Agricultural Soils Surpass Oceans as Global Microplastic Hotspot, Threatening Food Security
A landmark study led by Murdoch University researchers reveals that agricultural soils have quietly become the planet’s primary repository of microplastics, accumulating concentrations 23 times higher than those found in ocean waters, Earth.com revealed. This invisible contamination, driven by decades of plastic mulch use, sewage sludge fertilization, and atmospheric deposition, now permeates the very foundation of global food systems.
The research team, spearheaded by PhD candidate Joseph Boctor, documented how microplastics carrying up to 10,000 unregulated chemical additives infiltrate crops through root systems and leaf surfaces. Their analysis of global data demonstrates severe ecological consequences, including a 35% reduction in nitrogen uptake by peanut plants and measurable declines in photosynthetic efficiency across multiple staple crops.
Of particular concern are findings that common bioplastics marketed as sustainable alternatives—such as PLA and PBAT—continue to disrupt soil microbiology and plant development. The contamination cycle completes when these particles appear in human food supplies, with apples found to contain 233,000 microplastic particles per gram. Adults now unknowingly consume approximately one credit card’s weight in plastic weekly, with detectable particles present in human placenta, bloodstreams, and major organs.
The study, published in Environmental Sciences Europe, calls for immediate international policy coordination to address regulatory gaps. With no current standards governing microplastic levels in agricultural soils, researchers warn the situation threatens to permanently degrade both ecosystem health and food security worldwide.
