Purified wastewater vs conventional drinking water

While purifying municipal wastewater as a potable water supply is considered a sustainable alternative to expand water supplies in drought-prone regions, lingering concerns about health risks have hindered implementation. Now a new Stanford University study, published in Nature Sustainability, indicates that the toxicity of potable reuse waters is equal or lower than conventional drinking waters.

The research team, led by Professor William Mitch, directly compared potable reuse waters and conventional drinking waters serving the same areas using mammalian cell cytotoxicity assays. The cytotoxicity of potable reuse waters treated using reverse osmosis membranes was much lower than that of conventional drinking waters.

The research found that despite its sewage origin, the extensive treatment applied to purify potable reuse waters can produce a safe, energy-efficient and cost-effective alternative water supply.

The findings indicate that a new regulatory approach may be needed to better protect public health.

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