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Ed Jewett
09-21-2011, 04:29 AM
Nanoparticles Cause Brain Injury in Fish (http://cryptogon.com/?p=24973)September 21st, 2011Via: Science Daily (http://www.sciencedaily.com/releases/2011/09/110919074256.htm):
Scientists at the University of Plymouth have shown, for the first time in an animal, that nanoparticles have a detrimental effect on the brain and other parts of the central nervous system.
They subjected rainbow trout to titanium oxide nanoparticles which are widely used as a whitening agent in many products including paints, some personal care products, and with applications being considered for the food industry. They found that the particles caused vacuoles (holes) to form in parts of the brain and for nerve cells in the brain to die. Although some effects of nanoparticles have been shown previously in cell cultures and other in vitro systems this is the first time it has been confirmed in a live vertebrate.
The results will be presented at the “6th International meeting on the Environmental Effects on Nanoparticles and Nanomaterials” (21st — 23rd September) at the Royal Society in London.
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Peter Lemkin
09-21-2011, 05:54 AM
This is a little known problem, outside of a small group of Environmental research scientists. The use of nanoparticles is growing rapidly. They have both nominally good and bad uses in nearly all branches of science and applied technology. Most are not intended to wind up in the general environment, but do - as with other environmental pollution. Others are intentionally put into the environment, without much thought about the ecosystem and longterm effects - having been designed for a specific purpose - usually an immediate 'fix'. Many of these nanoparticles have now found to be toxic to some or all life forms. There are some scientists and several universities now concentrating on quantifying the effects and the mechanisms. Generally, the particles are too small for the normal clearance mechanisms in the organisms to function properly. In other cases, the nanoparticles are too 'active' chemically [for example nanosilver] to be 'handled' by the organism's biochemical defenses - they are also novel and organisms have had zero time to adapt to them, evolutionarily. They are a growing problem and rapidly causing a growingly disproportionate part of toxic environmental substances. :mexican: :joystick: Humans are their own worst enemy...if only more would realize it and adopt a more 'natural' approach to how we proceed. Nanoparticles are something you'll hear a lot about in the future, mostly in the negative sense. Most are not aware how pervasive they now are and are quickly becoming. Have any 'odor-eating' shoes or clothes..they contain nanosilver. Etc. Often hundreds of tons of nanoparticles, often toxic, are dumped into the environment for various reasons - or find their way into the environment through the waste streams. A serious and growing problem....the very small making a very BIG problem!!!!!!!

Peter Lemkin
09-21-2011, 06:07 AM
Ten things you should know about nanotechnology

9) The risk factor
(http://www.nanowerk.com/nanotechnology/ten_things_you_should_know_9.php)
It has become quite a familiar pattern for regular readers of nanoscience and nanotechnology literature: on some days you see articles that slam certain nanomaterials, and nanotechnology in general, as inherently risky due to a new scientific paper that reports alarming levels of toxicity of a particular nanoparticle. On other days you find research papers that report no apparent risk whatsoever with the same nanomaterials. These reports then get cherry-picked by various interest groups to fit their agendas – the cosmetics industry for instance claims their products and the nanoparticles in them are perfectly safe; environmental groups contend that nanomaterials are inherently risky and that rigorous testing is needed before large scale commercialization of nanoproducts can happen; some even call for a complete moratorium on nanomaterial production.
The result is a situation that is confusing as hell not only for laypersons but also for industry, researchers and the journalists who cover the field. Fact is, that every new technology is inherently risky – plenty of people are being injured or killed every year by electricity, cars, chemicals, or nuclear energy, just to name a few. In order to reap the benefits of a new technology and make it acceptable to society there has to be a general perception that the risks are fully understood, can be managed and it is clear who is responsible for what. All of that is currently missing in nanotechnology.
Although the speed and scope of nanotechnology risk research – and the emerging field of nanotoxicology – is picking up, a lot of this work is stand-alone research that is not being coordinated within a larger framework (read: Nanotechnology risk assessment could benefit from nanoparticle categorization framework").
In order to discuss the risks of nanotechnology, we need to take a closer look at these nanostructures. The mere presence of nanomaterials is not in itself a threat; as a matter of fact, nanoparticles exist in nature. It is only certain aspects that can make them risky, in particular their mobility and their increased reactivity. Only if certain properties of certain nanoparticles were proven harmful to living beings or the environment would we be faced with a genuine hazard.
Natural and Anthropogenic Sources of Nanoparticles (<100nm)

Potential for release and exposure to nanoscale substances (Source: Oberdörster; Reproduced with permission from Environmental Health Perspectives)
In addressing the health and environmental impact of nanotechnology we need to differentiate two types of nanostructures:
1) Nanocomposites, nanostructured surfaces and nanocomponents (electronic, optical, sensors etc.), where nanoscale particles are incorporated into a substance, material or device (“fixed” nano-particles); and
2) “free” nanoparticles, where at some stage in production or use individual nanoparticles of a substance are present. These free nanoparticles could be nanoscale species of elements, or simple compounds, but also complex compounds where for instance a nanoparticle of a particular element is coated with another substance.
There seems to be consensus that, although one should be aware of materials containing fixed nanoparticles, the immediate concern is with free nanoparticles.

