Nano's Troubled Waters:
Latest toxic warning shows nanoparticles cause brain damage in
aquatic species and highlights need for a moratorium on the release of new nanomaterials
A new study revealing that engineered carbon molecules known as "buckyballs"
cause brain damage in fish is one more brick in the wall of evidence suggesting
that manufactured nanoparticles are harmful to the environment and to health.
The results of the study highlight the urgency to heed ETC Group's 2002 call
for a moratorium on manufactured nanoparticles in commercial products and they
back up last month's recommendation by the Institut für ökologische
Wirtschaftforschung - in a report commissioned by the European Parliament -
that nanoparticles should not be released into the environment.(1) Recent scientific
studies have raised serious concerns about the toxicity of nanoparticles (see
"Ten Toxic Warnings," below). This latest study, which has yet to
be published, is the first to simulate what could happen when nanoparticles
are released into the environment.
How many warnings do government regulators require before they take action to
ensure that uses of nanoparticles are safe before workers in production facilities
are harmed and before consumers are further exposed?
At the American Chemical Society's national meeting last week in Anaheim, California,
environmental toxicologist Dr. Eva Oberdörster described what happened
when she exposed nine largemouth bass to water containing buckyballs at concentrations
of 500 parts per billion. (The concentration level is comparable to pollutant
levels commonly found in port waters.) After only 48 hours, the researchers
found "severe" damage to brain tissue in the form of "lipid peroxidation,"
a condition leading to the destruction of cell membranes, which has been linked,
in humans, to illnesses such as Alzheimer's disease. Researchers also found
chemical markers in the liver indicating inflammation, which suggested a full-body
response to the buckyball exposure.(2)
Manufactured nanoparticles, measuring a few billionths of a meter, are already
used in commercial products ranging from anti-aging creams to sunblocks to car
bodies to tennis racquets. Buckyballs - the soccer-ball shaped molecules of
carbon touted as "miracle molecules" because of their unusual chemical
properties - are considered especially promising for applications in drug delivery
and cosmetics as well as fuel cells and solar cells. Buckyballs have not yet
been incorporated into commercial products. The high cost of their manufacture
has been considered the biggest barrier to commercialization, but the price
of a gram of buckyballs is dropping precipitously - from several hundred (US)
dollars to $20 dollars and manufacturers predict the price will drop even further
to 50 cents per gram.(3) It is hard to know how many buckyballs have been manufactured
since their discovery in 1985, but one company in Japan called Frontier Carbon
(a joint venture of Mitsubishi Corporati!
on and Mitsubishi Chemical) is operating a facility with a production capacity
of 40 metric tons per year. The company says it has 300 buyers for its fullerenes
(the chemical family name of buckyballs).(4)
Regarding the results of her buckyball toxicity study, Dr. Oberdörster
warns, "Given the rapid onset of brain damage, it is important to further
test and assess the risks and benefits of this new technology before use becomes
even more widespread." Though it is known that nanoparticles can cross
the blood/brain barrier in humans, it is not yet known whether they will cause
the kind of damage found in Oberdörster's fish.
In a separate experiment, Oberdörster found that buckyballs are also toxic
to "water fleas" - in buckyball-tainted water, half the water flea
population was dead in two days. (According to Oberdörster, that means
buckyballs are "moderately toxic" to water fleas, more toxic than
nickel, but less toxic than copper.[5]) Because water fleas (crustaceans a few
millimeters long) are a food source for other aquatic species, Oberdörster
expressed concern that nanoparticles could begin to accumulate throughout the
food chain, affecting not just fish, but plants and other animals, including
people.(6) Both largemouth bass and water fleas are standard test species for
aquatic toxicity.
Though the market for nanoparticles will approach one billion dollars next year,
neither government regulations nor labeling requirements exist in any country.
Because nanoparticles are composed of elements and compounds whose toxicity
is well-studied at larger scales, they have been assumed safe even though they
can exhibit wildly different properties from their larger siblings.
With regard to her findings, Dr. Oberdörster said that "this is a
yellow light, not a red one."(7) Presumably, she believes that the potential
for safe applications of nanoparticles still exists, but that commercialization
should proceed cautiously until scientific toxicological data catch up to the
technology. ETC Group agrees that a yellow light is in order and, once more,
urges regulators and international policymakers to move swiftly and responsibly
to place a moratorium on the release of new nanoparticles into the environment
until lab protocols can be established and until toxicology studies can be undertaken
and their results verified. Many nano-proponents insist that modifications can
be made to the particles - such as coating them - to ensure that they are safely
biocompatible. While this is theoretically possible, there is no independent
body to assess the modifications nor any regulations to prevent manufacturers
from using unmodified nanoparticles. The situati!
on is made more complicated by most manufacturers' unwillingness to share their
own safety studies with the public or with competitors.
