In the construction industry and in architecture, nanotechnology and nanomaterials provide new opportunities. “Nano-products” for construction purposes are currently found in four main sectors: cement-bound construction materials, noise reduction and thermal insulation or temperature regulation, surface coatings to improve the functionalities of various materials, and fire protection. At the present time, nanomaterials – and therefore “nano-products” – remain considerably more expensive than conventional alternatives due to the required production technology, and the technical performance of many products remains to be demonstrated. Both industry workers as well as end users can come into contact with nanomaterials when using a “nano-construction material” and need to be protected from potential health hazards. Information on which nanomaterial is found in which form and concentration in a product is often unavailable, particularly to end users. Once a nanomaterial is solidly embedded in a matrix, for example in concrete or in insulation material, then the probability of exposure is very low or non-existent according to current knowledge, as long as the product is not destructively worked or processed. When workers spray a nano-surface layer or mix mortar at a construction site, for example, they are subject to a potential health hazard by inhaling the dust or tiny droplets of liquid (aerosols). As “nano-construction products” currently play a subordinate role on the market, the current environmental threat due to nanomaterials appears to be low. Nonetheless, virtually no data are available on exposure, so that no comprehensive risk assessment can currently be undertaken for any nanomaterial.

Nanotechnologie und Nanomaterialien bieten auch im Bereich der Bauwirtschaft und der Architektur neue Möglichkeiten. „Nano-Produkte“ für das Bauwesen finden sich derzeit vor allem in vier Bereichen: zementgebundene Baustoffe, Lärm- und Wärmedämmung bzw. Temperaturregelung, Oberflächenbeschichtungen zur Verbesserung der Funktionalitäten diverser Materialien sowie Brandschutz. Zurzeit sind Nanomaterialien – und folglich „Nano-Produkte“ – aufgrund der erforderlichen Produktionstechnologie noch erheblich teurer als die konventionellen Alternativen und die technische Leistung vieler Produkte muss erst noch nachgewiesen werden. Sowohl ArbeitnehmerInnen wie auch EndanwenderInnen können bei der Verwendung eines „Nano-Bauproduktes“ mit Nanomaterialien in Kontakt kommen und sind vor möglichen gesundheitlichen Gefährdungen zu schützen. Vor allem den EndanwenderInnen fehlt aber oft die Information, welches Nanomaterial sich in welcher Form und Konzentration in einem Produkt befindet. Ist ein Nanomaterial fest in eine Matrix eingebunden, etwa in Beton oder in einem Isoliermaterial, ist die Wahrscheinlichkeit einer Exposition mit dem Nanomaterial nach derzeitigem Kenntnisstand sehr gering oder überhaupt nicht gegeben, soferne das Produkt nicht zerstörend bearbeitet wird. Wird etwa eine Nanobeschichtung aufgesprüht oder Mörtel auf einer Baustelle angerührt, bestehen für ArbeiterInnen mögliche Gesundheitsgefährdungen durch das Einatmen von Staub oder kleinsten Flüssigkeitströpfchen (Aerosole). Da derzeit „Nano-Bauprodukte“ am Markt noch eine untergeordnete Rolle spielen erscheint eine aktuelle Umweltgefährdung durch Nanomaterialien gering. Es existieren allerdings kaum Daten zur Exposition, daher kann derzeit für kein Nanomaterial eine umfassende Risikobewertung vorgenommen werden.

The funds for research on nanotechnologies (NMP – nanotechnology and nanosciences, new materials and new production processes), a funding priority established in 2002 by the EU Commission, were increased in the current 7th Framework Program. The expenditures for research on the environmental and health impacts of nanoparticles have shown a particularly large jump. Beyond increasing the budget for additional research projects, the funding structure was also improved. The Commission is pursuing two main goals. The first is to create synergies and help avoid redundancies on the national level by more strongly interlinking the scientific institutions. The second is to intensify the information exchange between the respective institutions by establishing international networks and communication platforms. EU institutions such as the Joint Research Centre are also substantially involved in these networks. One such network is the NanoSafety Cluster, which to date has encompassed more than thirty EHS projects (five of them still from the 6thFramework Programme). In the past, the research focus was mostly on the potential health impacts of synthetic nanomaterials; increasingly, efforts are being made to study the potential impacts on the environment and the protection of employees that produce and process nano-components. Finally, the funding of research proposals that deal with the necessary implementation of regulatory approaches (laboratory analytics, detection methodologies, development and adaptation of measuring instruments) was intensified.

