80% of Hong Kong residents flush their toilets with seawater

Chemical & Engineering News - In Hong Kong, about 80% of residents flush their toilets with seawater, thanks to a separate water distribution system set up in the 1950s. The approach conserves the city’s scarce freshwater resources, and has also been adopted by smaller communities like the Marshall Islands. As coastal populations and water demand rise, this idea may become more attractive elsewhere, though some researchers have worried about the release of potentially toxic by-products to coastal areas from treating seawater with chlorination. To the contrary, a new study suggests that the practice not only helps conserve freshwater but also may protect wildlife in marine ecosystems