The desirable range of pH for drinking water is

The desirable pH range for drinking water is 6.5 to 8.5. This standard is globally recognized by major health and regulatory bodies. According to the World Health Organization (WHO), the pH of most drinking water lies within the range of 6.5–8.5 [2]. In India, the Bureau of Indian Standards (BIS) specifies in IS 10500:2012 that the acceptable limit for pH in drinking water is 6.5 to 8.5 [1]. Maintaining this range is crucial because water with a pH below 6.5 can be corrosive to plumbing and may leach toxic metals like cadmium or lead into the supply [2]. Conversely, water with a pH above 8.5 may have a slippery feel or a soda-like taste. While the human body typically functions within a narrow internal pH range of 7.0 to 7.8, the external intake of water within the 6.5 to 8.5 range is considered safe and non-detrimental to health [1].

Sources

1. [2] https://cdn.who.int/media/docs/default-source/wash-documents/wash-chemicals/ph.pdf
2. [1] https://cpcb.nic.in/wqm/BIS_Drinking_Water_Specification.pdf