Some observations on the physiological effects of gaseous ions

This paper reviews some of the evidence pertaining to the biological effects of gaseous ions. It appears to us that experimental data now available warrant the conclusion that reproducible biological effects occur in a variety of living forms including microorganisms, higher plants, insects, animals and man. The responses generally are limited in extent and to indict air ions as their sole cause requires great care in defining the experimental conditions. Some progress has been made in detecting the fundamental biochemical reactions associated with ion-induced physiological changes. The ready availability of excellent apparatus for generation and measurement of air-ions, coupled with present-day knowledge about their properties, makes critical experimentation possible.