Environmental profile assessments

Building on this characterization of nanotechnology, the concurrent ongoing assessment approach to the prospective TA is followed by an ascertainment of sustainability effects using specific application examples in comparison to existing products and processes, whereby, in accordance with the life cycle assessment method, the focus is on the substance and energy flows and their associated ecological opportunities and risks. The involvement of current fields of application means that the time frame of this approach is accordingly much, much smaller than is the case with the technology characterization. In such life cycle assessment approaches, only those developments that are almost ready for market can be assessed. And comparisons can only be made in those areas of application of the new technology that compete with already existing technologies, processes, or products (and for which the corresponding data is already available).

Since the appraisal of potential environmental impacts is the top priority, the environmental profile assessments for the in-depth case studies are modeled in their approach on the life cycle assessment methodology. However, they are unable to meet the high standards required, since the data available for new products and processes - and, to an extent, also for those products and processes used in the comparisons - is far from complete. The life cycle assessment is the most extensively developed and standardized methodology for assessing the environmental aspects and product-specific potential environmental impacts of a product. Many potential applications of nanotechnology will, on the basis of fundamental deliberations (and aspects of the technology characterization), be associated with desires for the realization of enormous resource efficiency improvements. The potential validation of these desires, that is, the compari

19 With all the hope for an economic upswing, growth and prosperity, that is generally associated with such a characterization as an enabling technology or fundamental innovation, whereby, of course, even in the case of an extensive economic structural change, not only winners but also losers must be expected. The latter will be particularly found in those very sectors and enterprises that are not capable of replacing their "old" technologies and solutions with nanotechnical innovations.

son of the eco-efficiency potentials of nanotechnological solutions, products, and processes to existing applications, is possible with the help of the life cycle assessment.

In accordance with EN ISO 14040, a life cycle assessment consists of the following steps:

• Definition of the goal and scope of the investigation

• Life cycle inventory analysis

• Life cycle impact assessment

• Life cycle interpretation

The following illustration makes clearer the relationship between these steps.

Fig. 4. Steps in the preparation of a life cycle assessment20

The directional arrows between the individual LCA steps should make clear the iterative nature of the process, i.e., the results of further steps are always fed back into the process, possibly resulting in further changes and iterations.

In the first step, the goal and the scope of the study are defined. The second step, the life cycle inventory analysis, involves the collection, compilation, and calculation of data. The life cycle assessment, as its name suggests, generally looks at a product or service over its entire life cycle. Specific substance and energy data therefore must be collected for each life cycle stage. Essential data includes, on the input side, the consumption

20 Source: DIN EN ISO 14040 (1997)

of raw and ancillary materials, including energy inflows, and on the output side, product data, including air and water emissions and waste data. In the life cycle impact assessment the data of the life cycle inventory analysis is organized (classification) and summarized (characterization) according to its environmental relevance. In this way, the resource drawdowns and emissions that occur over the course of the product life cycle are brought into the context of environmental impacts in debate among experts and the public. The following table lists some examples of some impact categories and the substances contributing to them.21

Table 5. Impact categories and contributing substances22

Impact category Contributing substances and factors

Demand on resources Consumption of renewable and non-renewable resources (crude oil, natural gas, coal, minerals, lumber, etc.) Carbon dioxide (CO2 ), methane (CH4), nitrous oxide (N2O), among others chlorofluorocarbons (CFCs), brominated and halo-genated hydrocarbons, among others Volatile organic hydrocarbons (VOCs), organic solvents, airborne particulates, benzene, heavy metal compounds (arsenic, cadmium, mercury, lead, nickel, etc.) Sulfur dioxide (SO2), nitrogen oxides (NOx), fluorides, hydrogen fluoride, hydrogen chloride, carbon monoxide (CO), among others

Sulfur dioxide (SO2), nitrogen oxides (NOx), fluorides, hydrogen fluoride, hydrogen chloride, lead (Pb), cadmium (Cd), copper (Cu), mercury (Hg), zinc (Zn), chromium (Cr), nickel (Ni), adsorbable organic halogens (AOX), among others

Nitrogen oxides (NOx), methane (CH4), volatile organic hydrocarbons (VOCs), among others Sulfur dioxide (SO2), nitrogen oxides (NOx), ammonia, (NH3 ), hydrochloric acid (HCl), hydrogen fluoride (HF), among others

Aquatic eutrophication Nitrate (NO3-), ammonium (NH4+), chemical oxygen demand (COD), total phosphorous, total nitrogen, among others

Terrestrial eutrophica- Nitrogen oxides (NOx), ammonia (NH3), among others

21 The toxicities and the impact on natural area resources (in part also the use of these resources) are not being presently being taken into consideration in most life cycle assessments because of the problems of standardization and quantization.

