Apple Inc.'s eye-catching logo — an apple with a bite taken from it — has come in many colors in the past.

Now the iconic computer company is trying to prove its commitment to the color green.

In recent advertising, the Cupertino, Calif., company presents itself as an environmental leader. Apple's Web site bills its new line of MacBook computers as "the world's greenest family of notebooks."

It now makes iPods and iPhones free of polyvinyl chlorides and brominated flame retardant, and it's in the final stages of making all of its products without bromine and chlorine. Both chemicals have been criticized for creating toxic byproducts.

Competitors and environmentalists, however, say Apple's green efforts have less to do with cleaning up its products and manufacturing and more to do with marketing.

In a recent blog posting, a senior executive at Round Rock, Texas-based Dell Inc. said he was "surprised" by Apple's claims of environmental-friendliness. Environmental groups, like Greenpeace, point to surveys ranking Apple below other computer makers, such as Dell and Hewlett-Packard Co. in green practices.

"Apple is ... guilty of using 'green' as a marketing ploy, rather than making green a core part of their business practices," said Stephen Stokes, vice president of business and climate change at AMR Research Inc.

A recent survey by the Diffusion Group, a Dallas research company that studies the impact of green products on consumer decisions, found consumers view Apple as the world's greenest company.

"Chalk it up to effective marketing," said Michael Greeson, president of the Diffusion Group, of Apple's green reputation.

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