Pulse Brain · Growing Health Evidence Index
Tier 1 — Meta-analysis / systematic reviewPeer-reviewed

Global soil pollution by toxic metals threatens agriculture and human health

Deyi Hou, Xiyue Jia, Liuwei Wang, S. P. McGrath, Yong‐Guan Zhu, Qing Hu, Fang‐Jie Zhao, Michael S. Bank, David O’Connor, Jerome O. Nriagu

Science · 2025

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Summary

This global meta-analysis synthesised soil pollution data from 1,493 regional studies across 796,084 sampling points to map toxic metal contamination and identify areas of agricultural and public health concern. Machine learning models revealed a previously unrecognised high-risk metal-enriched zone in low-latitude Eurasia linked to climatic, topographic, and anthropogenic factors. The findings indicate that toxic metal soil pollution affects a substantial proportion of global cropland and poses exposure risks to nearly 1 billion people, representing a significant but underappreciated feature of the Anthropocene.

UK applicability

While the study is global in scope, UK soils may face different metal contamination profiles and risk levels depending on regional geology, industrial history, and agricultural practices; the methodology and thresholds could inform domestic soil monitoring and food security assessments, though UK-specific data and regional risk mapping would be needed to determine applicability to UK farming and public health contexts.

Key measures

Soil concentrations of arsenic, cadmium, cobalt, chromium, copper, nickel, and lead at 796,084 sampling points; proportion of cropland exceeding agricultural and health thresholds; population exposure in high-risk zones

Outcomes reported

The study quantified the global distribution of soil pollution by seven toxic metals (arsenic, cadmium, cobalt, chromium, copper, nickel, and lead) using machine learning to map areas exceeding agricultural and human health thresholds. It identified that 14–17% of global cropland is affected by toxic metal pollution and estimated that 0.9–1.4 billion people live in regions of heightened public health and ecological risk.

Theme
Farming systems, soils & land use
Subject
Pesticides, contaminants & food safety
Study type
Meta-analysis
Study design
Meta-analysis
Source type
Peer-reviewed study
Status
Published
Geography
Global
System type
Arable cereals
DOI
10.1126/science.adr5214
Catalogue ID
BFmowc2359-n75uwu

Topic tags

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