|
Getting your Trinity Audio player ready...
|
When scientists peel back a handful of soil from a farming field or test a spoonful of stew at a market stall, they are doing more than measuring elements in the ground or on a plate.
They are reading the invisible ledger of decades of activity, where water flowed, what was burned, and what was dumped. The new studies in Ghana have opened one such ledger and found, in places, numbers that demand attention: mercury, arsenic, lead, and cadmium at concentrations that, at least locally, are high enough to threaten health and food security.
This explainer breaks down what the tests measured, how worried people should be, who made the statements, and the concrete steps experts and authorities are recommending.
What was tested, and who did the testing
Two complementary efforts lie behind the headlines.
• A field assessment led by Pure Earth Ghana in collaboration with Ghana’s Environmental Protection Authority (EPA) and funded by the UK Foreign, Commonwealth & Development Office (FCDO). Teams sampled soil, water, air (mercury vapour), crops, and fish across Artisanal and Small-scale Gold Mining (ASGM) sites in several regions between August 2024 and September 2025. The stated aim: map hotspots and pathways of heavy-metal contamination in people’s environment and food systems.
• A national screening by the Food and Drugs Authority (FDA) with UNICEF support on parts of the work that sampled commonly consumed foods and some household/cosmetic products from markets across the country to look for elevated levels of toxic metals.
Both projects are described by their authors and partners as preliminary and evidence-building, targeting sampling to identify hotspots and guide follow-up, rather than issuing sweeping nationwide verdicts.
The headline numbers (what shocked scientists)
The studies flagged a string of alarming local measurements, high enough to exceed accepted safety thresholds by large margins in the places sampled:
- Soil: In Konongo (Ashanti), mercury levels were recorded at approximately 56 ppm — roughly 560% above the 10 ppm threshold cited in the report — and arsenic readings in some locations reached 10,060 ppm in isolated samples.
- Water: In Konongo Odumase, arsenic was measured at 3.30 mg/L — hundreds of times the usual drinking-water limits. Other sites have shown unsafe lead levels in the water.
- Air: During smelting in Wassa Kayianko, teams measured mercury vapour peaks (reported at about 150 µg/m³) — concentrations hazardous to anyone living or working very near open amalgam burning.
- Food: Vegetables such as pumpkin leaves and kontomire, and fish from places like Akwaboso, were found to have elevated lead, arsenic, and cadmium levels. The FDA’s screening also raised alarm about some cereal mixes commonly used as infant complementary foods (locally sold “Tom Brown” mixes were among the product groups cited).
A crucial caveat: these are spot samples taken to locate and characterise contamination. They highlight hotspots and exposure pathways rather than claiming that every tomato, every fish, or every packaged cereal in Ghana is contaminated.
Why those numbers matter: the health basics
Mercury, arsenic, lead, and cadmium are not benign. They bioaccumulate, meaning they build up in organisms and move up the food chain, and many cause irreversible damage even at low chronic exposures:
- Lead damages developing brains; childhood exposure is associated with reduced IQ, behavioural problems, and lifelong learning deficits.
- Methylmercury (the form that concentrates in fish) causes neurological harm, particularly in unborn children and infants.
- Arsenic and cadmium affect the kidney and are linked to cancers and chronic disease over time.
Public-health bodies such as the World Health Organisation list these metals among global chemical hazards. Vulnerable groups — pregnant women, infants, and young children — are the most at risk.
What researchers told DUBAWA
The voice of the field was blunt. Roderick Daddey-Adjei, Deputy Chief Executive (Food Division), FDA, told DUBAWA, “We should be very, very concerned… those limits [observed] are more than 50 times, 100 times above those limits… the point I’m gravitating to is that we have reached a point where we have not been careful… some of these things have found their way into the food chain.”
On her part, Blessing Gbadago, Project Manager, for Pure Earth Ghana, offered context and caution, “This is more or less the findings or the first stage of this research where we uncovered that there was levels of mercury that’s localised exposure in some of the food samples… these are common staples in Ghanaian homes… this is not also to cause panic and fear but then this is something that is going to enable us to design solutions.”
Hobson Agyapong, Principal Programme Officer, EPA, stressed the evidence-building purpose and the path ahead, “We thought it wise… to back it with evidence. This is a preliminary research… to alert us as to the way forward as a nation… the next thing that we need to do is to look at how best we can then remediate those sites and then restore it for even agricultural purposes.”
Those quotes underline two simultaneous messages from the authorities: the numbers are worrying where they occur, and the immediate priority is targeted action rather than alarmism.
So, should consumers panic?
No. But neither should they be complacent.
• Don’t panic: The research identifies hotspots and certain contaminated items. It does not assert that all food in Ghana is unsafe. Branded, regulated products that are routinely tested are generally lower risk than unregulated, unlabelled market mixes whose origin cannot be traced.
• Be cautious: Where possible, pregnant women and parents of infants can favour tested, branded products and municipal water supplies or bottled water that meet regulatory standards. Avoid sourcing food (or drinking water) from known artisanal-mining processing sites or rivers known to be impacted by mining runoff.
What scientists, regulators, and public-health experts want next
The studies do not stop at the measurements; they point to concrete next steps:
Immediate
- Rapid public-risk communication to affected communities (clear, factual advice to avoid unnecessary panic).
- Quick access to safe drinking water in places where arsenic or lead exceed limits.
Short term
- Biomonitoring: test people (blood, urine, hair) in identified hotspots to measure exposure and determine whether clinical follow-up or treatment is needed. The Pure Earth assessment explicitly lists biomonitoring as the next phase.
- Intensive market surveillance and testing, especially of unbranded, loose mixes and products that feed infants and children.
Medium and long term
- Remediation of contaminated soils and water includes options such as engineered clean-ups, containment, and phytoremediation, where appropriate.
- Safer mining practices: reduce mercury use in artisanal mining, control open amalgam burning, and implement water-management measures so contaminated runoff does not reach farms.
- Traceability in food supply chains enables produce to be traced back to the farm, allowing for targeted recalls and safer procurement by markets and institutions.
Conclusion
The studies are an important early warning, not a blanket condemnation. Where numbers are high, the threat is real and calls for rapid public health and environmental action: biomonitoring, access to safe water, focused remediation, and a programme to make artisanal mining safer. For journalists and citizens, the immediate task is to insist on transparency: publish the methods, release the datasets, and commit to the follow-up that turns warnings into protection.
