When will Dunkin' Donuts scrap its Styrofoam cups?

Six years ago, Dunkin' Donuts declared replacing its Styrofoam cups its top sustainability priority. 

Fast forward to 2016, and the majority of Dunkin' Donuts restaurants still serve their coffee in cups made of polystyrene. The company is "not prepared to transition fully out of foam at this time," Christine Riley Miller, Dunkin' Brands' senior director of corporate social responsibility, told Business Insider this week. 

What happened since the report in 2010 that described its use of foam cups as "the most prominent sustainability issue we must deal with"? The report two years later that said the company hoped to find a more sustainable replacement for its cups within two to three years. An increasing number of fast food chains have, in the meantime, begun to adopt more environmentally friendly practices. But Dunkin' Donuts has not.

In recent years, as awareness of the importance of sustainability grows, a number of municipalities across the country have banned polystyrene foam because of its negative impact on the environment: Its production creates large amounts of greenhouse gas, and its non-recyclable nature means it is the main pollutant of oceans and other water sources, the primary source of urban litter, and can cause wild animals to choke and starve. 

In places where foam is banned, Dunkin' Donuts has introduced cups made of a more recyclable plastic known as polypropylene. 

The company has described polypropylene as "the best available alternative to foam," currently. But introducing recyclable cups in all restaurants would come with a number of unique challenges.

For one, Ms. Miller says, the recyclable cups are more expensive to manufacture than the current foam cups. Secondly, many Dunkin' Donuts restaurants are franchises, making it difficult for the company to implement widespread sustainability policies. 

Nevertheless, other chains with a majority franchise restaurants have been able to make the move from Styrofoam cups to paper ones: McDonalds, which aims to have only 10 percent of its restaurants company-owned by 2017, phased out Styrofoam cups and replaced them with paper cups in 2013. 

McDonalds followed Starbucks, one of Dunkin' Donuts's direct competitors, which has used paper cups since the 1980s, as well as smoothie chain Jamba Juice, which announced in 2012 that it would end its use of foam containers and in 2013 introduced a more environmentally friendly cup. 

But paper cups also have their drawbacks compared to foam cups. One study found that only 10 percent of paper food service containers are recycled in major American cities. Furthermore, the cup creates more solid waste. 

"It takes two and a half times as much energy to make a paper cup as it does to make a foam cup," wrote Christopher Bonanos for New York Magazine. "Foam cups are also much lighter than paper cups, reducing the amount of fuel needed to ship them to the store and to cart them away as trash. Foam also produces a lot less manufacturing waste, because there are no paper offcuts to discard." 

One possible solution to the Styrofoam conundrum, suggests chemist Martin B. Hocking in a study for Science, is simply to find better ways to recycle foam. 

"An improved infrastructure," he writes, "is all that is required to make this option a more significant reality and convert this perceived negative aspect of polyfoam use to a positive one."