San Francisco city leaders, after losing a key round in court against the cell phone industry, have agreed to revoke an ordinance that would have been the first in the United States to require retailers to warn consumers about potentially dangerous radiation levels. 

In a move watched by other U.S. states and cities considering similar measures, the city Board of Supervisors voted on Tuesday to settle a lawsuit with the Cellular Telecommunications Industry Association by accepting a permanent injunction against the right-to-know cell phone ordinance. 

The group had alleged the law violated its free-speech rights, and the settlement marked a victory for the industry as the Federal Communications Commission considers a reassessment of safe radiation exposure limits adopted in 1996. 

"This is just a terrible blow to public health," Ellen Marks, an advocate for the measure, said outside the supervisors' chambers. She said her husband suffers from a brain tumor on the same side of his head to which he most often held his mobile phone. 

The industry association has asserted the San Francisco ordinance, if put into effect, would mislead consumers about the relative risks posed by cell phones, contrary to the FCC's determination that all wireless phones legally sold in the Unites States are safe. 

The group's members include some of the nation's largest cell phone carriers and manufacturers, including Verizon Wireless, AT&T, Samsung and Apple. 

Deputy City Attorney Vince Chhabria said a federal appeals court decision last year upholding a preliminary injunction against the measure signaled that trying to win the case at trial would be a long shot. If the city lost, a judge could have awarded the industry group as much as $500,000 in attorneys' fees, he said. 

The 2011 ordinance mandated warnings that cellular phones, including smartphone devices, emit potentially cancer-causing radiation. The statute, which a judge blocked before it took effect, also would have required retailers of the devices to post notices stating that World Health Organization cancer experts have deemed mobile phones "possibly carcinogenic." 

Supervisor David Campos reluctantly supported the settlement. "I think the legal reality is that if we don't approve the settlement, we're talking about having to pay $500,000 in legal fees," he said. 

Chhabria said the 9th U.S. Circuit Court of Appeals ruling had left San Francisco in the position of having to prove that scientists concurred about the hazards of cell phones and that the FCC no longer believes they are safe. 

Despite mounting evidence the phones may cause brain tumors, scientists disagree and are hesitant to draw conclusions. 

Dr. Gabriel Zada, a neurosurgery professor at the University of Southern California's Keck School of Medicine, found in a 2012 study that the age-adjusted incidence of malignant tumors in the parts of the brain closest to where people hold their phones rose significantly from 1992 and 2006 in California. But Zada told Reuters he could not draw any conclusions about the dangers of cell phones from his findings. 

The Environmental Working Group, a nonprofit research organization, had pushed for San Francisco's right-to-know law. 

"If the nation's experience with tobacco taught us anything, it is that it is dangerous to wait until there is scientific consensus about a potential health threat before providing consumers with information on how they can protect themselves," said Renee Sharp, the group's research director. 

Mobile phones are tested to ensure their emissions fall within FCC limits considered safe. The limits, however, fail to reflect the latest research or actual conditions under which mobile phones are used, liked being held in a pocket directly against the body while talking through an earpiece, according to a Government Accountability Office report. 

The FCC last month agreed to consider revising its 17-year-old guidelines. 

SIMI VALLEY, Calif. -- Lingering radioactive contamination exists at a former rocket test lab outside of Los Angeles that was the site of a partial nuclear meltdown, federal environmental regulators said Wednesday.

The Environmental Protection Agency launched a $42 million study to investigate radioactive pollution at the Santa Susana Field Laboratory, 25 miles northwest of downtown Los Angeles.

Technicians collected 3,735 soil samples from a corner of the 2,850-acre hilltop lab where most of the testing was done. Of those, they found about 10 percent contained radioactive concentrations exceeding background levels.

Most of the contaminated soil was found in places like the materials handling facility that were previously cleaned, but it looked like "isolated spots were missed," said Mary Aycock, an EPA Superfund remedial project manager.

More environment coverage from NBC News

The pollution occurred in restricted areas of the lab and environmental officials said there was no immediate threat to the community because the site is secure.

The EPA presented its findings at a public meeting in Simi Valley, home of the Santa Susana Field Laboratory. It expects to issue a final report by the end of the month.

The Energy Department conducted nuclear research at the site from the 1950s through 1998. It was the site of 10 reactors, one of which had a partial meltdown, and an open-air pit where workers burned radioactive and chemical waste.

