Showing posts with label cell phone use. Show all posts

Thursday, February 1, 2024

The Incidence of Meningioma, a Non-Malignant Brain Tumor, is Increasing in the U.S.

In the U.S. nonmalignant meningioma, a non-malignant tumor on the outer covering of the brain, is the most common brain tumor.

Since the year 2000, the U.S. has experienced significant increases in the age-adjusted incidence rates of meningioma along with three other head and neck tumors.

Whereas the size of the population in the U.S. increased 16% between 2000 and 2019, the number of cases reported in the National Cancer Institute's SEER 22 registry for this tumor increased 124%.

The overall age-adjusted incidence rate for nonmalignant meningioma of the brain and nervous system significantly increased 70% in the U.S. from 2004 (6.46 per 100,000) to 2019 (11.01 per 100,000). From 2004 to 2008, the increase was 12.3% per year, and from 2008 to 2019, the increase was 2.1% per year.

Among youth less than 20 years of age the incidence of nonmalignant meningioma significantly increased by 2.8% per year from 2004 to 2019.

The increase in age-adjusted incidence rate for this tumor is likely attributable to the chronic effects of mobile phone use in addition to other factors including improvements in screening. The incidence of this tumor was not reported to the SEER registry prior to 2004.

The tumor incidence rate data are from the SEER 22 Registry which covers 48% of the total U.S. population. The data were age-adjusted to the population in the year 2000 so observed differences over time are not affected by changes in the age composition of the population.

https://seer.cancer.gov/statistics-network/explorer/application.html?site=501&data_type=1&graph_type=2&compareBy=age_range&chk_age_range_1=1&chk_age_range_16=16&chk_age_range_62=62&chk_age_range_122=122&chk_age_range_160=160&chk_age_range_166=166&chk_age_range_15=15&hdn_rate_type=1&sex=1&race=1&hdn_stage=101&advopt_precision=2&advopt_show_ci=on&hdn_view=1&advopt_show_apc=on&advopt_display=2#resultsRegion1

Reference: SEER*Explorer: An interactive website for SEER cancer statistics [Internet]. Surveillance Research Program, National Cancer Institute; 2023 Apr 19. [updated: 2023 Nov 16; cited 2024 Jan 9]. Available from: https://seer.cancer.gov/statistics-network/explorer/. Data source(s): SEER Incidence Data, November 2022 Submission (1975-2020), SEER 22 registries.

March 15, 2023

http://bit.ly/3Tjzxxx

March 15, 2023 (Updated March 18, 2023)

It is tricky trying to interpret the results of ecological studies (studies used to understand the relationship between outcome and exposure at a population level, where 'population' represents a group of individuals with a shared characteristic):

(1) it is difficult to control for confounding,

(2) associations may be due to chance, and

(3) population-level associations may not correspond to processes that occur at the individual-level (i.e., ecological fallacy).

The risk factors underlying changes over time in tumor incidence in the population can be difficult to identify if there were changes in screening and diagnostic procedures or changes in reporting practices.

Moon (2023) recently reported that the age-standardized incidence rate of nonmalignant meningioma (D32) increased from 1999 to 2018 [Average Annual Percent Change =36.69% (95% CI = 33.53–39.85)] in South Korea. The rate increased from 2.08 per 100,000 in 2004 to 7.07 per 100,000 in 2018 (see Supplementary Material B).

Keeping the caveats mentioned above in mind about ecological studies, it is intriguing that Moon (2023) reported that the correlation of the age-standardized incidence rate of nonmalignant meningioma with the cell phone subscription rate ten years earlier in South Korea was very high (r = .92, 95% CI = .80 - .97). This result suggests that cell phone use in the population could be contributing to the development of nonmalignant tumors of the meninges, the tissue covering the outer portion of the brain, ten years later.

In the U.S., based on SEER 22 Areas tumor registry data, the age-standardized incidence rate of nonmalignant meningioma increased from 6.4 per 100,000 in 2004 (the first year this tumor was reported by SEER) to 10.1 per 100,000 in 2018 (see Figure above).

