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Water, being dipolar, can be partly aligned by an electric field
and this may be easily shown by the movement of a stream of water
by an electrostatic source . Water is diamagnetic and may be levitated
in very high magnetic fields (10 T, c.f. Earth's magnetic field
30 mT) . Lower magnetic fields (0.2 T) have been shown, in simulations,
to increase the number of monomer water molecules but, rather surprisingly,
they increase the tetrahedrality at the same time. Such fields can
also increase the evaporation rate of water and the dissolution
rate of oxygen but cannot, despite claims by certain expensive water
preparations, increase the amount of oxygen dissolved in water above
its established, and rather low, equilibrium concentration .
Belief in whether or not magnetic or electromagnetic fields can
have any more permanent effect on water, and solutions, depends
on the presence of a working hypothesis for their mode of action
(see also homeopathy). Such hypotheses are emerging.
Water is a more reactive environment when the extent of hydrogen
bonding is reduced . An open, more hydrogen-bonded network structure
slows reactions due to its increased viscosity, reduced diffusivities
and the less active participation of water molecules. Any factors
that reduce hydrogen bonding should encourage reactivity. Water
clusters (even with random arrangements) have equal hydrogen bonding
in all directions. As such, magnetic, electric or electromagnetic
fields that attempt to re-orient the water molecules should necessitate
the breakage of some hydrogen bonds; e.g. electric fields have been
reported to halve the mean water cluster size as measured by 17O-NMR
(see also 'declustered' water). At metallic electrodes, even quite
low voltages can have impressive effects on the orientation of the
water molecules and the positioning of ions . A negative potential
of -0.23 V orients water hydrogen atoms towards the electrode whereas
+0.52 V reverses this; both causing some hydrogen bond breakage
and localized density increase. Ions are attracted or repelled dependent
on their charge.
A high-voltage electric field (333 kV m-1) has been shown to raise
the water activity in bread dough, so ensuring a more efficient
hydration of the gluten . In computer simulations, magnetic fields
may reorient liquid water molecules, weakening and stretching their
hydrogen bonds, but very high field strengths (5x107 V cm-1) are
required to reorient water in ice such that freezing is inhibited
. One of the curious facts, concerning reports of the effects of
magnets and electromagnetic radiation on the properties of water,
is the long lifetime these effects seem to have. This should not
be so surprising, however, as it can take several days for the effects,
of the addition of salts to water, to finally stop oscillating.
In addition to the breakage of hydrogen bonds electromagnetic fields
may perturb in the gas/liquid interface and the produce reactive
oxygen species. The role of dissolved gas in water chemistry may
be more important than commonly realized; particularly if the reported
formation of nano-bubbles containing just a few molecules of gas
is substantiated. Reinforcement of this view comes from out-gassing
experiments that apparently result in the loss of magnetic and electromagnetic
effects . Gas accumulating at hydrophobic surfaces promotes the
hydrophobic effect and low density water formation. The accumulated
gas molecules at such hydrophobic surfaces becomes supersaturating
when this surface low density water is disrupted by electromagnetic
effects. Static magnetic effects have been shown to cause an increase
in the ordered structure of water formed around hydrophobes and
colloids , as shown by the increase in fluorescence of dissolved
probes. This reinforces the view that it is the movement through
a magnetic field, and it associated electromagnetic effect, that
is important for disrupting the hydrogen bonding.
Recently, there has been some debate over 'digital biology'; a proposal
from Jacques Benveniste (leader of the team that produced the controversial
homeopathy paper) that 'specific molecular signals in the audio
range' (hypothetically the 'beat' frequencies of water's infrared
vibrations) may be heard, collected, transmitted (e.g. by phone)
and amplified to similarly affect other water molecules at a receiver
. This unlikely idea is still awaiting independent confirmation
and is thought highly implausible. Rather interestingly, however,
electromagnetic emission has been detected during the freezing of
supercooled water due to the non-equilibrium difference in the electrical
potentials between the solid and liquid phases . It is not unreasonable,
therefore, that similar effects may occur during changes in the
structuring of liquid water. Also, it has been reported that microwave
frequencies can also give rise to signals audible to radar operators
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Unstructured water with fewer hydrogen bonds is a more reactive
environment, as exemplified by the enhanced reactivity of supercritical
water. If electromagnetic effects do indeed influence the degree
of structuring in water, then it is clear that they may have an
effect on health. The biological effects of microwaves, for example,
have generally been analyzed in terms of their very small heating
effects. However, it should be recognized that there may be significant
non-thermal effects due to the imposed re-orientation of water at
the surfaces of biomolecular structures such as membranes. Additionally
as low-frequency, low level alternating electric fields have been
found to affect the electrical conductivity of pure water , the
effects of living near power cables and microwave towers should,
perhaps, not be thought harmless just because no theory for harm
has been formally recognized. Even variations in the geomagnetic
field may have some long term exposure effects.
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