Nanotechnology in Food & Agriculture - denix

Nanofoods and nano agriculture pose
new environmental risks
The production, use and disposal of foods,
food packaging and agricultural products
containing manufactured nanomaterials
will inevitably result in the release of these
nanomaterials into the environment.
This may be the result of waste streams
associated with manufacturing, wear
during the product’s use, or following end
of life product disposal or recycling. Other
nanomaterials will be released into the
environment intentionally, for example as
pesticides or plant growth treatments.
Although commercial use of
nanomaterials by the agriculture and
food sectors is increasing, the ecological
risks associated with nanomaterials
remain very poorly understood. Some
aquatic organisms appear to concentrate
manufactured nanomaterials, but
their uptake into plants has not been
studied, and it is unknown whether or not
nanomaterials will accumulate along
the food chain (Boxhall et al. 2007; Tran
et al. 2005). Early studies demonstrating
the potential for nanomaterials now in
commercial use to be environmentally
harmful underscore the urgent need
for further research (Moore 2006). The
environmental risks associated with crops
which have been genetically engineered
using nanomaterials and synthetic biology
organisms being developed for agriculture
are even more poorly understood.
Nanomaterials now in commercial use
pose serious ecological risks
Despite the limited number of studies
examining the ecological effects of
nanomaterials, there is already evidence
suggesting that nanomaterials in
commercial use by the agriculture and
food industry may cause environmental
harm. This is especially true for
antibacterial nanomaterials such as silver,
zinc oxide and titanium dioxide, which
are increasingly being added to food
Friends of
the Earth
packaging and food contact materials
including cling wrap, chopping boards,
cutlery and food storage containers.
Nano titanium dioxide, one of the most
widely used nanomaterials, caused organ
pathologies, biochemical disturbances,
and respiratory distress in rainbow trout
(Federici et al. 2007). Nano titanium
dioxide is also toxic to algae and to water
fleas, especially after exposure to UV light
(Hund-Rinke and Simon 2006; Lovern and
Klaper 2006). Other preliminary studies
have also found that nano zinc is toxic to
algae and to water fleas (Luo 2007) and
that nano zinc oxide is toxic to bacteria
and to water fleas (Heinlaan et al. 2007).
These findings are concerning, especially
as water fleas are used by regulators as
an ecological indicatcor species.
The effects of nanomaterials on
bacteria, microbes and fungi in natural
systems remain very poorly understood.
It is possible that the increased presence
in waste streams of highly potent
antibacterial nanomaterials could disrupt
the functioning of beneficial bacterial in
the wider environment, for example those
performing nitrification and denitrification
in freshwater and the marine environment
(Throback et al. 2007). Nano-antimicrobial
agents could also disrupt the functioning
of nitrogen fixing bacteria associated
with plants (Oberdörster et al. 2005a).
Any significant disruption of nitrification,
denitrification or nitrogen fixing processes
could have negative impacts for
the functioning of entire ecosystems.
There is also a risk that widespread use
of antimicrobials will result in greater
resistance among harmful bacterial
populations (Melhus 2007).
Although not currently in commercial use
by the food industry, carbon nanotubes
have been touted for future use as
antibacterials in food packaging and
food manufacturing (ElAmin 2007c) and
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