Based upon my calculation, in the U.S. the correlation of age-standardized incidence rates of nonmalignant meningioma (from 2004-2018 in SEER 22) with cell phone subscription rates in the U.S. ten years earlier (from 1994-2008 as reported in Supplementary Material B in Moon, 2023) was also very high (r=.89, 95% CI =.70 - .96).

Case-control studies provide stronger evidence of this risk factor. Although not all case-control studies have found an association between heavy wireless phone use and meningioma, at least three studies reported significant associations:

In Sweden, Carlberg and Hardell (2015) found that heavy use of wireless phones (i.e., cell phones and cordless phones) was associated with greater risk of meningioma. Heavy cordless phone users (defined as more than 1,436 hours of lifetime use) had a 1.7-fold greater risk of meningioma (OR = 1.7; 95% CI = 1.3-2.2). The heaviest cordless phone users (defined as more than 3,358 hours of lifetime use) had a two-fold greater risk of meningioma (OR = 2.0; 95% CI = 1.4 - 2.8). The heaviest cell phone users had a 1.5-fold greater risk of meningioma (OR = 1.5, 95% CI = 0.99 - 2.1).

In France, Coureau et al. (2014) found a two and a half-fold greater risk of meningioma for heavy cell phone users (defined as 896 or more hours of lifetime use) (OR = 2.57; 95% CI = 1.02 to 6.44).

Using data from Australia, Canada, France, Israel and New Zealand, Cardis et al. (2011) found a two-fold greater risk of meningioma for heavy cell phone users (defined as 3,124 or more hours of lifetime use) (OR = 2.01; 95% CI = 1.03 to 2.93).

In sum, use of wireless phones over a ten-year period, including cell phone and cordless phone use, may contribute to the development of nonmalignant meningioma in the U.S. as well as other countries.

Wednesday, July 1, 2020

American Cancer Society: Cell Phone Radiation Risk

"The American Cancer Society (ACS) does not have any official position or statement on whether or not radiofrequency (RF) radiation from cell phones, cell phone towers, or other sources is a cause of cancer. ACS generally looks to other expert organizations to determine if something causes cancer (that is, if it is a carcinogen), including:

The International Agency for Research on Cancer (IARC), which is part of the World Health Organization (WHO)
The US National Toxicology Program (NTP), which is formed from parts of several different government agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA)

Other major organizations also sometimes comment on the ability of certain exposures (such as cell phone use) to cause cancer."

https://www.cancer.org/cancer/cancer-causes/radiation-exposure/cellular-phones.html

Why has the American Cancer Society relied on advice from the International Commission on Non-Ionizing Radiation Protection (ICNIRP), a self-selected group of scientists, many of whose members have conflicts of interest? Why does the Society ignore the advice of its former chief medical director, Otis W. Brawley, M.D. regarding the NTP study (see 2016 ACS press release below.)

Cellular (Cell) Phones

American Cancer Society, Revised June 1, 2020

Cellular (cell or mobile) phones first became widely available in the United States in the 1990s. Since then, along with the large and still growing number of cell phone users (both adults and children), the amount of time people spend on their phones has also risen sharply.

Cell phones give off a form of energy known as radiofrequency (RF) waves, so the safety of cell phone use has raised some concerns. The main concerns have focused on whether cell phones might increase the risk of brain tumors or other tumors in the head and neck area, as these areas are closest to where the phone is usually held while talking or listening on a call.

How do cell phones work?

Cell phones send signals to (and receive them from) nearby cell towers (base stations) using RF waves. This is a form of energy in the electromagnetic spectrum that falls between FM radio waves and microwaves. Like FM radio waves, microwaves, visible light, and heat, RF waves are a form of non-ionizing radiation. They don’t have enough energy to cause cancer by directly damaging the DNA (genes) inside cells. RF waves are different from stronger (ionizing) types of radiation such as x-rays, gamma rays, and ultraviolet (UV) rays. Ionizing radiation can break the chemical bonds in DNA, which might lead to cancer.

