Original sentence: Centers for Disease Control and Prevention listed water fluoridation as one of the ten great public health achievements of the 20th century; in contrast, the European Union, Directorate-General for Health and Consumers regards water fluoridation, controversial as a public health measure.Most European countries have experienced substantial declines in tooth decay without its use, primarily due to the introduction of fluoride toothpaste in the 1970s.Public water fluoridation was first practiced in the USA, and has been introduced to many other countries to varying degrees with many countries having water that is naturally fluoridated to recommended levels and others, such as in Europe, where some countries fluoride is added to table salt, an alternative source of fluoride..
Edited sentence: Centers for Disease Control and Prevention listed water fluoridation as one of the ten great public health achievements of the 20th century; in contrast, most European countries have experienced substantial declines in tooth decay without its use, primarily due to the introduction of fluoride toothpaste in the 1970s.Public water fluoridation was first practiced in the USA, and has been introduced to many other countries to varying degrees with many countries having water that is naturally fluoridated to recommended levels and others, such as in Europe, using fluoridated salts as an alternative source of fluoride