Quality close to water plantain (Musa Aab) in south lake, Zulia State

Abstract

The Southern Region of the Lake in the state of Zulia presents a mostly agricultural land use with predominance of banana cultivation. A variety of fertilizers and pesticides are used to increase the productivity of the crop, which causes serious environmental pollution when these are deposited in the soil and are washed into the rivers. Because of this problem, it was proposed to evaluate the quality of water sources affected by the banana crop. For this purpose, three water sample collection
points were selected during the month of October 2011; these were transported to the Product Control Laboratory of INIA-Zulia for their physicochemical analysis and determination of pesticides by chromatography. Toxicity bioassays were performed where neonates of the cladocerum Moina sp. were used to determine the mean lethal concentration (LC50). The physicochemical parameters of the waters studied are within the normal limits established in the Offi cial Gazette (Decree 886). Pesticide  analysis detected the presence of the insecticide methamidophos, although its concentration was lower than the maximum permissible limit (0.2 ppm). The (LC50) of the water samples is 88.04 % (Probit analysis), which is equivalent to 1.13 units of toxicity (UT) which classifi es it as slightly toxic water. The results of the bioassays revealed the presence of toxic compounds that were not detected
by conventional analytical methods.