Читать книгу Microbial Interactions at Nanobiotechnology Interfaces - Группа авторов - Страница 28

Based on their origin, NMs are classified as natural and synthetic NMs. The NMs that are produced by biological species or anthropogenic activities in nature without human intervention are called natural NMs. The NMs formed in nature are present throughout earth's atmosphere, hydrosphere, and lithosphere. This may include the NMs present in whole troposphere, oceans, sea, rivers, lake, groundwater, rocks, lava, soils, even microorganism, and higher organisms (Hochella, Spencer, & Jones, 2015; Sharma et al., 2015). Synthetic NMs are the NMs that are synthesized through physical, chemical, biological, or hybrid methods besides the materials that are produced from engine exhaust, smoke, and mechanical grinding (Wagner et al., 2014). Even though synthetic NMs are more advantageous as aforementioned, the major problem is predicting the fate and behavior of the materials in the environment. Currently there are a lot of strategies to perform the risk assessment of the synthetic NP in various environmental conditions. Still extrapolating the behavior of synthetic NMs from existing knowledge is a major challenge.