering the degradation of herbicides in stresseed agricultural soils

MERINI, LJ

Rio de Janeiro - Brasil

Conferencia; 2nd Mercosur Congress on Chemical Engineering ? 4th Mercosur Congress on Process System Engineering ? EMPROMER 2005.; 2005

2,4-D (2,4-Dichlorophenoxyacetic acid) is a hormone-like herbicide widely used in agriculture. Although its half life in soil is approximately 1 to 2 weeks, the amounts introduced in the environment are such that sometimes the herbicide or its metabolites reach surface or underground water courses. It represents a serious risk for human health and the environment, due to the toxic properties of this compound and some of its degradation products. For the assessment and monitoring of 2,4-D amounts in polluted soils, it is important to accurately measure the amount of 2,4-D and its metabolites. There is evidence that 2,4-D extraction from soil samples depends seriously on the physical and chemical properties of the soil. The issue of this work is to assess the multiple variables that influence the recovery and subsequent analysis of 2,4-D and the main metabolites from soil. The results obtained show that recovery efficiency is affected mainly by: the solvent and method used for the extraction, the amount and solvent used for dissolving the herbicide and the soil water content at the moment of spiking. An optimized protocol for the extraction and quantification of 2,4-D and its main metabolite from soil samples is presented.