Colloidal stability of nanoparticles derived from simulated cloud-processed mineral dusts

Abstract Laboratory simulation of cloud processing of three model dust types with distinct Fe-content (Moroccan dust, Libyan dust and Etna ash) and reference goethite and ferrihydrite were conducted in order to gain a better understanding of natural nanomaterial inputs and their environmental fate and bioavailability. The resulting nanoparticles (NPs) were characterised for Fe dissolution kinetics, aggregation/size distribution, micromorphology and colloidal stability of particle suspensions using a multi-method approach. We demonstrated that the: (i) acid-leachable Fe concentration was highest in volcanic ash (1 mMg − 1 dust) and was followed by Libyan and Moroccan dust with an order of magnitude lower levels; (ii) acid leached Fe concentration in the   Libyan dust). The common occurrence of Fe-rich “natural nanoparticles” in atmospheric dust derived materials may indicate their more ubiquitous presence in the marine environment than previously thought.