Kennzeichnung ist ein zentrales Steuerungsinstrument in der Risikoregulierung. In der Regel werden damit unterschiedliche Ziele verfolgt: Einerseits sollen Kennzeichnungen den VerbraucherInnen mündige Kaufentscheidungen ermöglichen und sie vor irreführender Information schützen; andererseits sollen sie innovative Produktentwicklung ermöglichen und fördern. KonsumentInnen werden damit in das Risikomanagement verschiedener Produktgruppen mit einbezogen. Die Kennzeichnung nanomaterialhaltiger Produkte war von Anfang an Bestandteil des Nanoregulierungsdiskurses sowohl auf nationaler als auch auf EU-Ebene. Während die Mitgliedstaaten auf nationale Alleingänge bislang verzichteten, finden nanospezifische Kennzeichnungspflichten zunehmend Eingang in das EU-Recht, vorerst in den Bereichen Kosmetika, Lebensmittel und Biozidprodukte. Darüber hinausgehende internationale Initiativen zur freiwilligen Kennzeichnung konnten sich bislang nicht am Markt durchsetzen.

Die Mittel des bereits 2002 von der EU-Kommission eingerichteten Förderschwerpunkts zur Erforschung der Nanotechnologien eingerichtet (NMP – Nanotechnologie und -wissen-schaften, neue Materialien und neue Produktionsprozesse) wurden im derzeit laufenden 7. Rahmenprogramm aufgestockt. Besonders stark gewachsen sind Aufwendungen für die Er-forschung von Umwelt- und Gesundheitsauswirkungen von Nanopartikeln (NP). Es gab nicht nur Budgetmittel für zusätzliche Forschungsprojekte, auch die Förderstrukturen wurden ver-bessert. Die Kommission verfolgt im Wesentlichen zwei Ziele. Zum Einen soll eine stärkere Vernetzung der wissenschaftlichen Einrichtungen Synergieeffekte schaffen und Redundanzen auf nationaler Ebene vermeiden helfen. Zum Anderen soll durch die Einrichtung von interna-tionalen Foren und Kommunikationsplattformen der Wissensaustausch zwischen den befass-ten Institutionen intensiviert werden. An diesen Netzwerken sind auch EU-Einrichtungen wie das Joint Research Centre maßgeblich eingebunden. Ein solches Netzwerk stellt der Nanosa-fety-Cluster dar, in dem bisher mehr als dreissig EHS-Projekte (davon noch fünf aus dem 6. Rahmenprogramm) zusammengefasst sind. In der Vergangenheit wurden vor allem mögliche gesundheitliche Auswirkungen synthetischer Nanomaterialien erforscht; zunehmend werden auch potentielle Schädigungen der Umwelt und der Schutz der Beschäftigten bei der Herstel-lung und Verarbeitung von Nano-Komponenten untersucht. Außerdem werden auch For-schungsvorhaben, die sich mit Fragestellungen zur notwendigen Durchsetzung von Regulie-rungsansätzen beschäftigen (Laboranalytik, Nachweisverfahren, Entwicklung und Anpassung von Messgeräten) verstärkt gefördert.

