microwavenews.com, 9 April 2018
Why Peer Review Panel and NTP Interpreted the Same Animal Data Differently
“You had it right the first time.” That was the implicit message to the National Toxicology Program (NTP) from an expert panel after a point-by-point review of NTP’s draft reports on its $25 million study of cancer risks of cell phone radiation on mice and rats.
Two years ago, with the results in hand, the NTP had rushed to warn the public about the dangers of cell phones. It issued an interim report pointing to higher rates of tumors in the hearts and brains of male rats exposed to two different kinds of phone radiation. Then early this February with the release of the formal draft reports, the NTP made a U-turn, saying that using a cell phone “is not a high-risk situation.”
Now a peer review panel —11 pathologists and toxicologists from academia and industry and one statistician— has concluded that there is “clear evidence of carcinogenic activity” in those male rats. The panel, which met* March 26-28, in Research Triangle Park, NC, determined that both GSM and CDMA signals had led to the development of a rare tumor in the hearts of rats, malignant schwannoma. The NTP, on the other hand, had concluded there was only “some evidence” for this association.
The panel saw some evidence of that same schwannoma risk among female rats, where the NTP had found only equivocal evidence.
The NTP uses five categories to classify evidence of carcinogenicity. The strongest is “clear evidence.” In decreasing order of severity, the others are: “some,” “equivocal,” “no” and “inadequate” evidence. For more details, go here.
Beyond the schwannomas in the heart, the panel members saw more evidence of a cancer risk than the NTP for tumors in two other organs of the male rats: the brain and in the adrenal gland. In both cases, the panel again raised the finding a notch, from equivocal to some evidence.
All in all, the panel upgraded seven different NTP findings, an unprecedented number. “It is highly unusual for a peer review panel to recommend so many upgrades to NTP’s conclusions,” Ron Melnick told us after the meeting. “As far as I recall, no panel has ever recommended so many, in fact, I don’t remember any at all.” Melnick led the team that designed the animal study. He retired in early 2009 after close to 30 years as a staff scientist at NTP.
In February, after NTP’s about-face, we speculated about the political forces that might have led NTP to change its outlook. The NTP presentations at the peer review meeting followed by the comments of the panelists shed light on how the two groups could look at the same tumor data and reach very different conclusions.
The panelists unanimously praised the design and execution of the NTP project. But when it came to interpreting the results, they diverged. Two factors that kept coming up over the course of the three-day meeting help explain the dynamics of their disagreement: (1) The role of the unexposed comparison animals, known as the “controls,” and (2) how RF radiation interacts with living systems. In the end, the peer reviewers were willing to accept the idea that RF radiation does not necessarily behave in the same way as the toxic chemicals that the NTP has been testing for decades.
Continue reading:
http://microwavenews.com/news-center/ntp-peer-review-sees-tumor-risk
“You had it right the first time.” That was the implicit message to the National Toxicology Program (NTP) from an expert panel after a point-by-point review of NTP’s draft reports on its $25 million study of cancer risks of cell phone radiation on mice and rats.
Two years ago, with the results in hand, the NTP had rushed to warn the public about the dangers of cell phones. It issued an interim report pointing to higher rates of tumors in the hearts and brains of male rats exposed to two different kinds of phone radiation. Then early this February with the release of the formal draft reports, the NTP made a U-turn, saying that using a cell phone “is not a high-risk situation.”
Now a peer review panel —11 pathologists and toxicologists from academia and industry and one statistician— has concluded that there is “clear evidence of carcinogenic activity” in those male rats. The panel, which met* March 26-28, in Research Triangle Park, NC, determined that both GSM and CDMA signals had led to the development of a rare tumor in the hearts of rats, malignant schwannoma. The NTP, on the other hand, had concluded there was only “some evidence” for this association.
The panel saw some evidence of that same schwannoma risk among female rats, where the NTP had found only equivocal evidence.
The NTP uses five categories to classify evidence of carcinogenicity. The strongest is “clear evidence.” In decreasing order of severity, the others are: “some,” “equivocal,” “no” and “inadequate” evidence. For more details, go here.
Beyond the schwannomas in the heart, the panel members saw more evidence of a cancer risk than the NTP for tumors in two other organs of the male rats: the brain and in the adrenal gland. In both cases, the panel again raised the finding a notch, from equivocal to some evidence.
All in all, the panel upgraded seven different NTP findings, an unprecedented number. “It is highly unusual for a peer review panel to recommend so many upgrades to NTP’s conclusions,” Ron Melnick told us after the meeting. “As far as I recall, no panel has ever recommended so many, in fact, I don’t remember any at all.” Melnick led the team that designed the animal study. He retired in early 2009 after close to 30 years as a staff scientist at NTP.
In February, after NTP’s about-face, we speculated about the political forces that might have led NTP to change its outlook. The NTP presentations at the peer review meeting followed by the comments of the panelists shed light on how the two groups could look at the same tumor data and reach very different conclusions.
The panelists unanimously praised the design and execution of the NTP project. But when it came to interpreting the results, they diverged. Two factors that kept coming up over the course of the three-day meeting help explain the dynamics of their disagreement: (1) The role of the unexposed comparison animals, known as the “controls,” and (2) how RF radiation interacts with living systems. In the end, the peer reviewers were willing to accept the idea that RF radiation does not necessarily behave in the same way as the toxic chemicals that the NTP has been testing for decades.
Continue reading:
http://microwavenews.com/news-center/ntp-peer-review-sees-tumor-risk
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