Ryushi T. Kita I. Sakurai T. Yasumatsu M. Isokawa M. Aihara Y. Hama K. Institution
Department of Exercise and Sports Science, Faculty of Science, Tokyo Metropolitan University, Japan.
The effect of exposure to negative air ions on the recovery of physiological responses after moderate endurance exercise. Source
International Journal of Biometeorology. 41(3):132-6, 1998 Feb. Abstract
This study examined the effects of negative air ion exposure on the human cardiovascular and endocrine systems during rest and during the recovery period following moderate endurance exercise. Ten healthy adult men were studied in the presence (8,000-10,000 cm-3) or absence (200-400 cm-3) of negative air ions (25 degrees C, 50%
humidity) after 1 h of exercise. The level of exercise was adjusted to represent a 50-60% load compared with the subjects' maximal oxygen uptake, which was determined using a bicycle ergometer in an unmodified environment (22-23 degrees C, 30-35% humidity, 200-400 negative air ions.cm-3). The diastolic blood pressure (DBP) values during the recovery period were significantly lower in the presence of negative ions than in their absence. The plasma levels of serotonin (5-HT) and dopamine (DA) were significantly lower in the presence of negative ions than in their absence. These results demonstrated that exposure to negative air ions produced a slow recovery of DBP and decreases in the levels of 5-HT and DA in the recovery period after moderate endurance exercise. 5-HT is thought to have contributed to the slow recovery of DBP.
Watanabe I. Noro H. Ohtsuka Y. Mano Y. Agishi Y. Institution
Department of Rehabilitation and Physical Medicine, Hokkaido University School of Medicine, Sapporo City, Japan. Title
Physical effects of negative air ions in a wet sauna.
International Journal of Biometeorology. 40(2):107-12, 1997 Apr. Abstract
The physical effects of negative air ions on humans were determined in an experimental sauna room equipped with an ionizer. Thirteen healthy persons took a wet sauna bath (dry bulb temperature 42 degrees C, relative humidity 100%, 10 min exposure) with or without negative air ions. The subjects were not told when they were being exposed to negative air ions. There were no differences in the moods of these persons or changes in their blood pressures between the two saunas. The surface temperatures of the foreheads, hands, and legs in the sauna with negative ions were significantly higher than those in the sauna without ions. The pulse rates and sweat produced in the sauna with ions were significantly higher than those in the sauna without ions. The results suggest that negative ions may amplify the effects on humans of the sauna.
Terman M. Terman JS.
Department of Psychiatry, Columbia University, New York, NY, USA. Title
Treatment of seasonal affective disorder with a high-output negative ionizer.
Journal of Alternative & Complementary Medicine. 1(1):87-92, 1995 Jan. Abstract
This study was designed to evaluate the antidepressant effect of negative ions in the ambient air as a
potential treatment modality for seasonal affective disorder. Twenty-five subjects with winter depression underwent a double-blind controlled trial of negative ions at two exposure densities, 1 x 10(4) ions/cm3 or 2.7 x 10(6) ions/cm3, using an electronic negative ion generator with wire corona emitters. Home treatments were taken in the early morning for 30 min over 20 days, followed by withdrawals. The severity of depressive symptoms (prominently including the reverse neurovegetative symptoms of hypersomnia, hyperphagia, and fatigability) decreased selectively for the group receiving high-density treatment. Standard depression rating scale assessments were corroborated by clinical impressions. When a remission criterion of 50% or greater reduction in symptom frequency/severity was used, 58% of subjects responded to high-density treatment while 15% responded to low-density treatment (chi 2 = 5.00, df = 1, p = 0.025). There were no side effects attributable to the treatment, and all subjects who responded showed subsequent relapse during withdrawal. Treatment with a high-density negative ionizer appears to act as a specific antidepressant for patients with seasonal affective disorder. The method may be useful as an alternative or supplement to light therapy and medications.
Daniell W. Camp J. Horstman S.
Department of Environmental Health, University of Washington, Seattle 98195. Title
Trial of a negative ion generator device in remediating problems related to indoor air quality. Source
Journal of Occupational Medicine. 33(6):681-7, 1991 Jun. Abstract
It has been suggested that supplementation of indoor air with negative ions can improve air quality. This study examined the effects of a "negative ion-generator" device on air contaminants and symptom reporting in two office buildings. Separate sets of functional and nonfunctional negative ion generators were monitored using a double blind, crossover design involving two 5-week exposure periods. There were no detectable direct or residual effects of negative ion generator use on air ion levels, airborn particulates, carbon dioxide levels, or symptom reporting. Symptom reporting declined at both sites initially and appeared to be consistent with placebo effect. Job dissatisfaction was an apparent contributor to symptom reporting, with a magnitude comparable to presumed effects of air quality. Further testing of such devices is needed before they should be considered for office air quality problems.