For each of the environmental and health hazards
mentioned earlier under “Purpose” we will determine:
the character and most important risk (e.g. which health effect, short
term and/or long term health risks, public safety risk, short term
and/or long term environmental risk) and most important exposures (e.g.
exposure levels duration and size of exposed populations)
dose-response characteristics and no effect levels have to be
identified and compared to the exposures to humans and the environment
the particular data requirements and how they have been established
(distinguishing between generic data that is readily available,
specific empirical data that needs to be established and data that can
be inferred/interpreted or calculated)
how to deal with uncertainty
the life cycle stages along which the risk occurs (application or use,
recycling and final treatment or disposal)
risk assessment methods applicable to nanomaterials and associated
products.
One of the key challenges in this context is to understand to what extent
existing risk assessment approaches and support tools are valid and/or need
to be refined or modified to account for some of the particular features
and uncertainties associated with nanomaterials.
For example, toxic dose levels for bulk chemicals may not be applicable for
nanomaterials based on the same chemical. Also, the long term behaviour of
nanomaterials in the environment may be different from the behaviour of
bulk chemicals. Understanding how such uncertainties can be incorporated
into existing risk assessment approaches, if at all, is one of the main
challenges for the work.
