Hi gang,
The scientists that state "BSE is a food borne disease" need to understand a few concepts.
First, never (EVER) has the brain homogenate been CHARACTERIZED. This means, that the composition (ie: elemental content) of the brain tissue been analyzed. So they don't really know what they are injecting, drenching, or inhaling.
The have, in fact, burned the tissue to temperatures of 600 degress Celcius (thus destroying all PROTEINs) and still been able to "transmit" disease by intracranial injection - demonstrating a reverse concept: "that proteins are NOT the transmissible agent"
Proteins carry metals, some are even called "metallothionines" (excuse spelling if I'm slightly wrong on it)..... Many of these are metal specific carriers.
Another free online paper is very intriguing, because they forced mice to
INHALE nanoparticles that were magnetic, and labelled with a fluorescent marker.
The study demonstrates that even though the 50 nm particles were inhaled,
not alot showed up in the olfactory system, but they did make it to various organs in the body (in larger amounts) including getting past the blood-brain barrier and the blood-testis barrier.
Copper is not a magnetic metal. Manganese and iron are. In fact, manganese is used big-time for magnetic needs. This study used a ferrite compound. Take a look, there are some good pictures of slides showing the fluorescent marked particles in tissues.
Here's the link to this very good data,
http://www.jstage.jst.go.jp/article/joh/50/1/1/_pdf
J Occup Health. 2008 Jan;50(1):1-6.
Body distribution of inhaled fluorescent magnetic nanoparticles in the mice.
Kwon JT, Hwang SK, Jin H, Kim DS, Minai-Tehrani A, Yoon HJ, Choi M, Yoon TJ, Han DY, Kang YW, Yoon BI, Lee JK, Cho MH.
Laboratory of Toxicology, College of Veterinary Medicine, Seoul National University, Seoul, Korea.
Reducing the particle size of materials is an efficient and reliable tool for improving the bioavailability of a gene or drug delivery system. In fact, nanotechnology helps in overcoming the limitations of size and can change the outlook of the world regarding science. However, a potential harmful effect of nanomaterial on workers manufacturing nanoparticles is expected in the workplace and the lack of information regarding body distribution of inhaled nanoparticles may pose serious problem. In this study, we addressed this question by studying the body distribution of inhaled nanoparticles in mice using approximately 50-nm fluorescent magnetic nanoparticles (FMNPs) as a model of nanoparticles through nose-only exposure chamber system developed by our group. Scanning mobility particle sizer (SMPS) analysis revealed that the mice were exposed to FMNPs with a total particle number of 4.89 x 10(5) +/- 2.37 x 10(4)/cm(3) (low concentration) and 9.34 x 10(5) +/- 5.11 x 10(4)/cm(3) (high concentration) for 4 wk (4 h/d, 5 d/wk). The body distribution of FMNPs was examined by magnetic resonance imaging (MRI) and Confocal Laser Scanning Microscope (CLSM) analysis. FMNPs were distributed in various organs, including the liver, testis, spleen, lung and brain. T2-weighted spin-echo MR images showed that FMNPs could penetrate the blood-brain-barrier (BBB). Application of nanotechnologies should not produce adverse effects on human health and the environment. To predict and prevent the potential toxicity of nanomaterials, therefore, extensive studies should be performed under different routes of exposure with different sizes and shapes of nanomaterials.
PMID: 18285638
Their earlier studied, mentioned in the one above is also available free,
however, in this paper
the nanoparticles were coated with silica which would have significantly interferred with the magnetic nanoparticles ability to adhere to proteins. The energy of the particle is related to its size, shape and composition. Depending on these factors, some nanoparticles would be more likely to bind to proteins.
Uranium and tungesten for example, are well-known to bind to DNA. Particles of these metals are often used in genetic modification of plants, etc., as the Monsantos of the world, et al., attach fragments of the new (often transgenetic material) DNA to these metal particles and shoot them into cells using a particle gun accelerator.
The noted researchers only followed the intraperitoneal injected mice (below study) for a period of 4 weeks and declared them non-toxic. Guess that's OK if you don't plan to live for very long!! I found this similar tactic used by the manufacturers of the aluminum-laden Gardasil vaccine (for HPV) where they only followed adverse reactions for 14 days.
If anything, these declarations by science demonstrate the absolute necessity of reading the entire paper to make your own judgement. Abstracts represent the findings that the researchers want to push/ or that would best grab attention.
Toxicol Sci. 2006 Jan;89(1):338-47. Epub 2005 Oct 19. Links
Erratum in:
Toxicol Sci. 2006 Mar;90(1):267.
Toxicity and tissue distribution of magnetic nanoparticles in mice.
Kim JS, Yoon TJ, Yu KN, Kim BG, Park SJ, Kim HW, Lee KH, Park SB, Lee JK, Cho MH.
Laboratory of Toxicology, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea.
The development of technology enables the reduction of material size in science. The use of particle reduction in size from micro to nanoscale not only provides benefits to diverse scientific fields but also poses potential risks to humans and the environment. For the successful application of nanomaterials in bioscience, it is essential to understand the biological fate and potential toxicity of nanoparticles. The aim of this study was to evaluate the biological distribution as well as the potential toxicity of magnetic nanoparticles to enable their diverse applications in life science, such as drug development, protein detection, and gene delivery. We recently synthesized biocompatible silica-overcoated magnetic nanoparticles containing rhodamine B isothiocyanate (RITC) within a silica shell of controllable thickness [MNPs@SiO2(RITC)]. In this study, the MNPs@SiO2(RITC) with 50-nm thickness were used as a model nanomaterial. After intraperitoneal administration of MNPs@SiO2(RITC) for 4 weeks into mice, the nanoparticles were detected in the brain, indicating that such nanosized materials can penetrate blood-brain barrier (BBB) without disturbing its function or producing apparent toxicity. After a 4-week observation, MNPs@SiO2(RITC) was still present in various organs without causing apparent toxicity. Taken together, our results demonstrated that magnetic nanoparticles of 50-nm size did not cause apparent toxicity under the experimental conditions of this study.
PMID: 16237191
Sorry, but the link for this paper wouldn't open up for me today. Do a google search.