The extraordinarily high numbers of nanoparticles per given mass will likely be of toxicological significance when these particles interact with cells and subcellular components. Likewise, their increased surface area per unit mass can be toxicologically important. (Source: Source: G. Oberdörster et al.: "Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine Particles" Environmental Health Perspectives Volume 113, Number 7, July 2005. Reproduced with permission from Environm. Health Persp.)
Because nanoparticles are very different from their everyday counterparts – thanks to surface and quantum effects – their adverse effects cannot be derived from the known toxicity of the macro-sized material. This poses significant issues for addressing the health and environmental impact of free nanoparticles.
To complicate things further, in talking about nanoparticles it is important that a powder or liquid containing nanoparticles is almost never monodisperse, but will contain a range of particle sizes. This complicates the experimental analysis as larger nanoparticles might have different properties than smaller ones. Also, nanoparticles show a tendency to aggregate and such aggregates often behave differently from individual nanoparticles.
Potential for release and exposure to nanoscale substances

(Source: Joyce S. Tsuji: "Research Strategies for Safety Evaluation of Nanomaterials, Part IV: Risk Assessment of Nanoparticles")
Health Issues
There are four entry routes for nanoparticles into the body: they can be inhaled, swallowed, absorbed through skin or be deliberately injected during medical procedures. Once within the body they are highly mobile and in some instances can even cross the blood-brain barrier. How these nanoparticles behave inside the organism is one of the big issues that need to be resolved. Basically, the behavior of nanoparticles is a function of their size, shape and surface reactivity with the surrounding tissue. They could cause “overload” on phagocytes, cells that ingest and destroy foreign matter, thereby triggering stress reactions that lead to inflammation and weaken the body’s defense against other pathogens. Apart from what happens if non- or slowly degradable nanoparticles accumulate in organs, another concern is their potential interaction with biological processes inside the body: because of their large surface, nanoparticles on exposure to tissue and fluids will immediately absorb onto their surface some of the macromolecules they encounter. Can this, for instance, affect the regulatory mechanisms of enzymes and other proteins?
Environmental Issues
Not enough data exists to know for sure if nanoparticles could have undesirable effects on the environment. Two areas are relevant here:
1) In free form nanoparticles can be released in the air or water during production (or production accidents) or as waste byproduct of production, and ultimately accumulate in the soil, water or plant life.
2) In fixed form, where they are part of a manufactured substance or product, they will ultimately have to be recycled or disposed of as waste. We don’t know yet if certain nanoparticles will constitute a completely new class of non-biodegradable pollutant. In case they do, we also don’t know yet how such pollutants could be removed from air or water because most traditional filters are not suitable for such tasks (their pores are too big to catch nanoparticles).
To properly assess the health hazards of engineered nano-particles the whole life cycle of these particles needs to be evaluated, including their fabrication, storage and distribution, application and potential abuse, and disposal. The impact on humans or the environment may vary at different stages of the life cycle.
One term you hear quite often in discussion about the potential risks of nanotechnology is precautionary principle. This moral and political principle, as commonly defined, states that if an action or policy might cause severe or irreversible harm to the public or to the environment, in the absence of a scientific consensus that harm would not ensue, the burden of proof falls on those who would advocate taking the action. The principle aims to provide guidance for protecting public health and the environment in the face of uncertain risks, stating that the absence of full scientific certainty shall not be used as a reason to postpone measures where there is a risk of serious or irreversible harm to public health or the environment.
In contrast to the U.S., much of the science and technology policy in Europe is guided by the Precautionary Principle (see:"Late lessons from early warnings for nanotechnology"), although critics argue that this contributes to the high level of bureaucracy and red tape that prevents European companies from speedily translating the continent's leading-edge nanotechnology research into commercial products.

Ed Jewett
09-23-2011, 01:33 AM
RNA from Rice Can Survive Digestion and Alter Gene Expression (http://cryptogon.com/?p=25038)September 22nd, 2011Via: Discover (http://blogs.discovermagazine.com/80beats/2011/09/21/what-you-eat-affects-your-genes-rna-from-rice-can-survive-digestion-and-alter-gene-expression/):
It’s no secret that having lunch messes with your biochemistry. Once that sandwich hits your stomach, genes related to digestion have been activated and are causing the production of the many molecules that help break food down. But a new study suggests that the connection between your food’s biochemistry and your own may be more intimate than we thought. Tiny RNAs usually found plants have been discovered circulating in blood, and animal studies indicate that they are directly manipulating the expression of genes.
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