San Francisco Department of the Environment

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Cell Phones

Cell phones emit radio frequency energy (radiation) when they are “on” and not just when they are in use.

There is a debate in the scientific community about the health effects of cell phone radiation. However, studies have identified evidence of health impacts such as brain cancer and reproductive damage from cell phone use. In fact, leading epidemiologists who have studied the effects of radiation absorbed from cell phones have recommended that the public be informed of the potential for adverse health effects from long-term cell phone use, particularly for children and pregnant women.

While the Federal Communications Commission (FCC) adopted a limit (measured as Specific Absorption Rate or SAR) for safe exposure to radiofrequency energy that cell phone manufacturers must meet, manufacturers warn (in the cell phone user manuals) “if a user holds a phone too close to their body, a phone may exceed the radiofrequency energy exposure limitation set by the Federal Communications Commission ("FCC").”  

Given that cell phone usage has increased steadily in the last few years, and that cell phones are being used at younger ages, scientists and advocates are recommending public outreach to increase awareness.


Tip #4: Is there a way to use my cell phone and reduce my exposure to radiofrequency energy?

Tips for Healthy Homes 


San Francisco's Cell Phone Right-to-Know Ordinance

In 2003, San Francisco became the first City in the US to adopt the Precautionary Principle, which authorizes  the government to take steps to inform the public of the potential for harm even when complete scientific certainty has not been established.

In line with the Precautionary Principle and in response to concerns about cell phone radiation, the City introduced the Cell Phone Right-to-Know (RTK) Ordinance in 2010. The goal of the ordinance was to educate the general public about steps they can take to reduce their exposure to cell phone radiation if they are concerned. The most important element of this original ordinance was the requirement for cell phone retailers to display disclosure materials (containing the only available measurement data regarding cell phone radiation i.e. the SAR values of each phone) in a format approved through a public process.

This ordinance was significantly amended in 2011 to simplify the requirement for retailers while still maintaining the intent of the original ordinance. The revised ordinance required cell phone retailers to inform customers about measures they can take to reduce their exposure to radiofrequency energy from cell phones using a posterfactsheet and display stickers.

As the City was developing regulations to implement the cell phone RTK ordinance, the World Health Organization classified cell phone radiation as “possibly carcinogenic to humans (Group 2B)” based on increased risk for glioma, a malignant type of brain cancer, associated with wireless phone use.

In 2010, CTIA filed suit challenging the "San Francisco Cell Phone Right to Know" ordinance on First Amendment and preemption grounds.  The federal district court rejected CTIA's preemption claims, and rejected the bulk of CTIA's First Amendment argument as well.  The district court ruled that, so long as the City cured certain minor defects, the First Amendment would not prevent the City from requiring retailers to provide customers with a factsheet identifying the possible health effects of cell phone radiation and describing simple measures consumers could take to minimize exposure.

In September 2012, the U.S. Court of Appeals for the Ninth Circuit reversed the district court's ruling in an unpublished opinion. The Ninth Circuit ruled that the City's disclosure requirement violated the First Amendment because a debate existed in the scientific community about the health effects of cell phone radiation, and because the FCC had determined that cell phones that fall within FCC guidelines are safe for use.

San Francisco believes the Ninth Circuit's opinion is deeply flawed, but the City is bound by that opinion, as the district court would be in further litigation over San Francisco's ordinance.  Accordingly, San Francisco settled the case with CTIA in exchange for a waiver of attorneys' fees. However, because the Ninth Circuit's decision is unpublished, it is not binding on any jurisdiction other than San Francisco, and it would not be binding on any other district court in litigation over any legislation from another jurisdiction imposing disclosure requirements on retailers. Furthermore, under the Federal Rules of Appellate Procedure, no party is permitted to cite the Ninth Circuit's unpublished opinion as precedent in future litigation.



image of mobile phones - Health Effects of Exposure to Cell Phone Radiation

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