Nanoparticles, potential hazards

Abstract The present paper discusses classification of nano-objects, which is based on their size, morphology and chemical nature. The subject of nanochemistry includes those nano-objects whose chemical properties depend on size and morphology, such as spheroidal molecules, anisotropic (2D) and isotropic (ID) nanoparticles, nano-clusters and nanophases. Nanophase is a nano-dimensional part of the microphase whose properties depend on its size. The potential health hazards of nano-objects are associated with their capability of penetrating the body through inhalation, digestion or the skin. 

Valant J, Drobne D, Sepcic K, Jemec A, Kogej K, Kostanjsek R (2009) Hazardous potential of manufactured nanoparticles identified by in vivo assay. J Hazard Mater 171 160-165... 

In addition to obtaining information to perform a hazard and dose-response evaluation, an exposure assessment will need to be conducted to estimate and characterize any potential risks associated with nanomaterials. If the hazard identification process reveals that a nanomaterial is iimocuous and does not pose a potential for eliciting any adverse human health or environmental effects, it may not be necessary to conduct additional toxicological studies or an extensive exposure assessment. In cases where the hazard evaluation determines a potential for adverse effects for the nano-material, in vitro and/or in vivo studies may be conducted to evaluate the potential for systemic exposure from inhalation, oral, or dermal penetration. Such information may help to refine the exposure assessment by providing estimates of internal doses. Much of the published human toxicological and epidemiology data relate to airborne exposme to nanoparticles or ultrafine particles. However, there are additional routes by which humans can be exposed to nanomaterials that may need to be considered, including ... 

Hesterberg, Thomas W., Christopher M. Long, Charles A. Lapin, Ali K. Hamade, and Peter A. Valberg, Diesel Particulate (DEP) and Nanoparticle Exposures What do DEP Human Clinical Studies Tell Us About Potential Health Hazards of Nanoparticles , Inhalation Toxicology 22, 679-694 (2010). 

Carbon dots. Carbon dots (C-dots) refer to small carbon nanoparticles endowed with a bright photoluminescence, similar to the one described for quantum dots (see below). However C-dots do not contain heavy-metal atoms with potential health and environmental hazards. Therefore they have been proposed, along with silicon nanoparticles (see below) as potential alternatives to quantum dots for bioimaging. ° ... 

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