Physical and Chemical Components of Cuba’s Rain: Effects on Air Quality

The objective of this study was to analyze the influence of the physical and chemical components of rain affecting air quality in Cuba. Samples were obtained from pollution monitoring stations throughout Cuba. Different chemical analyses including elements and ions were conducted. Meteorological data was also included for the analysis. Results show that the pH was slightly basic for most stations, except those of the eastern region which exhibit pH values below 5.6. The major anthropogenic sources of ions are the burning of fossil fuel by power plants, cement factories, and nickel-processing industries and the burning of biomass through poor agricultural practices. The western region exhibited increased concentrations of and during the dry season, most likely due to the long-range transport of pollutants from the northeastern United States as well as local pollutants. Marine aerosols clearly influence Cuba’s rain. Only a small fraction of the potentially acidic ions contributes to the free acidity of Cuba’s rainwater, mainly due to the neutralizing capacity of some ions such as Cl-, Na+, Ca+2, and . The implementation of abatement techniques for SO2 and NOX and some elements emissions from major stationary sources will be an effective measure to improve air quality in Cuba. 1. Introduction The fall of rain, snow, fog, and dew is the mechanism that permanently removes gases and particles from the atmosphere [1], an important role, especially in countries with a humid climate. The acidity and the concentration of ions in rainwater depend on the type and magnitude of its sources, its physical incorporation into the water system, and the chemical transformation during the formation of clouds and drag below them [2]. Acid rain is any form of wet precipitation of pH < 5.6 [2]. Acid rain is a major environmental problem, especially across national boundaries in the Northern Hemisphere due to the movement of air masses over long distances [2]. In recent years such movement has spread to other parts of the world, especially Asia and tropical countries, becoming a problem for the tropics due to its abundant precipitation [3]. Acid rain reduces growth in trees and increases their vulnerability to pathogens and pests and causes leaching of nutrients, acidification of soils, and modification to the ecology of lakes. Acid rain also causes the dissolution of CaCO3 in the monuments and buildings of limestone or marble [4]. Rainwater contains elements in the range of μg/L, some of which dissolve at acid pH, affecting human health and the ecosystem. The presence of those