Environmental implications of illegal heavy metal mining in the Shalten area, Egypt’s Eastern Desert

Abstract

ABSTRACT Most of Africa’s illegal mining operations are conducted in rural areas, but along the Red Sea coast, they primarily occur in the Eastern Desert, where they are regarded as the major source of revenue. Soil samples were collected and examined at an illegal gold mining site in the far south of Egypt’s Eastern Desert to determine the toxicity levels of eight heavy metals for pollution load index (PLI), Igeo, and health (Au, Ag, As, Hg, Ni, Cr, Zn, and Pb). The methodology used in this study was categorized into fieldwork with restricted rules within the visit, soil samples collected from the field, chemical analyses for heavy metals, and statistical analyses by applying six equations to define the environmental status of the study area. It was found that the PLI increases contamination as an environmental risk grade, Igeo, reaches grade 6, which is highly contaminated, and the average hazard index (HI) for the individual elements is high (>0.01). The health risk assessment results for Ni and Cr showed that oral intake was the main mode of exposure to heavy metals in the tailings of illegal mines. In addition, the average levels of As, Hg, Cr, Ni, Pb, and Zn were higher than the equivalent background levels for soils. Thus, adult cancer risk (CR) exceeds the permissible level of 10−4. The illicit mining activities in the Eastern Desert also resulted in heavy metal contamination with substantial noncarcinogenic hazards for As and Zn, necessitating urgent remediation.