IONS CREATED BY WINDS MAY PROMPT CHANGES IN EMOTIONAL STATES
By WALTER SULLIVAN
Published: October 6, 1981
FOR many years it has been suspected that certain weather conditions, notably such hot, dry winds as the foehn in Europe, the sharav in Israel and the Santa Ana in southern California, affect people's mood and health, even precipitating suicides, crimes and accidents.
One controversial explanation -electrification of the atmosphere by positive ions - has now acquired greater plausibility through a series of experiments on volunteers at New York University.
The findings, the researchers said, ''are potentially quite important, as atmospheric charge is a fundamental part of the air we breathe.''
''Since altered ion concentrations can result not only from changes in weather conditions but also from the presence of pollutants, highvoltage lines, and radioactivity,'' they said, ''the possibility of far-reaching implications emerges.''
Normally molecules of oxygen, nitrogen and other elements in the air carry their full complement of electrons and are therefore electrically neutral. In various ways, however, an electron may be knocked off such a molecule, leaving it with a positive charge. It is then a ''positive ion.''
The liberated electron may attach itself to a molecule that already has a full complement of electrons, whereupon the molecule becomes a ''negative ion.''
Positive ions may be generated by hot winds, radio and television transmitters, ventilators or direct current power lines. For a number of years some people, to neutralize the allegedly deleterious effects of such ions, have installed negative ion generators in their homes or offices.
When, in the 1950's, ion generators were intensively marketed as effective against a variety of diseases, the Food and Drug Administration forced the salesmen to claim only that the generators help clean the air.
Ever since then the scientific community, with some exceptions, has looked down its nose at suggestions that ions affect human health and behavior. Now, however, researchers believe they have documented some psychological effects of positive ions.
The experiments are described by Dr. Jonathan M. Charry of Rockefeller University and Dr. Frank B.W. Hawkinshire 5th of N.Y.U. in a recent issue of the Journal of Personality and Social Psychology.
The apparent effects of positive ions included increased tension and irritability as well as a slowing of reaction times. The reaction times were measured in terms of the lag between appearance of a red light and the pressing of a button by the subject.
These effects, however, were not obvious when findings from all 85 subjects were lumped together. They were evident chiefly when results from the 34 subjects with a less resilient autonomic nervous system were separately examined. The autonomic system controls reflexes, heart performance and the other involuntary functions. Its resilience can be seen, for example, in the return of heart rate to normal after a fright.
In an interview last week Dr. Charry pointed out that the study was the first conducted in this manner and its findings must be considered tentative until replicated elsewhere.
Much of the early research on this subject was conducted in Israel, where the sharav has a marked effect. It has been reported that 30 percent of the population becomes ill with migraine, nausea, vomiting, irritability, dimness of vision, respiratory symptoms and other effects.
The symptoms are said to appear a day or two before heat and dryness become severe, but when air blowing in from the desert is already laden with positive ions. Such winds in other parts of the world have also been associated with increased crime, suicide and accidents. These winds, in addition to the foehn, sharav, and Santa Ana, include the chinook of the Pacific Northwest, the sirroco of Italy, the ghibli of Libya and the zonda of the Argentine Andes.
The results of the current research derive some support from mouse experiments conducted for over two decades by Dr. Albert Paul Krueger and his colleagues at the University of Californ ia in Berkeley.
They have reported that exposure to high levels of positive ions raises blood levels of the hormone serotonin, a substance that has generated much recent research in a number of fields as scientists increasingly appreciate the hormone's importance in behavior. Negative ions have the opposite effect on serotonin in the blood. Both types of ion, however, depleted brain levels of the hormone. As noted by Dr. Charry, analysis of brain t issue of suicides has shown reduced levels of the hormone, as has c erebrospinal fluid from depressed people. In Israel, during a sharav, excess amounts of serotonin have been found in the urine of tho se classed ''weathersensitive.''
The discovery in mice that negative, as well as positive, ions depress brain levels of the hormone, Dr. Charry said, suggests that long exposure to artificially produced ions might be harmful. He and his colleagues are now conducting tests with rats to determine the effects on brain and behavior of various ion doses and lengths of exposure. Later they hope to continue the human tests.
The new results, according to Dr. Charry, suggest that much more needs to be known of ion effects on the body before the usefulness of devices generating negative ions can be assessed.
In the N.Y.U. experiments the volunteers were told that, while details regarding the purpose of the tests would be withheld until afterwards, lest they bias the results, the goal concerned factors that lead pilots and drivers to commit fatal errors. Each person was tested twice in the experimental chamber: once with the ion generators on and once with them off. The volunteers were unaware of the generators' role.
Whether each person was first tested with the generators on or off was randomly determined. The two sessions were spaced three days apart. The test for resilience of the autonomic nervous system was one widely used by heart specialists since that system controls heart performance and blood pressure.
It involves plunging one hand into cold water while electrodes attached to the palm of the other hand record changes in its electrical conductivity. The response was interpreted to identify those whose autonomic nervous system is less resilient.
It was those who proved most ion-sensitive. For members of this category the lag between display of a red light and the buttonpushing response increased after ion exposure.
Also used was a standard psychological test, known as the Nowlis Mood Adjective Checklist. Each subject was given an alphabetized list of 100 adjectives and asked to indicate those nearest his or her state of mind - from adaptable, adventurous, aggressive and so on to worried.
Scoring depended on the clustering of responses in various categories. The subjects were also rated on such subjective symptoms as headache, dizziness, blurred vision and drowsiness. The results, after ion exposure, showed reduced scores in the categories labeled sociability, surgency (elation) and task involvement.
Scores showed an increase in tension, inattention and fatigue. Males appeared more susceptible than females, but it was suggested that the women might be vulnerable to long-term exposure. The tests lasted only 90 minutes.
Those whose autonomic nervous systems appeared highly resilient - two-thirds of the total - showed no ion effects. ''It appears that consideration of individual differences in ion sensitivity,'' wrote the researchers, ''is essential for assessing performance effects of ions.''