Researcher Claims Magnets Can Affect Blood Viscosity 175
BuzzSkyline writes "A few minutes in a high magnetic field (1.3 Tesla) is enough to thin blood by 30%, potentially leading to a new drug-free therapy to prevent heart attacks. The powerful field causes blood cells to line up in chains that flow much more easily than randomly-scattered individual cells, according to research scheduled to appear this month in the journal Physical Review E." I can't help thinking of Penn & Teller's look at magnets-as-medicine, though at least the idea here described sounds testable and doesn't rely on the power of suggestion.
strength of magnetic fields for perspective (Score:5, Informative)
Interstellar space 10^-10 Tesla 10^-6 Gauss
Earth's magnetic field 0.00005 Tesla 0.5 Gauss
Small bar magnet 0.01 Tesla 100 Gauss
Within a sunspot 0.15 Tesla 1500 Gauss
Small NIB magnet 0.2 Tesla 2000 Gauss
Big electromagnet 1.5 Tesla 15,000 Gauss
Strong lab magnet 10 Tesla 100,000 Gauss
Surface of neutron star 100,000,000 Tesla 10^12 Gauss
Magstar 100,000,000,000 Tesla 10^15 Gauss
from http://www.coolmagnetman.com/magflux.htm [coolmagnetman.com]
Fundamental misunderstanding of magnetic moments (Score:5, Informative)
These guys should have talked to a biophysicist before they stated talking about this in public. A hemoglobin complex holds 4 individual iron cations, in four pockets that are pretty far apart from each other. On top of that, the whole hemoglobin molecule is tumbling around inside red blood cells, without any physical attachment to the cell membrane or cytoskeleton. The magnetic moment of an iron atom is the net result of its electrons orbiting the nucleus, the orientation of the electron orbitals and the nuclear spin, all of which tumble pretty randomly. You only get macro ferrormagnetic behaviour when a bunch of iron atoms are locked right next to each other in a rigid lattice structure, like a crystal of magnetite.
Even if you could align all the iron magnetic moments in hemoglobin, you probably wouldn't be able to get the hemoglobin to aggregate, it would just tumble a bit differently. You certainly wouldn't have any observable mechanical effect on red blood cells. Red Blood Cells are however very sensitive to mechanical pumps. It you mechanically force them through a relatively small aperture (like you would to measure viscosity), they would probably start to coagulate (clump together) until the pressure let off, in which case they would fall apart again.
Since they stored the blood in the fridge for some time and didn't end up with one giant ball of clot, they obviously had an anticoagulant mixed in too, which would impact what they observed (namely that the cells fell apart again some time after they stopped pumping).
Talk to a biophysicist next time guys!
Re:subtle issues (Score:5, Informative)
Back to TFA - only an abstract is posted, so I can't read about the proposed mechanism, but as all the people who work with MRI's have pointed out this amount of effect on blood viscosity at such a "low" field strength is hard to imagine unless there is something unusual about the shape or duration of the pulse that makes it substantially different from the static field in an MRI. Previous work with static fields has shown maybe a 1% change at 1T field strengths, with the more significant, 15-20% changes not evident until 5T or so (which is much higher than a typical clinical-use MRI, although some research MRIs certainly are in this range)
see fig 5 of this article if you have institutional access for the work cited above http://www.sciencedirect.com/science/article/pii/S030488530001249X [sciencedirect.com]
similarly, the WHO summary of health effects of exposure to magnetic fields only cautions against cardiovascular effects for fields > 8T http://www.who.int/mediacentre/factsheets/fs299/en/index.html [who.int]
Re:subtle issues (Score:4, Informative)
That's because you are moving. Per Maxwell's laws changing magnetic fields induce a current. If you move your head too quickly through them those tiny currents can be induced in your inner ear resulting in the nausea.
I work in the MRI field on the engineering research side of things. Those sounds a lot like MRI scanners. The 7T scanners are notoriousness for inducing nausea when moving in and out of them because the field drops off and grows so quickly around the scanner. I've never heard of nausea being induced from a 3T before though. Maybe I just haven't been moving around fast enough inside it.