BERKELEY (CBS SF) — The cell phone industry is suing the city of Berkeley over an ordinance requiring retailers to attach warning labels to cell phones.

In May, Berkeley passed the nation’s first radiation warning for new cell phones, called the “right to know” law.

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The ordinance was passed unanimously.

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CTIA – The Wireless Association filed the suit Monday, alleging that “Berkeley’s Ordinance plainly violates the First Amendment,” and contradicts the determination “that cellphones approved for sale in the United States do not pose a public health risk,” in a statement released by Theodore B. Olson, one of the lawyers representing the group.

The city of San Francisco came closer on this front, approving regulations in 2010 that mandated cellphone retailers display the Specific Absorption Rate (SAR) — or the amount of radio frequency (RF) energy absorbed by the body — for each phone sold. The Cellular Telephone Industries Association immediately sued the city,claiming the law would confuse consumers by implying that lower radiation levels are safer, and the ordinance was thrown out.

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