The term nanomaterials refers to materials that have at least one dimension (height, width or length) that is smaller than 100 nanometres (10−7 metre), which is about the size of a virus particle. This particular size dimension represents a major characteristic of manufactured nanomaterials (MNMs). The unique properties of MNMs may result in better paints, better drugs and faster electronics. However, for the same reason, MNMs may also present health hazards that differ from those of the substance in bulk form, and may require different test methods for hazard, exposure and risk assessment from their bulk material counterparts.
WHO proposes these guidelines to policy makers and professionals in the field of occupational health and safety
with recommendations on how best to protect workers from the potential risks of MNMs………
http://www.who.int/occupational_health/publications/manufactured-nanomaterials/en/
