Metal menace: Toxic soil threatens global agriculture
Global agriculture is facing a significant challenge. Scientists are raising alarms about soil pollution and the infiltration of substances such as arsenic, lead, and cadmium into food. According to the latest analyses, up to 17% of the world's arable lands contain heavy metals.
Global agriculture is grappling with a serious environmental problem. As demonstrated by analyses conducted by scientists for the American Association for the Advancement of Science (AAAS) and published in the scientific journal "Science", as much as 242 million hectares of soil worldwide is contaminated with toxic heavy metals, which constitutes one-sixth of the world's arable land. These alarming data have serious consequences for both the environment and public health.
They analysed over 1000 regional studies from around the world
A research team, including Deyi Hou, Xiyue Jia, Liuwei Wang, Steve P. McGrath, Yong-Guan Zhu, Qing Hu, Fang-Jie Zhao, Michael S. Bank, David O’Connor, and Jerome Nriagu, has gathered data from over 1,000 regional studies worldwide, as well as employing machine learning technology.
"This map also illustrates how metal pollution is independent of human borders; to tackle this problem, countries will have to work together," said Dr. Liz Rylott, Senior Lecturer in the Department of Biology at the University of York, to "The Guardian." "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," commented the expert.
Which metals contaminate the soils?
Research has found that approximately 14-17% of the world's arable lands are polluted by metals such as arsenic, cadmium, cobalt, chromium, copper, nickel, and lead. The levels of these substances exceed safety thresholds, posing a threat to crop quality and public health. Dr. Liz Rylott from the University of York emphasises that heavy metals can lead to skin changes, limitations in nerve and organ function, and even cancers.
The sources of pollution include both natural factors and human activities. The effects of contamination are long-term, including risks to ecosystems, reduced crop yields, and threats to water quality. Bioaccumulation in livestock poses further threats to food safety.
The problem will continue to deepen
In the face of increasing demand for rare earth metals for green technology production, scientists are warning of a worsening problem. Between 900 million and 1.4 billion people globally live in high-risk areas for metal contamination. Cadmium is the most widespread toxic metal, particularly in South and East Asia, the Middle East, and Africa.
Dr. Rylott also highlights that the problem of heavy metal pollution crosses national borders and requires international cooperation. The effects primarily impact low and middle-income countries, exacerbating poverty issues. The impact of these contaminated crops entering global food networks is not entirely clear, adds the expert.
