Biomedical Engineering Reference
In-Depth Information
TABLE 11.5
Generic Matrix of Most Needed Inventory Efforts
a
Raw
Materials
Manufacturing
Use
Disposal
Indirect processes
- inventory
components
-
-
-
-
Idem
conventional
Idem
conventional
Idem
conventional
Idem
conventional
“Nano-product”-
specific processes
- inventory
components
NA
+++
++
+
/
To be
developed
To be developed
in some cases/
Idem
conventional
Idem
conventional
processes
until now
Direct nanoparticle
emissions
NA
+++
+++
+++
To be
characterized
a
The importance of inventory efforts is reflected by the following code in decreasing order: +++
> ++ > + > -. NA: not applicable.
/
To be
characterized
To be
characterized
nanoproducts; (ii) the nanoproduct-specific inventory components that focus
on direct material and energy inputs, and classic toxic emissions for the main
manufacturing pathways, as well as during the use stage and disposal of the
nanoproducts; and (iii) the direct nanoparticle emissions from the consid-
ered processes in each of the life cycle stages. Table 11.5 shows the general
importance of these three inventory components through the nanoproduct
life cycle in terms of required efforts (in the present context).
The processes associated with the supply of inputs into the nanoproduct
life cycle (e.g., the matrix in which a nanomaterial is to be embedded) are the
least demanding in terms of data collection, as they typically refer to pro-
cesses used in conventional materials, and hence are already well covered by
publicly available LCI databases or LCA software/tools. On the other hand,
the two other inventory components—direct nanoparticle emissions and
nanoproduct-specific process inventory—require further efforts (see color-
coding in Table 11.5); these are developed in the following, after a brief status
of the quantification of nanoparticle releases throughout the life cycle.
11.3.2.1 Quantification of LC Emissions of Nanoparticles: A Status
11.3.2.1.1 Measurements of Nanoparticle Emissions: Many Challenges Left
What would be the needed information for quantifying releases and allow-
ing characterization in LCA studies? To allow a proper assessment of toxic-
ity exerted by the nanoparticles (see Section 11.3.3), more information than
bulk chemicals are needed. Ideally, apart from a proper characterization of
the process under study, knowledge on the size distribution of the emitted
nanoparticles, including distinction between the (i) aggregated nanopar-
ticles, (ii) the matrix-bound nanoparticles, (iii) the single nanoparticles,
