Heavy metals in soil - such as cadmium, lead, mercury, and arsenic - pose significant risks to human health. Scientific studies have revealed how these elements can enter the human body through various pathways, including the consumption of contaminated food and water, inhalation of dust, and dermal contact. Once inside the body, they tend to accumulate in vital organs, leading to a range of adverse health effects.
)
A recently published study, a joint effort of scientists from Germany, Sudan, and the United States, examines the health risks for 10 potentially toxic elements (PTEs) across 9 land-use types in Sudan. It looks at the heavy metals like arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb) in soils affected by industrial processes, agriculture, waste dumping, and other activities.
The study highlights the ingestion of contaminated crops as one of the most common pathways of exposure. Direct skin contact with contaminated soil further increases exposure risks, particularly for communities living near industrial areas, waste dumps, or agricultural lands heavily reliant on pesticides and fertilizers. Scholars suggest that cobalt and cadmium, commonly found in these agricultural inputs, are likely the primary sources of contamination in both urban and rural agricultural lands.
According to the research, children are especially vulnerable. Their developing bodies absorb heavy metals more readily, and behaviours such as playing in the soil or mouthing objects amplify their exposure. Once absorbed, metals like cadmium and lead tend to bioaccumulate, impairing vital organs such as the kidneys, liver, and brain.
Key findings per elements:
Arsenic (As): Found in industrial and urban agricultural soils, arsenic levels in Sudan significantly exceed safe thresholds for children, posing serious risks of developing lymphomas.
Cadmium (Cd): Concentrations in farmland surpass permissible limits, exposing both children and adults to elevated risks of lung cancer and kidney damage.
Nickel (Ni): Identified as the most concentrated carcinogenic contaminant in Sudanese soils, nickel levels in industrial zones and farmlands are four times above safety limits, linked to oral and bowel cancer.
The authors strongly recommend the development of effective management strategies to mitigate the potential human health risks caused by PTEs in the Sudanese soils. Moreover, the ongoing armed conflict in Sudan, which began in 2023, is likely to exacerbate soil pollution from PTEs, further elevating risks to human health.
More information available at: https://www.sciencedirect.com/science/article/pii/S0048969724083542