Peat soil additive slashes cadmium in rice, but raises arsenic
Li B, Zhang T, Zhang Q, Wang S, Zheng S
Soil Health
If you grow vegetables in soil near old industrial sites or busy roads, this shows how a simple organic amendment can lock up one toxic metal in the ground while accidentally freeing up another, a tradeoff worth understanding before treating contaminated garden soil.
Rice grown in polluted soil can soak up both cadmium and arsenic, two metals that are bad for human health. Researchers found that mixing a peaty organic material into the soil, or an extract made from it, dramatically reduced how much cadmium ended up in rice grains by changing how iron behaves in the flooded soil. But the same treatment made the arsenic problem slightly worse, showing that fixing one contaminant can shift the balance for another.
Key Findings
CaCl2-extractable cadmium in soil dropped 14.40-95.75% across treatments after 60 days, while available arsenic rose 16.46-64.11%
Grain cadmium fell 40.85-69.41% in both early and late rice crops, while grain arsenic increased 13.10-37.20%
The amendments shifted iron oxides from crystalline to amorphous forms and reduced iron/manganese in root iron plaque, decreasing cadmium retention but boosting arsenic capture there
chevron_right Technical Summary
Adding a natural soil material called woody peat (or its extracted humate) to contaminated rice paddies can cut toxic cadmium in rice grains by up to 69%, though it comes with a tradeoff of slightly increasing arsenic uptake.
Abstract Preview
Original paper
Iron fractionation and iron plaque-mediated effects of woody peat and its humate on cadmium and arsenic behavior in a ricesoil system.
Cadmium and arsenic (Cd/As), which are prevalent metal(loid) contaminants in paddy soils, pose dual threats to food safety and human health. The efficacy of woody peat and its alkali-extracted huma...
open_in_new Read full abstractAbstract copyright held by the original publisher.
Species Mentioned
Was this useful?
Want to tell us more? (optional)
Thanks for the note!
Something went wrong — please try again.
Too many submissions. Try again in an hour.
Gene editing removes 97% of celiac-triggering proteins from bread wheat
It could mean that people with celiac disease — roughly 1 in 100 worldwide — may one day safely eat bread made from real wheat, without sacrificing the taste...
Rice is a cereal grain and in its domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species Oryza sativa —or, much less commonly, Oryza glaberrima. Asian rice was domesticated in China some 13,500 to 8,200 y...