{
  "id": 28587,
  "title": "Researchers use hemp, rock dust and biochar to scrub forever chemicals from farm soils",
  "url": "https://urgent.news/2026/07/24/researchers-use-hemp-rock-dust-and-biochar-to-scrub-forever-chemicals",
  "topic": "science",
  "section": "Science",
  "published": "2026-07-24T12:00:00.000Z",
  "source": {
    "name": "Anthropocene Magazine",
    "slug": "anthropocene-magazine",
    "url": "https://www.anthropocenemagazine.org/2026/07/researchers-use-hemp-rock-dust-and-biochar-to-scrub-forever-chemicals-from-farm-soils/"
  },
  "original_language": "en",
  "account": "A study led by researchers from Yale University proposes a cost-effective, eco-friendly method to remove 'forever chemicals' like PFAS from agricultural soils. This innovative three-step strategy involves the use of hemp plants, rock dust, and biochar.\n\nPFAS, which are used in various products, have contaminated soil and pose a threat to crop production. In some US states, farmlands have been forced to shut down due to unsafe PFAS levels. The research team examined two types of PFAS – PFOS and PFOAS – and their plan focuses on combating this environmental issue.\n\nFirst, they applied basalt rock dust to the soil, a technique known for sequestering carbon dioxide. This process alters the soil pH, making PFAS more accessible to plants like hemp and perennial grasses. The researchers then analyzed the growth of these plants and the effects of converting their cuttings into biochar – a process that neutralizes the chemicals' toxicity. Finally, they considered spreading the biochar across other heavily contaminated farmlands, effectively trapping and preventing PFAS from entering runoff and further polluting ecosystems.\n\nThe team found that applying rock dust accelerated the decline of PFOS by 20-40%. While the impact was less significant for PFOAS, PFOS are considered a higher priority in terms of regulation. By recycling plant waste into biochar and spreading it over contaminated farmlands, the researchers estimate that they could reduce PFAS runoff by 95%.\n\nOverall, their integrated approach could lower PFAS levels in US soils below acceptable limits within a decade. Additionally, the combined use of rock dust and biochar would eliminate 10.5 million metric tons of carbon dioxide annually if applied nationwide. Conventional clean-up methods, which involve excavating and burning large amounts of soil, would cost an estimated $8 trillion. In contrast, the researchers' method would only require about $1.46 per hectare annually.\n\nAlthough the study focused on the US, its authors highlight its global relevance. In Europe, 50% of sewage sludge – around 10 million tons – is spread over farmland each year, while China also applies the same amount. In the UK, the figure stands at 70%. The researchers conclude that their solution is broadly applicable, allowing farmers to continue working their land while restoring soil health.",
  "summary": "A Yale study finds that combining three low-cost interventions could bring contaminated soils below safety thresholds within a decade, at a fraction of conventional cleanup costs.",
  "key_points": [
    "Researchers propose hemp, rock dust, and biochar method for PFAS removal",
    "Basalt rock dust applied to soil to increase PFAS accessibility to plants",
    "Biochar conversion reduces PFAS toxicity and prevents runoff contamination"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}