Nanoparticles toxicity and their routes of exposures.

The new scientific innovation of engineering nanoparticles (NPs) at the atomic scale of 100 nm or less, has led to numerous novel and useful wide applications in electronics, chemicals, environmental protection, biological medicine. Manufacturers and consumers of the nanoparticles-related industrial products however, are likely to be exposed to these engineered nanomaterials which have various physical and chemical properties. These nanosize particles are likely to increase an unnecessary infinite toxicological effect on animals and environment, although their toxicological effects associated with human exposure are still unknown. In order to understand the effects of these exposures, this review seeks to examine the various toxicological portal routes associated with NPs exposures. These NPs can enter the host systems via skin spores, debilitated tissues, injection, olfactory, respiratory and intestinal tracts. These uptake routes of NPs may be intentional or unintentional. Their entry may lead to various diversified adverse biological effects. Until a clearer picture emerges, the limited data available suggest that caution must be exercised when potential exposures to NPs are encountered. Methods used in determining NPs portal of entry into experimental animals include pharyngeal instillation, injection, inhalation, cell culture lines and gavage exposures. This review also provides a step by step systematic approach for the easy identification and addressing of occupational health hazards arising from NPs.