Men and women of different ages were submitted to the activity of negative or positive air-ions several hours a day for from several to more than a dozen days. Shifts in their systolic/diastolic pressures and pulse were determined in the course of these experiments.
The tests have shown a statistically significant influence of the ionized particles, above all on blood pressure. Exposing humans with proper circulatory indicators six hours a day for more than a dozen days to negative air-ions in concentrations of 10,000 ions/cm³ results in a 5% drop in systolic pressure and around 2% drop in diastolic pressure, but has no influence on the pulse. This effect works until both pressures reach a stable level, which probably can be considered optimal for a given person. However, exposing people to positive air-ions in concentrations of 25,000 ions/cm³ results in destabilization of the circulatory indicators.