PARTITIONING OF ORGANIC-CHEMICALS AT THE AIR-WATER-INTERFACE IN ENVIRONMENTAL SYSTEMS

It is suggested that partitioning of organic chemicals to the air-water interface can be significant and must be quantified in several situations of environmental interest including partitioning of chemicals into small air bubbles in water into small water drops in air (for example, fogs), and between the phases present in relatively dry soils. Experimental data are reported for interface-air partitioning of a variety of chemicals and are consolidated with previous data to show that interfacial partitioning is primarily controlled by the chemical's hydrophobicity. Correlations are derived for interface-air and interface-water coefficients from data for 44 polar and nonpolar chemicals. The environmental implications of interfacial partitioning are discussed, and methods are suggested for including the interface as a compartment in mass balance calculations involving air bubbles, water drops, and soils.