Concentrations and Health Risk Assessment of Potentially Toxic Elements in Medicinal Herbs from Northern Nigeria


  • Mohammad Bashir Sulaiman aDepartment of Pure and Industrial Chemistry, University of Nigeria, Nsukka, Enugu State, Nigeria
  • Aishatu Santuraki Department of Chemical Sciences, Federal University Kashere, Gombe State, Nigeria
  • Auwal Adamu Department of Pharmaceutical and Medicinal Chemistry, Gombe State University, Gombe State, Nigeria
  • Uzoamaka Ezenobid Department of Chemistry, Michael Okpara University of Agriculture, Umudike, Nigeria
  • Abdullahi Gimba Department of Science Laboratory Technology, Gombe State Polytechnic, Bajoga, Gombe State, Nigeria
  • Oluyinka Akinlotan Department of Chemistry, Kogi State College of Education (Technical) Kabba, Kogi State, Nigeria



assessment, concentration, potentially toxic elements, health risk, medicinal herbs


The concentrations of potentially toxic elements (Fe, Cd, Pb, Cu, Ni, Cr, and Zn) in most consumed medicinal herbs in Northern Nigeria were analyzed using Atomic Absorption Spectrometry (AAS). Twenty medicinal herbs were selected and purchased from the local markets. The findings of the study revealed that the investigated herb samples contained considerable levels of elements; Cu, Fe, Pb, Cd, and Cr above the permissible limits. The health risk observed as hazard index (HI) indicated that values were >1, in some samples. Therefore, the consumption of these studied medicinal herbs should be monitored to prevent the health implication due to a high level of these elements in the medicinal herbs.

Author Biography

Mohammad Bashir Sulaiman, aDepartment of Pure and Industrial Chemistry, University of Nigeria, Nsukka, Enugu State, Nigeria

Pure and Industrial Chemistry


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