New study reignites debate over nanoparticle safety

An international research team has traced how nanoparticles from substances such as cosmetics can end up in food crops and have published their findings in the journal ACS Nano. The team was led by Jorge Gardea-Torresdey of the University of Texas in El Paso and also included scientists from the University of California and the European Synchrotron Radiation Facility.

They tracked zinc oxide and cerium dioxide, both used in sun care products, and tested them in soybeans. Zinc was shown to dissolve and accumulate throughout the plants, whereas the cerium did not dissolve into plant tissue, though it still reaches the food chain and the next generation of plants.

"A growing number of products containing engineered nanoparticles are in the market and eventually they will get into the soil, water and air,” said Gardea-Torresdey.“

As zinc is present in most plants, it didn’t come as a surprise that zinc from the nanoparticles in the soil can enter into the plant tissue,” added his colleague, Hiram Castillo. “But plants can also assimilate more dangerous elements like cadmium or arsenic which, when used in nanoparticles, might pose a real threat.”