Iron solubility in mineral dust and aerosol generated from soil samples

Abstract

Studies of Fe solubility are vital to improve the knowledge on the speciation of Fe in the mineral aerosol and its bioavailability to organisms in the marine environment. During atmospheric transport, mineral aerosol particles undergo several processes that may increase its solubility. Most important are the changes in pH, which occur during cloud formation. In this work we have simulated the cycle of condensation and evaporation of clouds in soil samples and compared the results with samples from dry deposition of natural mineral aerosol collected on the island of Gran Canaria. The results show the effectiveness of the simulation process, since there is an increase in the solubility of Fe, resulting in aerosol solubility comparable to that found in natural aerosol samples. This process does not include the complexity of the processes that undergo mineral aerosol during atmospheric transport but it can be used as an approximation. It is necessary to continue studying mineral aerosol and in particular the behaviour of Fe within them.