Nanotechnology Safety Initiative
NTP Nanotechnology Projects
Ongoing research activities are initially focusing on 4 classes of materials:
Initial focus is on nanoscale titanium dioxide and zinc oxide due to their presence in cosmetics. Ongoing and/or planned activities:
- Characterization of size, crystallinity, and coating of these metal oxides in representative commercial sunscreens
- Evaluation of photoactivation of titanium dioxide in in vitro, ex vivo, and in vivo models
- Dermal penetration of titanium dioxide in in vivo and in vitro models
- Phototoxicology of titanium dioxide in mice
- Photocarcinogenicity of titanium dioxide in transgenic mice
Fluorescent Crystalline Semiconductors (Quantum Dots)
Initial focus is on cadmium selenide/zinc sulfide spheres and rods of varying sizes and surface chemistry as a model system to test hypotheses about role of size and surface chemistry on tissue distribution. Ongoing and/or planned activities:- Synthesis and characterization of specific materials
- Development of quantitative fluorescent microscopy system and IPC-mass spectroscopy approach for evaluating tissue levels
- Quantitative evaluation of the tissue distribution following dermal and systemic routes of exposure
Initial focus is on carbon based fullerenes of varying cage size and surface derivatisation. Ongoing and/or planned activities:
- Physicochemical characterization of procured materials and formulation development
- In vivo repeat dose toxicity studies following oral exposure
- Pulmonary toxicity and evaluations following a single intratracheal instillation
- Immunotoxicological evaluation of fullerene C60
Initial focus is on single walled carbon nanotubes. Through a NIEHS-NIOSH interagency agreement NTP is supporting the development of exposure systems for inhalation toxicity studies of single walled nanotubes.
Web page last updated on February 07, 2006