The EPA deals with Superfund sites around the United States and many former Energy Department facilities in the West are more contaminated than Santa Susana, said Michael Montgomery, assistant director of EPA's Superfund division.

The Energy Department, NASA and Boeing Co. are responsible for a cleanup that is being overseen by the state. The deadline for ridding the site of chemical and radioactive pollution is 2017.

More content from NBCNews.com:

• Oregon shopping mall gunman identified; motive unclear
• Rock legends perform at Sandy benefit show
• Cops: Dad carves pentagram into son's back on 12-12-12
• Girl, 15, shot in Oregon mall cheats death twice
• 'Unique' smuggling attempt: $42,500-worth of marijuana shot into Ariz. by cannon
• Much-criticized 'drum major' quote on Martin Luther King Jr. Memorial to be removed
• Video: Driver ticketed for truck covered in Christmas lights

Follow US news from NBCNews.com on Twitter and Facebook

A provocative new study released this week suggests as many as 14,000 Americans may have died as a result of exposure to radioactive particles blown here from Japan after the Fukushima nuclear reactor meltdown in March. But even though the report is gaining some attention, experts say there is no scientific basis for its claims. 

The study, published in the International Journal of Health Services, was based on mortality data from the Centers for Disease Control and Prevention and compared death rates before and after the cloud of radioactive air rising out of the crippled reactor hit U.S. shores.

Joseph Mangano, the lead author of the new report, says the number of deaths in the spring of 2011 was 4.46 percent higher than in the previous spring and the most likely cause was the higher levels of radiation.

Mangano also found an increase of 2.34 percent in the winter of 2011 compared to the previous year, but he called that increase “standard,” as opposed to the beginning of a trend. Mangano said he couldn’t prove that the higher than expected death rate was due to radiation, but he said he believed it was the leading contender. He was unable to point to any studies showing how low levels of radiation in the U.S. would cause death.

While U.S. deaths did rise in 2011, radiation doesn't make sense as the cause, experts say.

“There’s nothing in the radiation health effects research to substantiate those claims,” said Bernadette Burden, a spokesperson for the CDC.

Radiation expert Andrew Maidment said that the levels of radiation that blew over the U.S. were too low to have caused any deaths – especially in such a short period of time following the disaster. 

“For acute radiation sickness you would need much higher levels of radioactivity,” said Maidment, an associate professor of radiology and chief of the physics section in the department of radiology at the University of Pennsylvania. “The levels they are talking about we see naturally occurring across the country.”

What Maidment means is that normal radiation levels vary from region to region around the nation. And though the levels rose in certain areas as a result of the cloud of particles coming from the reactor, those levels still weren’t the highest measured around the U.S. so, they’re still within the norm for the U.S.

Cancers typically associated with lower levels of radiation take years to develop, Maidment explained. “With leukemia, you’re talking about five to seven years,” he said. “And there’s a 10 to 20 year delay for solid tumors. I know of no mechanism that could get you instantaneous mortality from radiation at lower levels.”

Dr. Robert L. Brent agreed. “The exposure of the USA population was extremely small and could not account for any acute lethal effects of radiation,” said Brent, a member of the National Counsel for Radiation Protection and distinguished professor of pediatrics, radiology and pathology at the Jefferson Medical College and the Dupont Hospital for Children.

"The authors indicated that SIDS (Sudden Infant Death Syndrome) was increased according to the mortality figures the authors obtained from the CDC," said Brent. "To infer that SIDS can be produced by low or high exposures to protracted radiation is naïve. That is not even a remote possibility."

So, how can you explain the rise in U.S. deaths following the reactor disaster?

There’s something called biological variability, Brent said. “For example, if you look at reports from the CDC on birth defects, you might find in a particular month a single case of Down Syndrome. The next month there might be seven. That’s biological variability.”

You can’t assume that a bump in the death rate was caused by a particular factor just because the timing was right, Brent said. “It has to be biologically plausible before you think about linking the two.”

Some associations are just the result of chance, experts said.

Maidment said it’s always possible that the events in Japan made some people in the U.S. very worried. “One thing we do know is that stress correlates with mortality,” he added. “It might be interesting to see if there was an increase in mortality after other highly stressful events, such as 9/11.”

Read more Vitals. It's good for you!

Deadly shoulder massager relaxes, strangles

Tiny listeria survivor comes home for Christmas

Maggots speedier than surgeons at wound cleaning