The Spokane river had a soap-scum problem. Runoff from the region's dishwashers was loaded with phosphorus, which helped get glasses and plates sparkling clean but was also fueling the growth of algae, which, in turn, were making Washington State's waterways an icky green. Besides repelling swimmers, the algae were sucking up so much oxygen they were suffocating other aquatic life. Experts estimated that as much as a third of the phosphorus at wastewater-treatment facilities was from dishwasher detergent. The other main phosphorus sources are fertilizer and sewage, and since farmers need fertilizer to grow crops--and since there's no easy way to get people to poop less--a group of environmentalists decided to focus on detergents.
In 2006 the activists managed to push through the first statewide ban on phosphates in household automatic-dishwasher detergents, though it didn't take effect until this year because of an industry compromise. Since then, 15 other states have followed suit. "There was a really broad constituency for the idea of getting these chemicals out of the [wastewater] system," says Rachael Osborn, a public-interest lawyer who worked on the Washington campaign, which has significantly reduced the amount of phosphorus reaching Spokane water-treatment plants.
The slew of state regulations helped lead the American Cleaning Institute (ACI), the trade group that represents most detergent manufacturers, to adopt a voluntary ban this past summer. This means it won't be long before phosphate-laden detergents essentially disappear from U.S. store shelves--a major victory for clean-water advocates. Another positive development for the antiphosphate crowd: on Nov. 4 the European Commission proposed a ban on phosphates in laundry detergent sold in the E.U., something the U.S. put into effect nearly two decades ago.
But if you're thinking of breaking out the champagne flutes, don't be surprised to see some spots on them. One reason detergent makers have been using large amounts of phosphorus is that it binds with dirt and keeps it suspended in water, allowing the other cleaning agents to do their best work. Phosphorus is especially important in regions with hard water because the presence of lots of minerals can interfere with cleaning agents. "Phosphorus is just amazing in grabbing onto stuff," says Dennis Griesing, ACI's vice president of government affairs. "It's a very sociable element."
Although Consumer Reports recently tested 24 top phosphate-free detergents and rated several as very good, none of them cleaned as well as the top-rated phosphate products. Greener detergents often cost more too. This helps explain why some Washington residents have reportedly driven to Idaho to smuggle in phosphate-intensive detergents.
The E.U.'s proposed antiphosphate regulations don't include dishwasher detergents, declaring that "more research and innovation is still needed to develop adequate alternatives." That's a mistake, greens say. "Phosphorus is a known pollutant," says Jonathan Scott, spokesman for D.C.-based Clean Water Action. "If we remove it upstream [from detergents], we won't have to spend to remove it downstream." And less-than-sparkling dishes seems a small price to pay for a cleaner planet.
This article originally appeared in the November 22, 2010 issue of TIME.