Dunkin' Donuts, under pressure from an activist group, has agreed to phase out a controversial whitening agent used in the powered sugar atop some of its doughnuts.

The move wasn't announced by the doughnut kingpin, but by the advocacy group As You Sow. The group had submitted a shareholder request asking Dunkin' Brands to reduce the use of titanium dioxide in its powdered sugar. As You Sow officials claim that titanium dioxide is a "nanomaterial" — a substance engineered to have extremely small dimensions, which the advocacy group claims can be toxic to humans.

In a statement e-mailed to USA TODAY, Dunkin' Brands chief communications officer Karen Raskopf said that the titanium dioxide is not a "nanoparticle" under the Food and Drug Adminstration's definition, but that Dunkin' had still agreed to stop using it.

"The ingredient used in our powdered doughnuts does not meet the definition of 'nanoparticle' as outlined under FDA guidance," Raskopf said. "Nevertheless, we began testing alternative formulations for this product in 2014, and we are in the process of rolling out a solution to the system that does not contain titanium dioxide."

In a second statement e-mailed to USA TODAY, Raskopf said the move was relevant to investors. "Dunkin' Brands understands that investors are increasingly interested in the sustainability of the companies in which they invest. As part of our ongoing stakeholder engagement process, we recognize the importance of engaging in productive, ongoing dialogues with our investors to understand and address their concerns, as appropriate."

The move comes at a time when consumers and activist groups are paying closer attention to the ingredients big foodmakers and sellers from McDonald's to Subway put in their foods. Earlier this week, McDonald's revealed plans to phase out antibiotic use in its chicken supply. Last year, Subway agreed to remove a controversial chemical called azodicarbonamide from its bread shortly after one nutritional activist noted the same chemical is used in yoga mats.

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http://www.usatoday.com/story/money/2015/03/06/dunkin-donuts-fast-food-restaurant-food-safety/24524875/