The vote came just one day after research with Bay Area ties found that heavy mobile usage is much higher than previously thought.
With ten "yes "votes, San Francisco once again made history, becoming the first city in the nation to require that customers know the radiation levels of each and every cell phone sold by retailers.
It was what supporters of the measure were waiting for. Ginger Farver of Colorado lost her son to a brain tumor she says was caused by his cell phone use.
"His neurosurgeon told us that he believed it was his cell phone usage," she told ABC7.
Stores will have to post the radiation levels of every make and model of cell phone. But, just last month, a major study called the "Interphone Cell-Phone Safety Study" found that to date, no adverse health effects have been established for cell phone use. That research prompted the cell phone industry to note the many studies already done.
In a recent statement, the Wireless Association said, "Interphone's conclusion of no overall increased risk of brain cancer is consistent with conclusions reached in an already large body of scientific research on this subject."
However, on Monday, Bay Area researcher Lloyd Morgan disputed the findings of the Interphone study at a conference in South Korea. Like Morgan, Ellie Marks is a member of the America's Environmental Health Trust lobby group.
"The Interphone study greatly underestimated the risk of brain tumors from cell phones to the point of at least 25 percent," she said. "There were 25 percent more brain tumors than what they reported."
Supervisor Sean Elsbernd voted against the measure. He thinks any standards should be set by the Federal Communications Commission (FCC).
"We've always said that the FCC is going to make the determination about what is safe and what is not, but now all of a sudden, our Department of Environment is going to become the arbitrator of what is safe and what is not," he said. "All due respect to our Department of Environment, they don't have nearly the expertise that the FCC does."
Businesses should begin complying by February 2011.