Sept. 17, 2007 Global brands PepsiCo and Wal-Mart are considering following in the, ahem, footsteps of footwear pioneer Timberland, which began including a "carbon nutritional label" on its product packaging in 2006.

Australia's The Age notes that potato chip maker (and Pepsi subsidiary) Walkers earlier this year began placing carbon labels on its products thanks to a pilot project supported by the British government.

The difficulty in accurately calculating the emissions from a product's manufacture continues to challenge companies considering a move to carbon labeling. Wal-Mart has begun by hiring consultants to calculate the carbon emissions created by several of the products, according to the article. Other companies, including computermaker Dell, are beginning to collect emissions data from suppliers in an effort to gather information that might someday make its way onto product labels, the article suggests.