Kreuger (1976) reported that in laboratory animals serotonin, a powerful neurohormone, could be affected by the polarity and concentration of air ions breathed. Serotonin can produce neurovascular, endocrinal, and metabolic effects throughout the body (Kreuger 1976) and plays an important role in mood and sleep patterns. Negative ions act to reduce serotonin levels in the respiratory system, blood and brain, whilst positive ions increased serotonin levels. Hawkins (1985) reports that his own work confirmed these effects. High concentrations of serotonin have been associated with migraine headache attacks. Thus an increase in negative ions would be expected to reduce migraine attacks. Reduced serotonin levels result in a mentally relaxed state and reduction in feelings of depression. Sulman et al have reported that individuals suffering Sharav wind sensitivity have been successfully treated by inhalation of air containing excess negative ions, or by administration of serotonin blocking drugs (Kreuger 1976).The situation is confused, however, by other factors. Negative ions appear to reduce serotonin via enhancement of monoamine oxidase activity. Paradoxically, mental illness is often successfully treated using drugs which inhibit this activity and cause a rise in serotonin levels in the brain.
Kreuger A P, Reed E J. Biological impact of small air ions. Science, 193, 1209-13. 1976
Hawkins LH. Biological significance of air ions. Proc. IEE Colloquium on ions in the atmosphere, natural and man made. London, UK, 1985. BLL Conf Ind. 3315.470 No 88 1985.
The consensus of the literature reviewed is that environmental air ion concentration levels and balance can affect a wide range of biological organisms, including humans. Elevated negative air ion levels are widely reported to have beneficial effects on humans including enhanced feeling of relaxation, and reduced tiredness, stress levels, irritability, depression, and tenseness. Depleted ion levels and enhanced positive ion levels are reported to have no effect, or deleterious effects. The body voltage of the subject is likely to play an important role in affecting the ingestion of ions. In an environment of balanced air ion levels, the balance of ingested ions may be heavily influenced by a high body voltage. High positive body voltage would be expected to reduce positive ion ingestion and increase negative ion ingestion. High negative body voltage would be expected to reduce negative ion ingestion and increase positive ion ingestion. These effects are expected to be ameliorated by maintaining the body potential near zero.
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Side effects from positive ions winds (such as the Chinook wind in Calgary and the Santa Ana winds in southern California) compiled by a Swiss meteorological report in 1974 are as follows:
Physical side effects: Body pains, sick headaches, dizziness, twitching of the eyes, nausea, fatigue, faintness, disorders in saline (salt) budget with fluctuations in electrolytical metabolism (calcium and magnesium; critical for alcoholics), water accumulation, respiratory difficulties, allergies, asthma, heart and circulatory disorders (heart attacks approx. 50% higher) low blood pressure, slowing down in reaction time, more sensitivity to pain, inflammations, bleeding embolisms of the lungs, and thrombosis.
Psychological side effects: emotional imbalance, irritation, vital disinclination, compulsion to meditate, exhaustion, apathy, disinclination or listlessness toward work (poor school achievement), insecurity, anxiety, depression (especially after age forty to fifty); rate of attempted suicide about 20% higher, larger number of admittance's to clinics in drug cases.