Artisanal Mining in Nigeria Exposes Communities to Dangerous Levels of Airborne Lead
A groundbreaking study released recently has shed light on the alarming levels of airborne lead exposure resulting from artisanal lead mining in Nigeria. For the first time, researchers documented that self-employed artisanal lead miners are generating airborne lead levels that exceed the United States’ Permissible Exposure Limit by a factor of ten, underscoring an urgent public health crisis in mining communities throughout Zamfara State. These findings highlight the overlooked but significant contribution of informal mining activities to environmental contamination and toxic exposure among both workers and nearby residents.
The investigation also extended to artisanal gold ore processing operations in Northern Nigeria, revealing that airborne lead concentrations can surpass allowable exposure limits by more than thirty times. Gold extraction in these communities involves numerous manual and mechanical grinding techniques aimed at liberating gold from ore, but these methods inadvertently aerosolize lead and other toxic metals present in the mineral matrix. This exposure pathway poses heightened risks not only to the miners but also to people living in proximity to processing sites, who may be subjected to chronic inhalation of lead-laden dust particles.
Published in the Journal of Occupational and Environmental Hygiene, the study offers critical insight into the magnitude of toxic airborne exposures inherent in artisanal mining and mineral processing sectors. Drawing from observational data gathered within Zamfara State, it revealed that underground lead miners experience airborne lead levels up to 22 times higher than occupational safety standards permit. This dramatic elevation directly correlates with widespread childhood lead poisoning documented in the region, shedding light on the mechanisms by which environmental contamination translates into severe public health outcomes among vulnerable populations.
Lead ore extraction remains primarily driven by the global demand for lead-acid batteries, which continue to dominate energy storage markets despite rapid growth in lithium-ion and alternative battery technologies. These batteries play a pivotal role in supporting renewable energy infrastructure, especially in rural and off-grid areas reliant on solar and wind power systems. However, the environmental and occupational hazards tied to acquiring and processing lead ores present a paradox: the pursuit of clean energy solutions is inadvertently perpetuating toxic exposures in mining communities.
Manti Michael Nota, the study’s lead author and a lecturer at Ardhi University in Dar es Salaam, Tanzania, emphasized the severity of these exposures, stating that “lead concentrations among underground miners reached levels 22 times above the occupational air standard, significantly contributing to elevated rates of child lead poisoning." His remarks underscore the dire need for more stringent controls and protective measures within the informal mining sector, where regulatory oversight is often lacking, and industrial hygiene practices are minimal or nonexistent.
Beyond mining, the manufacturing and recycling of lead batteries pose additional hazard points for lead exposure. These processes have historically been linked to occupational health crises, including cases of severe lead poisoning among workers and surrounding communities. Industrial recycling operations often operate without adequate environmental safeguards, facilitating the dissemination of lead dust and fumes into residential areas and affecting the neurological development and cardiovascular health of exposed populations.
Perry Gottesfeld, Executive Director of Occupational Knowledge International (OK International), the NGO that collaborated with Doctors Without Borders/Médecins Sans Frontières (MSF) on this study, highlighted the global relevance of these revelations. “Artisanal lead mining remains one of the most hazardous informal economic activities worldwide, yet it receives disproportionately little attention given its profound health impacts. Our research demonstrates that communities engaged in self-employed lead mining face extraordinary contamination risks from airborne metals,” he stated, calling for increased international focus on occupational safety in this sector.
Data show that the majority of lead ore mined in Nigeria is exported to China for refinement, a trade that has surged by over 360% between 2013 and 2022. This dramatic expansion not only spotlights Nigeria’s growing role in the global lead supply chain but also raises concerns regarding transboundary transportation of toxic materials and associated risks along the export routes. As demand for lead continues to escalate, informal mining activities are simultaneously expanding in many developing countries, exacerbating environmental degradation and public health emergencies.
The challenges of informal lead mining are not confined to Nigeria. In Kabwe, Zambia, decades of unregulated lead extraction have resulted in severe widespread poisoning and environmental pollution. Similarly, Southern Myanmar has witnessed a surge in artisanal lead mining since early 2021, following political upheaval, with products destined for Chinese processing centers. These parallel situations underscore a global pattern whereby informal mineral extraction exacerbates environmental health disparities, particularly in low- and middle-income nations.
The study authors caution that lead’s toxicity is multifaceted, causing severe neurological damage and mortality particularly among children inhabiting mining regions. Even chronic low-level inhalation exposures contribute to approximately five million annual deaths worldwide, largely attributable to cardiovascular disease. Investment in safer mining technologies and rigorous exposure mitigation strategies would yield substantial health and economic benefits by avoiding costly treatments and long-term disability associated with lead poisoning.
Despite the dire consequences, efforts by the Nigerian government to ban lead mining in Zamfara State have had limited success. Persistent lead toxicity cases continue to emerge, indicating ongoing mining activities that evade enforcement. Approximately 40 million small-scale, informal miners operate in over 70 countries globally, many engaged in artisanal gold and lead extraction, representing a significant but underrecognized component of the worldwide supply for these metals.
Given the documented health risks and environmental contamination linked to artisanal lead mining, the research team urges immediate attention from public health authorities, governments, and international organizations. Interventions aiming to formalize mining practices, provide education, and promote safer extraction and processing methodologies are critical to safeguarding communities from the devastating consequences of lead exposure. Enhanced surveillance, regulatory frameworks, and community involvement stand as essential pillars for mitigating this growing global occupational health challenge.
Subject of Research: People
Article Title: Airborne lead exposures during artisanal lead mining and gold ore processing in Zamfara, Nigeria
News Publication Date: 9-May-2025
Web References: 10.1080/15459624.2025.2491490
Image Credits: Occupational Knowledge International
Keywords: Environmental health, Human health, Pollution
