Microbiological beach sand quality in Gaza Strip in comparison to seawater quality

Gaza beach is the only recreational area available for the local inhabitants. It is heavily polluted with treated, partially treated, and untreated sewage from point and nonpoint sources. The majority of the population is below the age of 15 years. This age group is vulnerable to gastrointestinal diseases and usually restricts their activities to beach sand at the swash zone. Five sampling points along the Gaza beach were selected and monitored for 1 year (fortnightly). Microbial sand content was evaluated for fecal coliforms (FC), fecal streptococci (FS), Salmonella, Shigella, and Vibrio. Seawater samples were subjected to similar evaluation. Pseudomonas, yeast, and mold counts were performed for all sand samples as possible sand pollution indicators. Higher fecal indicators (both FC and FS) were obtained in sand than in water in most locations. The frequency of Salmonella and Vibrio isolation was also higher in sand than in water despite the fact that only 10 g of sand were used while 1L of seawater was collected. Statistically significant correlations between FC and streptococci and between Salmonella and Vibrio were found. Similar correlation was also detected between Pseudomonas and Salmonella in sand samples.