About one sixth of global cropland is contaminated by toxic heavy metals, researchers have estimated, with as many as 1.4 billion people living in high-risk areas worldwide. From a report: Approximately 14 to 17% of cropland globally — roughly 242m hectares — is contaminated by at least one toxic metal such as arsenic, cadmium, cobalt, chromium, copper, nickel or lead, at levels that exceed agricultural and human health safety thresholds.
The analysis, which was conducted by the American Association for the Advancement of Science (AAAS) and published in the journal Science, collected data from more than 1,000 regional studies across the globe, as well as using machine learning technology. Dr Liz Rylott, a senior lecturer in the department of biology at the University of York, who was not involved in the research, said: “These findings reveal the deeply worrying extent to which these natural poisons are polluting our soils, entering our food and water, and affecting our health and our environment. Often collectively called heavy metals, these elements cause a range of devastating health problems, including skin lesions, reduced nerve and organ functions, and cancers.”
Toxic metal pollution in soil originates from both natural and human activity. Contaminated soil causes significant risks to ecosystems and human health as well as reducing crop yields, jeopardising water quality and food safety owing to bioaccumulation in farm animals. Toxic metal contamination can persist for decades once pollution has been introduced into soil.