Your Laundry Detergent Probably Contains This Dirty Ingredient

Corn-based ethanol can be dirtier than you think. Now Tide is dropping it in favor of a more environmentally friendly option.

(Photo: Joe Raedle/Getty Images)

Oct 7, 2014· 1 MIN READ
Katharine Gammon has written for Nature, Wired, Discover, and Popular Science. A new mom, she lives in Santa Monica.

Oil from corn doesn’t immediately come to mind as a key ingredient in laundry detergent, but it is one.

On Tuesday, Procter & Gamble, which makes Tide, announced it would start making its Tide Coldwater Clean detergent using ethanol derived from corn stalks, leaves, and cobs, rather than from corn. That’s a win for the environment, because the new process removes 7,000 tons of agricultural waste a year and uses it to make the new oil— producing zero net carbon emissions.

"The conversation around cellulosic ethanol has long focused on its use as a transportation fuel, but this technology has the potential to be used in a variety of industrial applications,” said James Collins, senior vice president at DuPont, which has partnered with Proctor & Gamble on the product's creation. “With this collaboration, DuPont is taking the first step to diversify its markets for cellulosic ethanol beyond fuels. Looking ahead, we will continue to seek out new opportunities and new collaborations to transform value chains with more sustainable solutions.”

Corn-based ethanol has long been an ingredient in Tide; it was originally added to stabilize the detergent formula and improve washing performance. But the switch to cellulosic ethanol negates emissions from more traditional ethanol production methods by reducing agricultural waste—but not at the expense of the detergent's ability to fight tough stains.

Right now, the company plans to use the new ethanol in its Tide Coldwater Clean detergent, a product released in February that allows users to wash clothes in water at around 60 degrees Fahrenheit instead of 90, removing the need to use energy to warm up water. Roughly 45 billion laundry loads are cleaned in homes in the United States each year, and that creates 40 million metric tons of carbon dioxide emissions. If people start washing loads in cold water, the energy savings could reduce those emissions by 32.3 metric tons—the equivalent of the electricity use of 3.7 million U.S. homes, according to DuPont.

But making all that ethanol will require a new factory, and for that, Tide looks to DuPont, which plans to produce the cellulosic ethanol at its biorefinery in Iowa. When it opens later this year, it will be the largest cellulosic ethanol plant in the world, producing 30 million gallons of the stuff annually.

The material for the ethanol will be sourced from local farmers, the companies say, and they’ll be adding jobs to the region. To supply the corn leaves, stalks, and cobs for its plant, DuPont will contract with more than 500 farmers to gather, store, and deliver more than 375,000 dry tons of material.

Procter and Gamble has been working to make its factories more sustainable overall; 25 percent of its facilities now produce zero waste. The company also announced earlier this year that it will drop phosphates from its detergents by 2016.