Today, New Hampshire adds automatic-dishwater detergent to the list of cleansing products that cannot contain high levels of phosphate, the latest step in the long fight to reduce a substance that causes algae blooms and other problems in state waterways.

“It’s a giant step forward. Anything that any of us can do to remove phosphorus from lakes and rivers is good,” said Jody Connor, director of the Limnology Center for the state Department of Environmental Services.

The ban on high-phosphate dishwater detergent goes into effect today in 16 states, including Massachusetts and Vermont as well as New Hampshire. For practical purposes it is a nationwide ban, since the industry agreed several years ago to remove the compound in return for uniform regulations and being given more time to formulate products. It also applies in Canada.

“Having the same regulation at the same time, that’s what was critical for us,” said Dennis Greising, vice president of government affairs at the American Cleaning Institute, an industry group.