The electromagnetic spectrum illustration shows the possible frequencies of electromagnetic energy, ranging from extremely low frequencies (such as those from power lines) to exposures from extremely high frequencies (x-rays and gamma rays), and includes both non-ionizing and ionizing radiation.

Image credit: National Cancer Institute

At very high levels, RF waves can heat up body tissues. But the levels of energy given off by cell phones are much lower, and are not enough to raise temperatures in the body.

How are people exposed?

The RF waves come from the cell phone's antenna, which is part of the body of a hand-held phone. The waves are strongest at the antenna and lose energy quickly as they travel away from the phone. The phone is often held against the head when a person is on a call. The closer the antenna is to a user's head, the greater their expected exposure to RF waves. The body tissues closest to the phone absorb more energy from RF waves than tissues farther away.

Many factors can affect the amount of energy from RF waves that a person is exposed to, including:

The amount of time the person is on the phone.
Whether the person is holding the phone close to the head, or is instead using the speaker mode or a hands-free device. The farther away from a person's body the phone is, the less they are exposed.
The distance and path to the nearest cell phone tower. Cell phones adjust their power to use the minimum amount for a good signal. Being farther away from the tower requires more energy to get a good signal, as does being inside a building.
The amount of cell phone traffic in the area at the time. Higher traffic (from many people using cell phones) may require more energy to get a good signal.
The model of phone being used. Different phones give off different amounts of energy.

Cell phone specific absorption rate (SAR)

The specific absorption rate (SAR) is the amount of RF energy from the phone absorbed by the user’s body. Different cell phones have different SAR levels. Cell phone makers are required to report the maximum SAR level of their product to the US Federal Communications Commission (FCC). This information can often be found on the manufacturer’s website or in the user manual for the phone. The upper limit of SAR allowed in the United States according to FCC safety guidelines is 1.6 watts per kilogram (W/kg) of body weight.

But according to the FCC, comparing SAR values between phones can be misleading. The listed SAR value is based only on the phone operating at its highest power, not on what users would typically be exposed to with normal phone use. The actual SAR during use varies based on a number of factors, so it’s possible that a phone with a lower listed SAR value might sometimes expose a person to more energy from RF waves than one with a higher listed SAR value.

Do cell phones cause tumors?

Because cell phones usually are held near the head when a person is on a call, the main concern has been whether the phones might cause or contribute to tumors in this area, including:

Malignant (cancerous) brain tumors, such as gliomas
Non-cancerous tumors of the brain, such as meningiomas
Non-cancerous tumors of the nerve connecting the brain to the ear (vestibular schwannomas, also known as acoustic neuromas)
Tumors of the salivary glands

A few studies have also looked at possible links to other types of cancer.

What do studies show?

Researchers use 2 main types of studies to try to determine if something might cause cancer:

Studies done in the lab (using lab animals or cell cultures)
Studies looking at groups of people

In most cases neither type of study provides enough evidence on its own to show if something causes cancer in people, so researchers usually look at both lab-based and human studies.

The following is a brief summary of some of the major studies that have looked at this issue to date. However, this is not a comprehensive review of all studies that have been done.

Lab studies of RF waves

As noted above, the RF waves given off by cell phones don’t have enough energy to damage DNA directly or to heat body tissues. Because of this, it’s not clear how cell phones might be able to cause cancer. Some studies have found possible increased rates of certain types of tumors in lab animals exposed to RF radiation, but overall, the results of these types of studies have not provided clear answers so far.

Large studies published in 2018 by the US National Toxicology Program (NTP) and by the Ramazzini Institute in Italy exposed groups of lab rats (as well as mice, in the case of the NTP study) to RF waves over their entire bodies for many hours a day, starting before birth and continuing for most or all of their natural lives. Both studies found an increased risk of uncommon heart tumors called malignant schwannomas in male rats, but not in female rats (nor in male or female mice, in the NTP study). The NTP study also reported possible increased risks of certain types of tumors in the brain and in the adrenal glands.

