Clint Swett, Sacramento Bee

A health advocacy group on Monday said that materials used in Apple Inc.'s iPhone were not labeled in accordance with California's anti-toxics law and initiated legal proceedings against the company.

The Oakland-based Center for Environmental Health said the earphone cable that comes with the iPhone contains dibutyl phthalate, a plastic compound that some researchers say causes reproductive damage in women. In 2006 the compound was added to California's Proposition 65 anti-toxic list as a suspected cause of congenital defects.

The group filed a 60-day notice against Apple under terms of Prop. 65, which requires warning labels on such products. It said it would follow with a lawsuit if Apple didn't agree to change the materials in the cable but acknowledged that such a suit might only be able to force a warning label.

Apple officials did not return calls seeking comment.

Caroline Cox, a spokeswoman for the Center for Environmental Health, said she hoped her organization could negotiate an agreement with Apple to modify the cable.

"A company typically would rather reformulate than have a label on its product saying it could cause reproductive harm," she said.

Cox said the center had taken similar actions against makers of jewelry and lunch boxes in recent years and invariably has been able to reach settlements.

Her group chose to focus on the iPhone because it was a high-profile product that would draw attention to use of toxins, she said.

"Because the iPhone is an icon of modern technology, it should be free of toxic chemicals," she said.

On Sunday, Gov. Arnold Schwarzenegger signed a bill banning phthalates in children's products.