Plants emit sulfate-, phosphate- and metal-containing nanoparticles

The presence of engineered and natural nanoparticles in the atmosphere is of concern for health and climate. Actually there are few studies on the release of natural nanoparticles from plants in the air. Here, we built a device to collect exhaled substances from four plant species in China. The structure and composition of the exhaled substances were analyzed by transmission electron microscopy. The results show that plants emit a large number of nanoparticles with size mostly between 50 and 300 nm. These nanoparticles usually contain sulfate, phosphate and metals. We discuss the sources of plant nanoparticles, and the implication of sulfate-containing nanoparticles for climate cooling.