Close-to-market applications for nanoparticles are wide-ranging and many involve
the release of nanoparticles in water or in soil. One company, Altair Nanotechnologies,
currently seeks to market a nanoparticle-based product that will be used to
clean water at industrial fish farms and in swimming pools. Clear Spring Foods,
an aquaculture company that farms around a third of US trout production, has
been carrying out tests for nanoparticle-based vaccine delivery. The DNA vaccine
in nanoparticle form would be added to fish ponds and then activated by ultrasound
to inoculate trout. Meanwhile, reports from Kyoto in Japan show that scientists
are experimenting with using buckyballs for agricultural fertilizer. Fertilizer
runoff is already a major pollutant of water ways.
The international community must formulate a legally-binding mechanism to govern
the products of new technologies, based on the Precautionary Principle, one
that addresses their health, socio-economic and environmental implications.
International assessment should be incorporated under a new International Convention
for the Evaluation of New Technologies (ICENT). The issues of nanoparticle toxicity
and environmental release should be on the radar screens of civil society and
peoples' organizations, as well as intergovernmental agencies. ETC Group has
been in touch with the International Collective in Support of Fishworkers (ICSF,
Chennai, India), which monitors issues related to the livelihood of small-scale
fishworkers around the world. ICSF is already monitoring the issue of nanoparticle
toxicity. ETC Group has also contacted the World Fish Center based in Penang,
Malaysia, which is part of the international network of research centers known
as CGIAR (Consultative Group!
on International Agricultural Research). The issue of nanoparticle toxicity
should be urgently considered by the Oslo Paris Convention for the Protection
of the Marine Environment of the North-East Atlantic (OSPAR), whose Hazardous
Substances Committee meets next month in Wismar, Germany.
The following list is not exhaustive, but includes some of the biggest, reddest
flags on the issue of engineered nanoparticle safety:
Ten Toxic Warnings
1. 1997 - Titanium dioxide/zinc oxide nanoparticles from sunscreen are found
to cause free radicals in skin cells, damaging DNA. (Oxford University and Montreal
University) Dunford, Salinaro et al.(8)
2. March 2002 - Researchers from the Center for Biological and Environmental
Nanotechnology (CBEN, Rice University, Houston) report to US EPA that engineered
nanoparticles accumulate in the organs of lab animals and are taken up by cells.
"We know that nanomaterials have been taken up by cells. That sets off
alarms. If bacteria can take them up then we have an entry point for nanomaterials
into the food chain." - Dr. Mark Wiesner(9)
3. March 2003 - Researchers from NASA/Johnson Space Center report that studies
on effects of nanotubes on the lungs of rats produced more toxic response than
quartz dust. Scientists from DuPont Haskell laboratory present varying but still
worrying findings on nanotube toxicity. "The message is clear. People should
take precautions. Nanotubes can be highly toxic." - Dr. Robert Hunter (NASA
researcher)(10)
4. March 2003 - ETC group publishes first scientific literature survey on nanoparticle
toxicity by toxicopathologist Vyvyan Howard. Dr. Howard concludes that the smaller
the particle, the higher its likely toxicity and that nanoparticles have various
routes into the body and across membranes such as the blood brain barrier. "Full
hazard assessments should be performed to establish the safety of species of
particle before manufacturing is licensed. We are dealing with a potentially
hazardous process." - Dr. Vyvyan Howard(11)
5. July 2003 - Nature reports on work by CBEN scientist Mason Tomson that shows
buckyballs can travel unhindered through the soil. "Unpublished studies
by the team show that the nanoparticles could easily be absorbed by earthworms,
possibly allowing them to move up the food-chain and reach humans" - Dr.
Vicki Colvin, the Center's director(12)
6. January 2004 - Research by Dr. Günter Oberdörster is published
showing that nanoparticles are able to move easily from the nasal passageway
to the brain. "The nanotechnology revolution may design particles that
are very different chemically from the ones we are exposed to, and they might
have very different properties that made them more harmful. We should be vigilant."