22 Source: Ankele & Steinfeldt (2002)

Greenhouse effect

Stratospheric ozone depletion Human toxicity

Ecotoxicity

Summer smog Acidification tion

Impact on natural area Extraction of raw materials (for example, mining of coal resources and ore), demands for areas of a certain ecological qual ity (for example, agriculture)

The last step of a life cycle assessment is the analysis and interpretation. This includes the derivation of conclusions and concrete recommendations for action for the planned application or utilization.

The life cycle assessment, as already mentioned, is one of the most thoroughly developed and standardized of the TA methods. Nonetheless, like all methodologies, its also has its weaknesses, blind spots, and deficiencies. Some of these shortcomings need to be mentioned.

1. There are impact categories for which generally accepted impact models do not yet exist. This is particularly true in the relevant categories of human and environmental toxicity. For example, with regard to scale, a consideration of the impact of fine dust particles (the PM-10 risk deals with the potential toxicity of particles smaller than 10 pm) in life cycle impact assessments is therefore already doomed to failure because of its reference to weight and not particle size in nanotechnology applications. Other "qualitative" impacts that cannot be directly correlated with the levels of material and energy flows, such as structural impacts on ecosystems, also cannot adequately be captured.

2. Furthermore, in life cycle assessments, neither the technical risks nor the potency of applications are considered.

In our view, the life cycle assessment alone cannot generate a comprehensive evaluation of the environmental impacts (environmental compatibility) of products and processes (see also Klopfer et al 2007). In addition to the life cycle assessment, a comprehensive environmental assessment plan for nanotechnology applications should - at a minimum - take the following further assessment methodologies into consideration:

• Risk analysis

• Hazard characterization, particularly with the help of technology characterization including analysis of the degree of intervention or intrusion

• (Eco)toxicological analysis

• Environmental impact assessment (particularly with a view to plant facilities)

Using an actuarial approach to risk (risk = occurrence probability x extent of damage), the risk analysis is dependent upon statistical information (alternatively, models). In risk analysis, too, there arise almost insurmountable difficulties with respect to technologies or applications still in development. Statistical data is usually not available. In this situation, it is necessary to fall back on a hazard or risk analysis (hazard characteriza-

tion), as was done in this project, in the form of a general "characterization of nanotechnology."

The analysis of the degree of intervention is part of the technology characterization and looks at the extent to which steering mechanisms or elementary connections are impacted by the possibly extreme potency of a product or process and its potential for expanding space-time impact chains. The concept of "degree of intervention" is intended to establish the nature of a technology, to reflect, for example, the fundamental qualitative differences between the splitting of stone and splitting the atom (cf. von Gleich & Rubik 1996).

The toxicological analysis includes tests for acute toxicity; chronic toxicity; corrosiveness; skin and eye irritation; carcinogenicity, mutagenicity, and reproductive toxicity; skin sensitization (allergic reactions); weakening of the immune system, etc.

Such a set of methods, whose corresponding prioritization must be adapted to the specific application context, should make possible, on the one hand, the assessment of the environmental impacts and risks associated with specific applications as compared to existing applications, and, on the other hand, the analysis of accessible eco-efficiency potentials. However, because information and data for specific application contexts is often lacking and available working resources are limited, the application of this complex method set has significant limitations.

In the project, these methodological shortcomings were minimized through the establishment of priorities in the selection of the specific application contexts. From the entire spectrum of nanotechnological applications, four case studies with anticipatable eco-efficiency potentials were selected on the basis of a preliminary examination and qualitative preliminary assessment. Possible risks and potential dangers of nanotechnology applications - with an emphasis on the toxicity risks associated with nanoparticles - were furthermore analyzed and discussed, and human toxi-cological indications with respect to potentially adverse effects of nanopar-ticles and nanostructured surfaces were recorded. The basis for this were, first, investigations into the impact of ultra-fine particles (UFP) on health, and second, investigations on nanoparticles, but also fullerenes and nano-tubes, which to date have mostly been carried out in experiments with animals. Investigations of possible ecotoxicological effects are still almost non-existent. In addition to the main steps of the analysis, these toxicologi-cal case studies essentially represent an overview of the scientific literature and expert opinions in this field. The discussion on TiO2 nanoparticles is taken as an example.

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