02/04/2008

Some nanoparticles are harmful to human health

In the light of current research information, it is clear that some
nanoparticles may be harmful for humans, while some would appear to be
harmless. International chemistry companies have begun industrial manufacturing
of synthetic nanoparticles at an increasingly large scale. The number of
exposed workers is rising and environmental hazards may be intensified. In
order to prevent the environmental risks posed by synthetic nanoparticles in
time, significant investments must be made in the study of associated health
hazards.

"So far, no studies have been published that would have explored the direct
effects of synthetic nanoparticles on human beings," states Professor Kai
Savolainen from the Finnish Institute of Occupational Health (FIOH). The
production volumes of nanoparticles have been low and the number of exposed
workers has been small. "The fact that no health effects of synthetic
nanoparticles have so far been detected on humans says nothing about the
hazards posed by these particles," stresses Savolainen.

Titanium dioxide used in sun screen lotions causes pneumonia in experimental
animals

Nano-sized titanium dioxide is known to be harmful to lungs and cause pneumonia
in experimental animal models, even though larger particles of titanium dioxide
do not have this effect. As titanium dioxide particles are used for instance in
sunscreen lotions, exposure to nanoparticles may occur in their manufacturing.
The same particles are currently being developed for use in car tires.

As the use of synthetic nanoparticles continues to expand, exposure becomes an
issue at least in the cosmetics and textile industries, chemical industry, car
construction, manufacturing of electronic appliances as well as in the
manufacturing of mobile phones and other wireless communication devices.
Advances in the capacity of computers are based on the developments of
nanotechnology.

In the future, significant exposure may occur in smaller enterprises that
utilize nanotechnology but do not have their own research laboratories or the
opportunity to hire staff with competence in the field. The responsibility to
protect staff members is especially notable with research institutes studying
nanotechnology.

Nanoparticles can enter the brain

The entry of synthetic nanoparticles into the brain via the nerve fibers for
smell is entirely possible. The effects of nanoparticles on the brain are
unknown. In aerosol form, nanoparticles may also be explosive and as such
dangerous for humans even outside of the body.

REACH legislation requires study on the safety of nanotechnology
EU's new chemicals legislation REACH applies to substances that are
manufactured in amounts exceeding one ton a year. REACH requires that prior to
their entry into the market, the safety of nanoparticles, too, must be studied
with both experimental animal and cell studies if the overall annual production
volume exceeds one ton. A plant is currently under construction in Europe that
will manufacture 200 tons of synthetic carbon nanofibres a year, and in a
couple of years the production volume will be increased to 3,000 tons a year.

Prompt action in the current situation could enable the prevention of the
safety risks of this revolutionary new technology before they have even had
time to emerge. This requires sufficient funding for research on the safety
risks.

Out of all research in nanotechnology, only about one percent targets the use
of health effects and other hazards and about 99% is aimed at developing
nanoparticles and nanotechnologies. Consequently, the gap between the progress
of the technology and safety information is growing rapidly. Professor Ruth
Duncan from the University of Cardiff states that in 2006 nanotechnology was
financed with about 8.6 billion euros and the value of the nanoparticle market
is expected to rise to 2.1 trillion euros by 2014.

Study of health effects requires new measuring equipment and methods
Research on the safety of nanotechnology needs easy to use and portable
measuring equipment as well as reference materials and standards required by
research and product development. Measuring equipment must be developed so that
the concentrations involved with the exposure can be measured. Without
measurement data, reliable assessment of health risks is not possible and we
are forced to work with assumptions. Current research methods are not
necessarily suitable for the study of synthetic nanoparticles, because the
nature and properties of a substance change at the nano level.

There are thousands of different nanoparticles

The diameter of a nanoparticle is less than 100 nm. One nanometer is one
billionth of a metre or one millionth of a millimeter. "As to their shape,
diameter, and chemical composition, nanoparticles can produce an almost
infinite number of different combinations," concludes Paul Schulte, the leading
researcher in nanotechnology in the United States. This is why it is incorrect
to speak generally of synthetic nanoparticles or nanotechnologies. Establishing
a system that would enable the categorization of nanoparticles according to
their characteristics, impact mechanisms, and effects would facilitate the job
of searchers, manufacturers and authorities."

Finland and FIOH at the forefront of study on the health hazards of
nanotechnology

FIOH has been developing a research programme on the safety and health of
nanotechnology for four years. During this period, FIOH has developed an
operational model to support research on nanoparticles, established research
laboratories to study the health effects of synthetic nanoparticles, and
acquired millions of euros worth of funding from Finland and the EU. In
co-operation with numerous partners operating both in Finland and abroad, the
Finnish Institute of Occupational Health is actively studying exposure to
synthetic nanoparticles, the health hazards of these particles, and their
prevention. There is active co-operation both with research institutes and with
numerous enterprises in the field.

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AplusA-online.de - Source: Finnish Institute of Occupational Health