GHANA · HEALTH AND MINING
Key Facts
- —The country Ghana is a West African country of about 34 million people and Africa’s largest gold producer, where illegal small-scale gold mining is called galamsey.
- —What happened A review of 45 studies appeared online on 26 September; Graphic Online reported its findings on 21 October.
- —The scale The review covered 11 mining districts, five metals (lead, cadmium, chromium, mercury, arsenic) and four crops: tomato, pepper, garden egg and onion.
- —The worst sites At the most polluted single sites, arsenic reached 200 times and mercury 400 times the Codex limit, mostly in the Ashanti and Western Regions.
- —The health score A combined hazard index, which adds up the risk from all metals, topped 1.0 in every mining community where it could be worked out.
- —Who did it Eric Osei Bonsu of the CSIR-Crops Research Institute in Kumasi led the team, which published in the journal Environmental Monitoring and Assessment.
- —Still open The press reports do not name the 11 districts, and they quote no Ghanaian health or farm agency.
Galamsey vegetables, meaning crops grown near illegal gold mines in Ghana, carry toxic metals, a review of 45 studies shows. Graphic Online reported the findings on Wednesday 21 October.
Galamsey is the Ghanaian word for illegal gold mining, and the metals found include lead, arsenic, cadmium and mercury. For US readers, the finding matters because Ghana’s small-scale gold sector, which earns billions of US dollars, also fouls farmland.
What the Review Looked At
The team read 45 peer-reviewed studies published between January 2020 and January 2025, drawn from 11 mining districts across Ghana. They tracked five metals into four everyday crops: tomato, pepper, garden egg (a small African aubergine) and onion.
Eric Osei Bonsu of the CSIR-Crops Research Institute in Kumasi led the work with co-authors Michael Kwabena Osei, Harry Okyere and James Korang. The CSIR is the Council for Scientific and Industrial Research, Ghana’s state research body, and the paper is in Environmental Monitoring and Assessment.
Cadmium Moves Easily Into Vegetables
Cadmium, a metal linked to kidney damage, moved from soil into galamsey vegetables more readily than the other four metals. In tomato and garden egg its transfer factor, the ratio of metal in the plant to metal in the soil, was above 1.0.
A figure above 1.0 means the vegetable can hold as much cadmium as the soil beneath it, or more. The authors note that this describes a concentration pattern and does not by itself prove the plant actively draws the metal in.
Where the Worst Readings Came From
Lead, arsenic and mercury exceeded limits set by Codex Alimentarius, the food-standards body of the UN’s food agency and the World Health Organization. The worst results for galamsey vegetables came from the Ashanti and Western Regions, two gold-mining areas.
At the single most polluted sites, arsenic reached up to 200 times the limit and mercury up to 400 times. Data from the Eastern and Central Regions were thinner, so the picture there is less complete.
What the Combined Health Score Means
The reviewers also used the hazard index, which adds up how much of each metal a person eats against a daily amount regarded as safe. In every mining community where they could work it out, the score was above 1.0, signalling a raised risk of non-cancer illness.
Chromium moved little into plants, with a transfer factor below 0.50, even where soil held more than 300 milligrams per kilogram. The authors warn that this is not proof of safety, because almost no study separated harmless chromium from its far more toxic hexavalent form.
What the Researchers Recommend
The authors call for targeted testing of vegetables, soil and irrigation water in mining districts rather than thin checks spread across the whole country. They also want buffer zones between mines and farms drawn from local contamination data instead of one fixed distance.
Washing galamsey vegetables and handling them carefully after harvest can remove dirt from the surface, but not metals already taken up inside the plant. Bonsu said galamsey is usually discussed in terms of rivers and forests, and the review adds food to that list.
What It Means for US Readers
Ghana’s small-scale miners exported US$11.6 billion of gold this year, as the Rio Times reported on Ghana’s small-scale gold exports. The review shows a human cost beside that trade, and it adds to the damage described in Ghana’s polluted rivers.
The study covers galamsey vegetables grown for Ghanaian tables and does not say that any reached export shelves. Investors and aid donors in health, water and farming can still read it as a sign of the clean-up bill and the regulatory pressure ahead.
What Is Not Known
Press reports of the study do not list the 11 districts, and the reviewed data end in January 2025, so current levels may differ. Neither Graphic Online nor GhanaWeb quoted any Ghanaian health, food or environmental agency in their reports.
The authors call for long-term tests on people, to link contaminated food to metal levels in the body. Until then, nobody can say how many Ghanaians have fallen ill from eating galamsey vegetables.
More: Ghana news in English, every day from The Rio Times.
Frequently Asked Questions
What is galamsey?
Galamsey is the Ghanaian name for illegal small-scale gold mining, often done with mercury in rivers and on farmland. The worst readings in this review came from the Ashanti and Western Regions.
Which toxic metals were found in the vegetables?
The review covered lead, cadmium, chromium, mercury and arsenic. Lead, arsenic and mercury went above Codex limits at several sites, and cadmium moved most readily from soil into tomato and garden egg.
Are all Ghanaian vegetables unsafe?
No, the review points to farms near mining sites, not to the whole country. The worst readings came from single sites in the Ashanti and Western Regions.
Does washing remove the metals?
Washing removes dirt and surface contamination. It cannot remove metals that the plant has already taken up into its edible parts.
Who carried out the review?
Eric Osei Bonsu of the CSIR-Crops Research Institute in Kumasi led a four-person team. They published in the journal Environmental Monitoring and Assessment.
What does a hazard index above 1.0 mean?
It means the combined intake of the metals passes the level regarded as safe for non-cancer harm. The reviewers found this in every mining community where they could calculate it.
Sources: Graphic Online, Toxic metals from galamsey found in vegetables across mining districts – Study, 21 October 2026; Bonsu et al., Potentially toxic element contamination in Ghana’s vegetable value chain, Environmental Monitoring and Assessment, 26 September 2026; GhanaWeb, New study finds toxic metals in some vegetables grown in galamsey areas, 21 October 2026.
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief