State ban on phosphorus in dishwasher detergents will help protect lakes
Thirty-five years ago, Indiana became the first state in the nation to protect its lakes and waterways by prohibiting the use of laundry detergents containing phosphorus.
Bill Jones
Now the state has taken another step to protect surface waters from nutrient pollution. Thanks to the efforts of an Indiana University Bloomington professor, the legislature extended the phosphorus ban to detergents used in residential automatic dishwashers.
"It's a step in the right direction," said Bill Jones, a faculty member in the School of Public and Environmental Affairs, who proposed the legislation as a member of the Indiana Lakes Management Work Group. "There are alternatives (to using phosphorus in detergent). And this will help the environment."
Phosphorus, along with nitrogen, is a nutrient that, when added to lakes, stimulates excessive growth of algae and vegetation -- a process, called eutrophication, that can severely damage water quality and ruin aquatic ecosystems. In most freshwater lakes, phosphorus is the "limiting nutrient:" More phosphorus means more algae growth.
Jones, who teaches a SPEA course each spring in lake and watershed management, knew that some types of automatic dishwasher detergent are high in phosphorus. And he decided last fall that the time was right to try to do something about it.
Indiana was the first state in the nation to protect its lakes and waterways by prohibiting the use of laundry detergents containing phosphorus. Now the state is looking to protect water from nutrient pollution.
He worked with state Rep. Nancy Demboski of Knox, Ind., and the Legislative Services Agency to draft House Bill 1120, which prohibits the use of dishwasher detergents with phosphorus. In a "short session" of the legislature, focused chiefly on property tax relief, the phosphorus bill passed by margins of 85-7 in the House and 46-0 in the Senate. Gov. Mitch Daniels signed it into law on March 3.
"Eliminating phosphorous in dishwasher detergents is one more step we need to take to preserve the natural ecosystems of Indiana's lakes and rivers," Dembowski said upon approval of the legislation.
Indiana is one of about a half-dozen states to enact bans on phosphorus in dishwasher detergents, Jones said. Commercial automatic dishwashers were exempted after industry officials argued that enzyme-based alternatives to phosphorus detergents may not be effective in the extremely high temperatures reached in commercial machines. The ban doesn't take effect until July 2010, giving the industry time to adjust.
How much of an impact will a ban have? According to the Minnesota Pollution Control Agency, residential and commercial dishwashers contribute 3 percent of the phosphorus going into surface waters in that state. It's likely that the situation in Indiana is similar. So eliminating phosphorus from all dishwasher detergents could reduce nutrient loads in lakes by about 3 percent, resulting in less algae and plant growth.
Jones said excessive use of phosphorus as a fertilizer for suburban lawns is a bigger factor in damaging Indiana lakes. But getting the phosphorus out of automatic dishwasher detergents is something the state can do now to protect its surface waters.
"The lakes may not turn crystal clear -- of course they won't," Jones said. "But it will reduce the biomass of algae. It's one piece of a very big puzzle."
