Health risks from desalinated seawater used for human consumption: The case of Honaine Plant (Northwest Algeria)

Background: Honaine desalination plant produces 200,000 m3/day of drinking water, and applies a reverse osmosis process with sand/anthracite filters for pre-treatment. Objective: This study aim to explore the quality of treated water (TW) and to address any potential health risks. Methods: Samples of TW were collected daily, three times during the same period, for one month to investigate the physico-chemical characteristics of desalination. They were analyzed for calcium, magnesium, pH, alkalinity, TDS, free-chlorine, hardness, nitrite and sulfate. Results: After comparing the standards set by WHO and Algeria, the results showed that the TW of Honaine plant had low-mineral content, with a noticeable deficiency of calcium (21.22 ± 0.6 mg L-1) magnesium (1.74 ± 0.26 mg L-1), and sulfate (0.02 ± 0.01 mg L-1). The levels of chlorine (0.53 ± 0.08 mg L-1) and nitrites (0.003 ± 0.00 mgL-1) were lower than what the guidelines prescribe. The alkalinity and hardness of the water categorized it as being moderately hard. As for the taste, the TDS value (289.24 ± 26.86 mgL-1) suggests that the TW is excellent but the presence of chlorine negatively influences its palatability. The values of alkalinity value (63.73 ± 1.05 mgL-1) and pH (8.42 ± 0.021) of TW remain in line with recommendations. The hardness value (60.32 ± 0.73 mgL-1) shows that TW is moderately hard and softer than standards. Conclusion: Our findings showed that desalinated TW reflected significant low-mineral content of many healthy elements.