Mining and other extractive industries are likely to feature heavily in Kenya’s plans to diversify its economy. Gold, gems, titanium, fluorspar, limestone and other minerals have the potential to add billions of shillings to exports, create jobs and generate public revenue. But poorly regulated mining can come with serious occupational and community health risks.

Health implications

Gold mining exposes workers and surrounding communities to mercury, arsenic, silica dust and, where used, cyanide. Acute mercury exposure can cause respiratory and gastrointestinal symptoms, neurological disturbance and kidney injury, while chronic exposure can cause tremors, cognitive and neurological impairment and kidney damage, with particular risks to foetal and childhood brain development.

Cyanide poisoning can rapidly cause headache, confusion, breathing difficulty, seizures, cardiovascular collapse and death. Chronic arsenic exposure is associated with skin lesions, cardiovascular disease and increased risks of skin, lung and bladder cancers. Drilling and crushing gold-bearing rock can additionally expose workers to crystalline silica, causing silicosis and increasing the risks of tuberculosis, chronic lung disease and lung cancer.

Gemstone mining, including tsavorite, ruby and tourmaline extraction in Taita-Taveta, primarily presents dust and physical hazards. Acute risks include eye and airway irritation, fractures, crush injuries, head injuries and death from collapsing or poorly supported shafts. Repeated inhalation of silica-containing rock dust can cause irreversible silicosis, chronic obstructive pulmonary disease and lung cancer and substantially increases susceptibility to tuberculosis.

Titanium mineral-sands mining, including ilmenite, rutile and zircon, exposes workers to mineral dust, noise, heavy machinery and processing-related hazards. Acute effects include respiratory and eye irritation, hearing injury and industrial trauma. Long-term inhalation of mineral dust can contribute to chronic respiratory disease, while zircon-bearing mineral sands can contain naturally occurring radioactive materials, making appropriate radiation monitoring important for workers with sustained occupational exposure.

Limestone, silica, gypsum and quarry-stone extraction generate substantial quantities of airborne dust during drilling, blasting, crushing and transportation. Acute exposure can cause coughing and irritation of the eyes and respiratory tract, alongside serious injuries from blasting, falling rock and machinery. Chronic crystalline-silica exposure can cause silicosis, chronic obstructive pulmonary disease and lung cancer. The risk of tuberculosis increases.

Impact assessment

Fluorspar mining exposes workers to fluoride-containing dust as well as the general hazards of drilling, blasting and mineral processing. Acute exposure to high concentrations of fluoride-containing dust can irritate the eyes and respiratory tract, while prolonged excessive fluoride exposure can affect bones and teeth, including skeletal fluorosis. Mine waste and contaminated water can extend exposure to surrounding communities.

Soda ash and salt extraction expose workers to highly alkaline or saline dust and aerosols. Acute exposure can irritate the eyes, skin and respiratory tract, while repeated occupational exposure may contribute to persistent respiratory and dermatological problems. Diatomite extraction creates significant dust exposure; where the processed material contains crystalline silica, prolonged inhalation can cause silicosis and increase the risks of chronic respiratory disease and lung cancer.

Manganese and other metallic-mineral extraction introduces additional toxic-metal risks. Acute high-level manganese exposure can affect the respiratory and nervous systems, while prolonged occupational exposure can produce neurological impairment known as manganism, characterised by movement, behavioural and cognitive abnormalities. As Kenya expands exploration of copper, nickel, chromite, rare-earth elements, niobium and other critical minerals, the specific toxicological risks of the ore, processing chemicals, mine waste and associated metals must be assessed before commercial extraction begins.

Mining projects should begin with a clear assessment of occupational exposure, environmental contamination and community health risks. These assessments should not be treated as administrative requirements that are completed once before a licence is issued.

Kenya’s legal and regulatory framework already requires environmental and social impact assessment for major mining activities. Mining licences also come with obligations relating to environmental protection, community development and worker safety.

Health agencies’ role

The problem is that communities often have limited access to the information generated through these processes. For every major mining operation, communities should be able to access information on what minerals are being extracted, the chemicals used in processing, environmental monitoring results, occupational injury data, water quality findings and mitigation measures.

The ministries responsible for Health, Labour, Mining, Water and Environment should not operate in isolation. Mining-related health risks cut across all these sectors. Kenya would benefit from a national mining and health surveillance system. Such a system could track occupational injuries, respiratory disease, heavy-metal exposure, water contamination, maternal and child health effects and other health outcomes in mining regions.

Economic activity and public health are not competing objectives. But without transparent monitoring and effective enforcement, the health costs of mining can be transferred to workers and communities while the economic benefits accrue elsewhere.

For gold-mining communities, this should include testing for mercury and arsenic exposure where scientifically indicated, routine monitoring of drinking water and safer alternatives to mercury-based gold processing. For quarry workers and miners exposed to dust, occupational health programmes should include respiratory screening, tuberculosis surveillance, access to appropriate personal protective equipment and enforcement of dust-control standards.

The most important point is that mining policy cannot be evaluated only in terms of export revenue, royalties or employment. It must also be evaluated against measurable health indicators. If Kenya intends to expand extractive industries as part of its economic strategy, then occupational health, environmental health surveillance and community health protection must be treated as core infrastructure of the sector.

Economic activity and public health are not competing objectives. But without transparent monitoring and effective enforcement, the health costs of mining can be transferred to workers and communities while the economic benefits accrue elsewhere.

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Dr Bosire is a medical doctor and lawyer. stebosi51@gmail.com