The Impact of Pesticides - Academy Publish

Dynamic and Batch Adsorption Studies of Isoproturon onActivated CarbonJosé Luis Sotelo, Juan García, Araceli Rodríguez, Silvia ÁlvarezABSTRACTThe presence of endocrine disruptors as pesticides in water sources is becoming aconcern in drinking water production, wastewater treatment, and water reuseapplications due to potentially adverse health effects associated with thesecompounds. Numerous experimental studies with animals have shown that a numberof pesticides are involved in endocrine disruption, while many of the well knownherbicides (such as isoproturon) or insecticides are blamed for long term toxicityand carcinogenicity.In this sense, isotherm experimental runs are performed in batch system to estimatethe type of isotherm and their parameters under different operation conditions. Theeffect of chemical composition and structure of isoproturon were investigated.Adsorption isotherms seemed generally approach to the Freundlich isotherm modelwith an excellent fit to experimental data.In a second part, experimental breakthrough curves of isoproturon are assessed infixed-bed columns. Several experiments were conducted using aqueous syntheticsolutions under different initial concentrations, flow rates and bed weights ofadsorbent. Different parameters of the column, such as adsorption capacities atbreakthrough time and saturation time, length of the mass transfer zone (MTZ),fractional bed utilization and removal percentage have been calculated. Severaldynamic adsorption models were applied obtaining a good fit to experimental data.The theoretical breakthrough curve has been obtained.INTRODUCTIONThe potential presence of pharmaceuticals, pesticides, personal care products(PPCPs) and other endocrine disrupting chemicals (EDCs) in the wastewater is anemerging concern among the public, and thus an appropriate consideration for aplanned indirect potable water reuse project. These compounds have been detectedin a wide variety of environmental water samples including sewage flows, surfaceand groundwater, with concentrations generally ranging from traces to ppb levels.The lack of validate of analytical methods, non-uniform monitoring data, and thelack of definite information about the fate and effects of these compounds and/ortheir metabolites and transformation by-products in the aquatic environment makesaccurate risk assessments problematic (Stackelberg et al., 2004; Youbin et al.,2010).AcademyPublish.org - The Impact of Pesticides339