联合国：海水淡化厂危害环境

A recent United Nations report has found desalination harmful to the environment. Desalination is the process of removing salt from seawater for use by humans and in agriculture.

Almost 16,000 desalination factories around the world produce huge flows of highly salty waste water and dangerous chemicals, the study said.

The study comes from the Institute for Water, Environment and Health at U.N. University, or UNU. Vladimir Smakhtin is the director of the institute. He said the study was part of research into how best to secure fresh water for a rising population without harming the environment.

Desalination plants release 142 million cubic meters of salty brine every day, 50 percent more brine than formerly estimated. Brine is water containing large amounts of salt and often includes chemicals such as chlorine and copper used in desalination. The salty brine is mostly released into the sea.

Edward Jones is the lead writer of the report. He explains that brine can cut oxygen levels in seawater and cause serious harm to sea animals, including shellfish. This harm leads to observable damage throughout the food chain.

Alex Drak is an engineer at IDE Technologies in Israel, a leading desalination firm. He said brine that is processed correctly dissolves quickly in the sea.

"We see a lot of marine life, different types of fish," near where the brine is released, said Drak, who was not involved in the UNU study.

Desalination is a fast-growing private industry that uses massive amounts of electrical energy. It is also one of the most expensive sources of water. However, many of the world's dry areas depend on it.

A little more than half the brine comes from factories processing seawater in Saudi Arabia, the United Arab Emirates and Qatar, the study reported.

I'm Alice Bryant.

Alister Doyle reported this story for Reuters news agency. Alice Bryant adapted it for Learning English. Kelly Jean Kelly was the editor.