April 29, 2008 - Supermarket chain Tesco today began testing carbon labels on 20 store items from potato chips to lightbulbs in a bid to educate consumers on products' climate impact from "seed to store," Reuters reports.

Tesco CEO Sir Terry Leahy has pledged to roll out carbon labels for each of the 70,000 products the company carries, although no timetable to expand the program has been set.

"Let's see what the response to this is and in the meantime we'll measure the emissions of more products," says David North, Tesco's community and government director. "This is a pilot, it has to be a pilot because we have to be sure it works. There isn't consensus about every piece of data and you wouldn't expect there to be."

Tesco's carbon-labeling initiative is backed by the U.K. Environment Ministry and the Carbon Trust, a government-funded program to develop commercial low-carbon technologies.

For more on the pluses - and pitfalls - of carbon labeling, click here.