- Professor Ken Donaldson, University of Edinburgh(13)
7. January 2004 - Nanosafety researchers from University of Leuven, Belgium,
write in Nature that nanoparticles will require new toxicity tests: "We
consider that producers of nanomaterials have a duty to provide relevant toxicity
test results for any new material, according to prevailing international guidelines
on risk assessment. Even some 'old' chemical agents may need to be reassessed
if their physical state is substantially different from that which existed when
they were assessed initially."- Peter H. M. Hoet, Abderrrahim Nemmar and
Benoit Nemery, University of Belgium(14)
8. January 2004 - At the first scientific conference on nanotoxicity, Nanotox
2004, Dr. Vyvyan Howard presents initial findings that gold nanoparticles can
move across the placenta from mother to fetus.(15)
9. February 2004 - Scientists at University of California, San Diego discover
that cadmium selenide nanoparticles (quantum dots) can break down in the human
body potentially causing cadmium poisoning. "This is probably something
the [research] community doesn't want to hear." - Mike Sailor, UC San Diego.(16)
10. March 2004 - Dr. Eva Oberdörster reports to American Chemical Society
meeting that buckyballs cause brain damage in juvenile fish along with changes
in gene function. They also are toxic to small crustaceans (water fleas). "Given
the rapid onset of brain damage, it is important to further test and assess
the risks and benefits of this new technology before use becomes even more widespread."
- Dr. Eva Oberdörster.(17)
Endnotes:
(1) Haum, Petschow, Steinfeldt, Nanotechnology and Regulation within the framework
of the Precautionary Principle. Final Report for ITRE Committeee of the European
Parliament. Institut für ökologische Wirstschaftforschung (IÖW)
gGmbH, Berlin, 11 February 2004. ETC Group's call for a moratorium on nanotechnology
consists of a temporary cessation of lab research and commercialization of new
products until national governments, in conjunction with their scientific community,
can establish a reviewable "best practices" protocol.
(2) Mark T. Sampson, "Type of buckyball shown to cause brain damage in
fish," Eurekalert, March 28, 2004. Available on the Internet, www.eurekalert.org
(3) Scott Kirsner, "Nanotech, biotech at key juncture," The Boston
Globe, March 22, 2004.
(4) Matt Kelly, "Fullerenes Flourish, and Nano-C can make them by the ton,"
Small Times, 27 October 2003. Available on the Internet, www.smalltimes.com
(5) Rick Weiss, "Nanoparticles Toxic in Aquatic Habitat, Study Finds,"
March 29, 2004.
(6) Mark T. Sampson, "Type of buckyball shown to cause brain damage in
fish," Eurekalert, March 28, 2004. Available on the Internet, www.eurekalert.org
(7) Barnaby J. Feder, "Health Concerns in Nanotechnology," The New
York Times, March 29, 2004.
(8) Dunford, Salinaro et al. "Chemical oxidation and DNA damage catalysed
by inorganic sunscreen ingredients," FEBS Letters , volume 418, no. 1-2,
24 November 1997, pp. 87-90.
(9) Doug Brown, "Nano litterbugs? Experts See Potential Pollution Problems,"
Small Times March 15, 2002. Available on the Internet, www.smalltimes.com
(10) Jenny Hogan, "How safe is nanotech?" Special Report on Nano Pollution,
New Scientist, Vol. 177, No. 2388, 29 March 2003, p. 14.
(11) ETC Group, "Size Matters! The Case for a Global Moratorium,"
Occasional Paper Series, Volume 7, no. 1, April 2003. Available on the Internet,
www.etcgroup.org
(12) Geoff Brumfiel, "A Little Knowledge...," Nature, Vol. 424, no.
6946, 17 July 2003, p. 246.
(13) Alex Kirby, "Tiny Particles Threaten Brain," BBC News Online,
8 January, 2004. Available on the Internet, http://news.bbc.co.uk/1/hi/sci/tech/3379759.stm
(14) Peter Hoet, Abderrahim Nemmar and Benoit Nemery, "Health Impact of
Nanomaterials?" Nature Biotechnology, Vol. 22, no.1, January 2004, p. 19.
(15) Ben Wootliff, ""Bristish Scientist: Nanoparticles Might Move
from Mom to Fetus," Small Times, 14 January 2004. Available on the Internet,
www.smalltimes.com
(16) Justin Mullins, "Safety concerns over injectable quantum dots, New
Scientist, Vol. 181, No. 2436 , 28 February 2004, p. 10.
(17) Mark T. Sampson, "Type of buckyball shown to cause brain damage in
fish," Eurekalert, March 28, 2004. Available on the Internet, www.eurekalert.org