There is currently no clear evidence that engineered nanoparticles (ENPs) pose a significant threat to the environment. Nonetheless, major gaps in our knowledge exist:
Environmental analytics: Suitable methods to determine nanoparticle concentrations and properties in complex environmental media such as water, soil, sediment or sewage sludge, as well as in organisms, remain to be developed.
Fate and behavior in natural environmental compartments: The special properties of artificial nanomaterials complicate predictions. The current dearth of data is a major stumbling block in comprehensively assessing the fate and behavior of nanomaterials in the environment.
Ecotoxicology: Research is concentrated primarily on controlled laboratory studies using cell cultures or model organisms. One of the major critiques here is the use of unrealistically high doses. No detailed ecotoxicological studies are available that can explain the mechanisms of uptake, distribution, metabolization and excretion of nanoparticles.
Environmental exposure: The most probable entry pathways of nanomaterials into the environment are via sewage water and wastes, but to date no quantitative exposure data are available for nanoparticles. The available studies are based exclusively on model calculations and estimates, which considerably hampers comprehensive risk assessment.
Overall, no definitive conclusions can be drawn on whether environmental damage can be expected or not.

Nanotechnology products, processes and applications have the potential to make important contributions to environmental and climate protection by helping save raw materials, energy and water as well as by reducing greenhouse gases and problematic wastes. Nanomaterials, for example, can increase the durability of materials; dirt- and water-repellant coatings are designed to help reduce cleaning efforts; novel insulating materials can improve the energy efficiency of buildings; adding nanoparticles to reduce the weight of materials can help save energy during transport. Great hopes are being placed on nano-technologically optimized products and processes that are currently under development in the energy production and storage sectors.
Emphasis is often placed on the sustainable potential of nanotechnology, but this in fact represents a poorly documented expectation. Determining a product’s actual effect on the environment – both positive and negative – requires considering the entire life cycle from the production of the base materials to disposal at the end of its useful life. Only few life cycle analyses have been conducted, but some show clearly reduced environmental impacts or energy and resource savings for certain products that use nanomaterials or nanotechnology processes. Nonetheless, not every “nano-product” is a priori environmentally friendly or sustainable, and the production of nanomaterials often requires large amounts of energy, water and environmentally problematic chemicals.

As far as concerns the risks of nanotechnology, the focus of attention is on nanomaterials and in particular on free nanoparticles. Alongside the investigation of their possible toxicity, the question of the exposure of humans and the environment is an essential element of their risk assessment. Nanoparticles suspended (distributed and embedded) freely in the air are of particular relevance, since they can easily penetrate the human body via the lungs. In addition, it is extremely difficult to monitor the spread of nanoparticles in the air.
Commercially available particle counters can be used to determine the concentration of particles and droplets in the air down to a size of a few nanometres. In the light of the high background concentration of natural nanoparticles and those generated by human activity, the first priority is to distinguish between natural and synthetic nanoparticles. While an on-site concentration measurement can be carried out in a few minutes, the analysis of the nanoparticles contained in the air, that is the determination of their form and composition is only possible using complex electron microscopy procedures in the laboratory. This situation currently constitutes the main problem for determining the concentration of synthetic nanoparticles and will do so for the near future.

Carbon nanotubes (CNTs) can be inhaled and thus deposited in the lungs. Studies have shown that specific CNTs, namely those that are long (10-20 µm), thin (5-10nm), needle-shaped and non-soluble (biopersistent), can promote the formation of lung diseases and show behaviour similar to that of asbestos fibres. Short or long fibres that are not needle-shaped will not, however, induce inflammatory changes, no more than a single carbon particle would. Comprehensive life-cycle analyses regarding the potential environmental benefits arising from the use of CNTs (such as resource savings owing to more light-weight materials) are not available to date. At present, the production of CNTs still requires a high energy input, which offsets any potential environmental benefits. Their high reactivity and ability to transport other substances raises concerns about a possible ecotoxicity of CNTs. The data available are still restricted in scope, and the discussion of results is controversial. Given the lack of reliable data on exposure, an adequate assessment of health and/or environmental risks is not possible for the time being.
At present, specific regulations for CNTs or other nanomaterials exist neither in the laws governing chemicals nor in regulations for occupational health and safety. Hence, the relevant authorities recommend that the precautionary principle should be applied and measures taken to avoid exposure or keep it as low as possible.