Sol-air water treatment [Discussion paper]

The lack of clean water is a significant problem in many developing countries and there is an urgent need for practical, inexpensive, sustainable methods for the production of drinking water, especially on a small scale at the individual and family levels. While the antimicrobial properties of solar radiation have been known for centuries, the recent work of Acra and his colleagues has shown that natural sunlight may be used to decontaminate water in countries with a consistently sunny climate (Acra et al., 1984). However, other studies have provided conflicting data on the effectiveness of solar water disinfection, indicating that additional factors may be involved and limiting the practical application of this technique in the prevention of water-borne disease (e.g. Miller, 1988; MacKenzie et al., 1992). The present study was carried out to evaluate the role of oxygen in solar water disinfection.