Abstract
Massive quantities of nanomaterials are continuously produced and distributed by natural processes that occur in the atmosphere, hydrosphere, and soils of the Earth. Manufactured nanomaterials, by comparison, provide a tiny addition to the global inventory of naturally-occurring nanomaterials, yet they form the basis of the nanotechnology revolution and its enormous and rapidly growing economic impact (presently on the order of $1 trillion annually, and rising rapidly). However, beyond naturally-occurring and manufactured nanomaterials, it is also critical to consider incidental nanomaterials. These exist due to human activity, but their formation is completely unintentional, and most often unexpected. Even more telling and in the great majority of cases, they go completely unnoticed.
It is important to recognize that there are two principal types of incidental nanomaterials. Direct incidental nanomaterials form directly from some human activity, for example, fullerene formation due to the burning of fuel in diesel engines, or silver sulfide nanoparticle formation in waste water treatment plants. Indirect incidental nanoparticles form as a result of anthropogenic Earth modification, followed by natural production of nanomaterials that would not have occurred without the original human impact. An example is what occurs around mining activity that modifies normal Earth surface processes, resulting in the Earth's production of nanomaterials that would not normally be present at that place and time.
In this talk, multiple examples will be given of recently discovered direct and indirect incidental nanomaterials related to mining and its legacy. Representatives of indirect incidental nanomaterials are schwertmannite and green rust nanominerals observed in post-mining environments that are linked to the mobility of toxic heavy metals. We will also show an example of a direct incidental nanomaterial, a highly reactive oxygen-deficient titanium oxide phase, which is ultimately produced in coal-burning power plants and also another legacy of mining.
In this talk, multiple examples will be given of recently discovered direct and indirect incidental nanomaterials related to mining and its legacy. Representatives of indirect incidental nanomaterials are schwert mannite and green rust nanominerals observed in post-mining environments that are linked to the mobility of toxic heavy metals. We will also show an example of a direct incidental nanomaterial just discovered, a highly reactive oxygen-deficient titanium oxide phase, which is ultimately produced in coal-burning power plants. This is also a portion of the legacy of mining.
