Unknown risk: co-exposure to lead and other heavy metals among children living in small-scale mining communities in Zamfara State, Nigeria

Int J Environ Health Res. 2014 Aug;24(4):304-19. doi: 10.1080/09603123.2013.835028. Epub 2013 Sep 17.


The lead poisoning crisis in Zamfara State, Northern Nigeria has been called the worst such case in modern history and it presents unique challenges for risk assessment and management of co-exposure to multiple heavy metals. More than 400 children have died in Zamfara as a result of ongoing lead intoxication since early in 2010. A review of the common toxic endpoints of the major heavy metals advances analysis of co-exposures and their common pathologies. Environmental contamination in Bagega village, examined by X-ray fluorescence of soils, includes lead, mercury, cadmium, arsenic and manganese. Co-exposure risk is explored by scoring common toxic endpoints and hazard indices to calculate a common pathology hazard risk ranking of Pb > As > Hg >> Cd > Mn. Zamfara presents an extreme picture of both lead and multiple heavy metal mortality and morbidity, but similar situations have become increasingly prevalent worldwide.

Keywords: Nigeria; exposure; heavy metals; lead poisoning; risk.

Publication types

  • Review

MeSH terms

  • Child
  • Environmental Exposure / adverse effects*
  • Environmental Exposure / analysis
  • Environmental Monitoring
  • Heavy Metal Poisoning, Nervous System / etiology
  • Heavy Metal Poisoning, Nervous System / prevention & control
  • Humans
  • Lead / analysis
  • Lead / toxicity
  • Lead Poisoning, Nervous System, Childhood / etiology*
  • Lead Poisoning, Nervous System, Childhood / prevention & control
  • Metals, Heavy / analysis
  • Metals, Heavy / toxicity*
  • Mining*
  • Nigeria
  • Risk Assessment
  • Risk Management
  • Soil Pollutants / analysis
  • Soil Pollutants / toxicity*


  • Metals, Heavy
  • Soil Pollutants
  • Lead