Studies on the levels of some heavy metals in vegetables grown in three irrigation zones of Katsina state, Nigeria

Abstract

Levels of Cd, Cr, Cu, Fe and Pb in some vegetables irrigated in three irrigation zones of Katsina State have been studied using Atomic Absorption Spectrometry. Results revealed that Cd was not detected in any of the samples analysed while other metals were present at varying levels. Fe and Pb were found to be present in all the samples with levels above WHO/FAO recommended MPL for the metals. Highest values were obtained in Kofar Marusa irrigation area. It was thus concluded that the high levels of the metals in that area was due the fact that sewage water containing a lot of heavy metal contaminants was used for the irrigation. It was further concluded that the consumption of vegetables irrigated in that area may pose health threats to the consumers. Thus, it was recommended among others, that ban should be imposed on the use of sewage water for irrigation purpose.