The influences of air pollution (due to smoke and sulfur dioxide) and wind speed on large-ion concentration (LIC) for the period from 1969 to 1980 are examined. In addition, the variations of LIC during sea breeze and etesians days for the same time period are presented. It was shown that wind speed and LIC are anticorrelated, while LIC is significantly lower during Etesian winds in comparison with that during sea breeze. The effects of ozone and nitrogen dioxide on LIC for the period 1982--1984 are also examined. It was shown that increase of smoke and/or sulfur dioxide leads to increase of LIC, while LIC and ozone, nitrogen dioxide are anticorrelated. ¿ 1998 American Geophysical Union