2.2.2 Ultrafine or Incidental Nanomaterials
Ultrafine or incidental NMs are defined as the NMs fabricated indeliberately either
directly or indirectly by anthropogenic processes. These NMs are produced by
industries non-intentionally as a by-product of various processes. Other than
industries, ultrafine nanoparticles (NPs) released from automobile engine exhausts,
household combustion processes like cooking, smelting, fires, fuel combustion,
welding fumes, and volcanoes fuel also (Oberdörster et al. 2005b; Duffin et al.
2007). It was documented that fullerenes (one type of NMs) are released from candle
fumes, burning gas, and biomass, as a by-product of corrosion products (Barceló and
Farré 2012). Aerosol research, environmental and occupational health communities
used the term ‘ultrafine’ to define airborne particles in the range of 1–100 nm
(Barceló and Farré 2012).
2.2.3 Natural Nanomaterials
These NMs are defined as the nanosubstances made by nature through biogeochemical processes, without anthropogenic connection. Natural NMs have always been
Fig. 2.1 Different wet
chemical methods used for the
fabrications of nanoparticles
26
V. Dogra et al.
Ultrafine or incidental NMs are defined as the NMs fabricated indeliberately either
directly or indirectly by anthropogenic processes. These NMs are produced by
industries non-intentionally as a by-product of various processes. Other than
industries, ultrafine nanoparticles (NPs) released from automobile engine exhausts,
household combustion processes like cooking, smelting, fires, fuel combustion,
welding fumes, and volcanoes fuel also (Oberdörster et al. 2005b; Duffin et al.
2007). It was documented that fullerenes (one type of NMs) are released from candle
fumes, burning gas, and biomass, as a by-product of corrosion products (Barceló and
Farré 2012). Aerosol research, environmental and occupational health communities
used the term ‘ultrafine’ to define airborne particles in the range of 1–100 nm
(Barceló and Farré 2012).
2.2.3 Natural Nanomaterials
These NMs are defined as the nanosubstances made by nature through biogeochemical processes, without anthropogenic connection. Natural NMs have always been
Fig. 2.1 Different wet
chemical methods used for the
fabrications of nanoparticles
26
V. Dogra et al.