EVALUATION OF SOME HEAVY METALS CONCENTRATIONS IN SOME VEGETABLES IN KADUNA METROPOLIS

Abstract

This study assessed the levels of heavy metals concentration present in waterleaf (Talinum triangulare) and lettuce from three various farms in an outskirt of Sabon Tarshi within Kaduna metropolis, Kaduna State using Atomic Spectrophotometer. Six (6) samples of waterleaf and lettuce were obtained from 3 farms in the outskirt of Sabon Tarsha. The farms were located closed to industrial areas. Standard method was followed for sample treatment, digestion, and analysis of selected heavy metals: lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni) and cobalt (Co), iron (Fe), strontium (Sr), copper (Cu), zinc (Zn) and mercury (Hg).The results showed that in waterleaf and lettuce from the three farms, concentration (mg/kg) of heavy metals were: Pb (0.32-18.80), (0.47 -0.85) Cd (0.25-0.57), (0.87-2.61) Cr (0.00-2.16), (0.13-0.57) Ni (4.81-8.30), (0.70-6.30) Co (3.90-6.01), (0.09-0.52), Fe (112.3119.57), (0.09-0.46), Sr (55.20-82.22), (9.35-22.14), Cu (1.83-5.51), (0.58-1.05), Zn (0.02-0.43), (7.88-29.10), Hg (0.00-0.01), (0.00-0.0019). Heavy metals were higher in waterleaf than in lettuce except for Zn. It may be concluded that there is high tendency of exposure to heavy metals by those who consume waterleaf and lettuce in the studied locations since the levels in waterleaf and lettuce from all farms studied generally exceeded the FAO/WHO limits.