On Monday we reported that not all of the plastic foam containers we see in the islands is imported — some of it is made locally. But most of the foam food containers you buy in a store aren’t from local manufacturers.

The plastic foam supply chain starts a world away.

Foam is made from the byproducts of refining oil.

Take a plastic foam cup, for example, says Michael Hicks, director of the Center for Business and Economic Research at Ball State University in Indiana. “It’s almost certain that the cup you’re holding has oil from overseas,” he said.

Petroleum makes its way from oil-producing countries such as Nigeria and Saudi Arabia to companies in states such as Texas and Pennsylvania.

That’s where John Thayer, a business manager at NOVA Chemicals, comes in. His company turns petroleum byproducts into what’s called polystyrene resin. Think of the resin like tiny plastic granules – they look like salt or sugar, he says. Foam manufacturers mold these granules into plates, cups, to-go boxes, home insulation and a host of other products.

The American Chemistry Council — which represents chemical manufacturers – estimates that the United States produces about 850,000 tons of polystyrene each year.

“This includes (polystyrene) foam building insulation, foodservice, protective packaging and other applications,” Chemistry Council spokeswoman Allyson Wilson wrote in an email to Civil Beat.

When it comes to foam food containers in the U.S., Thayer says, multinational companies like Dart and Pactiv dominate. Dart is known for its foam cups, and Pactiv is responsible for Hefty-brand foam food containers.

Hawaii’s foam food containers probably come from California, says Mark Spencer, business manager for sustainability at Pactiv. That’s because finished plastic foam products are mostly made of air – so they take up a lot more space than the resin does, Spencer says. He says it’s cheaper to ship the resin as close to Hawaii as possible before molding it into containers and insulation.

Just how much foam do we import?

It’s hard to say. Major Hawaii restaurant suppliers either didn’t return phone calls or said they didn’t have answers.

Costco wouldn’t tell us how many foam food containers it sells in Hawaii — the chain says that’s proprietary information.

But you might be able to get an idea from a study the City and County of Honolulu commissioned. The study estimates that about 7,000 tons of polystyrene made its way to Oahu landfills and the H-Power waste-to-energy incinerator in 2006.

The study doesn’t say whether that polystyrene is mostly food containers.

Civil Beat will continue to explore Hawaii’s use of plastic foam, the consequences and benefits in our ongoing series “Friend or Foam.”

Read our related stories about plastic foam in Hawaii:

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