Chemical and microbial quality of bottled drinking water in Gonabad city, Iran: Effect of time and storage conditions on microbial quality of bottled waters

Reports from bottled water (BW) industries show a rapidly increasing rate of global bottled water consumption. The present paper contains data on chemical and microbial quality of bottled waters marketed in Gonabad city, Iran. The data on the effect of time and storing conditions on microbial quality of bottled water also is reported. The physical and chemical parameters of all 9 studied BW brands meet well with those mentioned on the labels. All BW sampled also were free of pathogenic indicators (total coliforms, fecal coliforms, fecal streptococci and clostridium perfringens). BWs kept in refrigerator have minimal heterotrophic and pathogenic bacterial count. The highest bacterial count was observed when BWs were exposed to indirect sunlight at room temperature. Presence of heterotrophic and especially pathogenic bacteria reduced significantly when the samples were placed to direct sunlight. In all samples, apart from where they were kept, the heterotrophic and pathogenic bacterial counts showed an increasing trend after bottling.