The next time you start your dishwasher, feel good that you may be striking a blow for cleaner local streams and the Chesapeake Bay.
As of July 1, all dishwasher detergent sold in Pennsylvania and 15 other states had to be free of all but a trace of phosphates.
Until now, dishwasher detergents could contain up to 9 percent phosphorus (by weight), about the same found in common houseplant fertilizers.
Phosphorus is a traditional cleaning agent.
The ban in Pennsylvania is the result of legislation authored by state Sen. Michael Brubaker of Lititz and was signed into law by Gov. Ed Rendell in May 2008. The legislation was passed unanimously by the state House and Senate.
Phosphorus, banned in laundry detergents in Pennsylvania since 1989, is a prime pollutant of streams and the Chesapeake Bay.
Though found in nature, too much phosphorus acts like a fertilizer and spurs the growth of algae and aquatic weeds. When they die, their decomposition depletes oxygen needed by fish and aquatic life.
The main source of too much phosphorus flowing into the Chesapeake Bay and local streams is runoff from agriculture and urban and suburban development, but controlling phosphates from sewage plants is one way to reduce levels.
When he introduced legislation to ban phosphates from dishwasher detergent, Brubaker estimated that 7 percent to 12 percent of the phosphorus entering sewage plants came from automatic dishwashing detergents.
With pressure mounting on the state and communities to reduce nutrients flowing into the Chesapeake Bay, Brubaker hopes the ban will ease the burden just a little.
Plus, he said, reducing the flow of phosphorus should save municipal sewage treatment operators money.
"Because we're under new guidelines from the federal Clean Water Act to reduce nitrogen and phosphorus, it makes sense to me to modify and exclude what goes into the plants," Brubaker said Tuesday.
His comments were echoed by Harry Campbell, science advocate for the Pennsylvania office of the Chesapeake Bay Foundation.
"Scientists have found that 9 percent to 34 percent of phosphorus going into sewage plants comes from residential dishwashing detergent. Certainly that's a benefit in terms of helping our wastewater plants in achieving load requirements for the Chesapeake Bay," Campbell said.
Also, he said, in times of dry weather, such as now, some streams receive most of their flow from discharges of wastewater from sewage plants.
Most of those are classified as impaired because of high phosphorus loadings.
Thus, less phosphorus in sewage plant wastewater can boost water quality significantly, he said.
"This will help our local streams out."
In addition, old septic systems in rural areas perform less effectively with phosphorus over time, he said.
The ban does not apply to commercial dishwashing products. Detergents for hand-washing dishes generally contain no phosphorus.
Manufacturers of dishwashing detergents were given two years to come up with alternatives without phosphorus and time to clean out their inventory.
The bans went into effect in all 16 states simultaneously partly to give detergent manufacturers a consistent timeline for compliance and so that consumers wouldn't be running to other states without a phosphate ban to horde detergents.
There have been recent stories about consumers in Pennsylvania traveling to New Jersey to buy detergents.
Brubaker said he has heard the stories. But he said he was assured by manufacturers two years ago that they have replacement cleaning enzymes just as effective at cleaning dishes as phosphorus. Early substitutes were not as effective, he said.
A ban on dishwasher detergents was not made in 1989 because automatic dishwashers were not as prevalent and manufacturers sought time to come up with economical alternatives.
Campbell said that switch has been made.
"It's been an evolution in the marketplace," he said. "We no longer need phosphorus."
The other 15 states instituting the ban are Illinois, Indiana, Maryland, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, Ohio, Oregon, Utah, Vermont, Virginia, Washington and Wisconsin.