delware environmental institute

The softer side of x-rays: Researchers use NSLS to probe cadmium-contaminated soil

The softer side of x-rays: Researchers use NSLS to probe cadmium-contaminated soil

Researchers at the University of Delaware in collaboration with scientists at Brookhaven National Laboratory have shown that the chemical structure and bioavailability of cadmium-contaminated soil changes with the flooding and drying cycles of lowland rice culture.

Cadmium is a natural element found in some soils, but human activities like mining and smelting release cadmium into the environment at higher concentrations than normal. This can create a toxic situation for organisms living nearby if the cadmium binds to organic elements and enters the food chain.

In 2003, the International Water Management Institute reported that the Mae Sot district of Thailand had “considerable amounts” of cadmium and zinc in its irrigation water, paddy soils, and rice grain. Saengdao Khaokaew, a Thai graduate student at the University of Delaware and the principal investigator of the study, wanted to determine whether the cadmium remained in inert mineral form or attached to organic sulfur and carbon as a result of the flooding and draining cycles used to cultivate rice. (full article)