In its May issue the peer-reviewed scientific journal Nature Communications published an article on a new technique developed by Canadian researchers to visualize and analyze exposure to nanomaterials (Sykes et al. 2014). Sykes and colleagues show that the skin is an important site of nanoparticle accumulation and that this accumulation may be detected using ultraviolet light. The researchers found exposure to gold particles to result in visibly blue skin in mice, whereas quantum dot exposed mice fluoresce under ultraviolet excitation. They propose that the skin analysis may be a simple strategy to assess nanoparticle exposure. In a press release published by the Harvard School of Public Health, senior author Philip Demokritou states that so far risk assessment of nanoparticles was limited by the difficulties in quantifying exposure levels without taking tissue samples from the liver and spleen. The U.S. Food and Drug Administration (FDA) does not require manufacturers to carry out risk assessments of nanoparticles for which the bulk material is considered safe. However, there is evidence that nanomaterials may be more harmful in their nanoform than in the bulk form. The new technique gives an indication of internal exposure and is thus an important step in resolving some of the difficulties encountered in risk assessments of nanomaterials, Phys.org concludes.
Marge Dywer (March 28, 2014). “Researchers develop technique to measure quantity, risks of engineered nanomaterials delivered to cells.” Harvard School of Public Health.
Sykes, E. et al. (2014). “Nanoparticle exposure in animals can be visualized in the skin and analysed via skin biopsy.” “Estimating the effective density of engineered nanomaterials for in vitro dosimetry.” Nature Communications 5, 3796.