Congressional office in Washington, the capital of America has recently undergone an incident of lead in drinking water exceeded; on July 5th, Capitol Building Department announced that they will arrange blood lead levels detecting for the congressional members and staff for free. A week ago, congressional office has detected the excessive of the lead level of the drinking water, then the drinking water pool was suspended; It is reported that, at least a pregnant woman of the employee of Congress has drunk the “lead water", we knew that the lead is particularly harmful for the unborn fetus; previously, Flint, Michigan City was exposed the water pollution crisis, and dozens of children were detected lead levels excessive. June of this year, source has reported that the problem of lead contamination of drinking water of United States is very common, cheating has been taken to conceal the problem of excessive amount of lead in water in many places.

 

Lead, a toxic heavy metal, is the known toxic substances which recorded most in the book, some ancient books has recorded that the use of lead pipes conveying water is dangerous. However, there are still a lot of water pipes of some parts in homes and buildings are made of lead. These lead making water pipes are the main supply pipe or part of the pipeline which is connected to the residents of the home, thus part of lead will dissolve in the water to cause lead pollution.

 

In recent years, tungsten trioxide (WO₃) as a photocatalyst material has caused great concern; WO₃ with semiconductor property, its photocatalytic reduction effect is shown to effectively solve the pollution problems of chromium, mercury, lead and other heavy metal ions. Especially, the WO₃ with nano particle, due to its large specific surface area, it can fully enhance the efficiency of the reaction. However, the pure tungsten trioxide is easy to occur the light corrosion, and with the low utilization of visible defects and difficult to obtain a stable light catalytic properties, therefore, the modification technologies of metal ion doping, such as yttrium (Y), praseodymium (Pr) and so on; non-metal-doped miscellaneous, such as C; semiconductor composite, WO₃/ZnO, WO₃-TiO₂ ect.; polyhydric doping are used to enhance its property. With the continuous researching on photocatalyst, tungsten trioxide photocatalyst will play a huge role in the lead pollution and other water contamination.