While both of these studies had strengths, they also had limitations that make it hard to know how they might apply to humans being exposed to RF waves from cell phones. A 2019 review of these two studies by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) determined that the limitations of the studies didn’t allow conclusions to be drawn regarding the ability of RF energy to cause cancer.

Still, the results of these studies do not rule out the possibility that RF waves from cell phones might somehow impact human health.

Studies in people

Several dozen studies have looked at possible links between cell phone use and tumors. Most of these studies have focused on brain tumors. Many of these have been case-control studies, in which patients with brain tumors (cases) were compared to people who didn't have brain tumors (controls), in terms of their past cell phone use.

These studies have had mixed results. Some studies have found a possible link between cell phone use and brain tumors, while others have not. For example, several studies published by the same research group in Sweden have reported an increased risk of brain tumors in people using cell phones. However, there was no apparent overall increase in brain tumors in Sweden during the years that correspond to these reports.

Three large studies deserve special mention:

The INTERPHONE study

The 13-country INTERPHONE study, the largest case-control study done to date, looked at cell phone use among more than 5,000 people who developed brain tumors (gliomas or meningiomas) and a similar group of people without tumors. Overall, the study found no link between brain tumor risk and the frequency of calls, longer call time, or cell phone use for 10 or more years. There was a suggestion of a possible increased risk of glioma, and a smaller suggestion of an increased risk of meningioma, in the 10% of people who used their cell phones the most. But this finding was hard to interpret because some people in the study reported implausibly high cell phone use. The researchers noted that the shortcomings of the study prevented them from drawing any firm conclusions, and that more research was needed.

Another part of the INTERPHONE study compared more than 1,000 people with acoustic neuromas to more than 2,000 people without tumors, who served as matched controls. As with gliomas and meningiomas, there was no overall link between cell phone use and acoustic neuromas. There was again a suggestion of a possible increased risk in the 10% of people who used their cell phones the most, but this finding was hard to interpret because some people reported implausibly high cell phone use.

The Danish cohort study

A large, long-term study has been comparing all of the people in Denmark who had a cell phone subscription between 1982 and 1995 (about 400,000 people) to those without a subscription to look for a possible increase in brain tumors. The most recent update of the study followed people through 2007. Cell phone use, even for more than 13 years, was not linked with an increased risk of brain tumors, salivary gland tumors, or cancer overall, nor was there a link with any brain tumor subtypes or with tumors in any location within the brain.

This type of study (following a large group of people going forward in time and not relying on people’s memories about cell phone use) is generally thought to provide stronger evidence than a case-control study.

But this study also has some drawbacks. First, it is based only on whether or not people had a cell phone subscription at the time. It didn’t measure how often these people used their phones (if at all), or if people who didn’t have a subscription used someone else’s phone. There are also limits as to how well this study might apply to people using cell phones today. For example, while the cell phones used at the time of the study tended to emit higher levels of RF waves than modern cell phones do, people also probably used their phones quite a bit less than people use their phones today.

The Million Women Study

A large prospective (forward-looking) study of nearly 800,000 women in the UK examined the risk of developing brain tumors over a 7-year period in relation to self-reported cell phone use at the start of the study. This study found no link between cell phone use and brain tumors overall or several common brain tumor subtypes, but it did find a possible link between long-term cell phone use and acoustic neuromas. The authors of this study, however, did note the possibility that this link might have been due to more intensive medical investigation in long-term cell phone users because of media coverage at the time.

All studies done so far have limitations

In summary, studies of people published so far have not established a clear link between cell phone use and the development of tumors. However, these studies have had some important limitations that make them unlikely to end the controversy about whether cell phone use affects cancer risk.

First, studies have not yet been able to follow people for very long periods of time. After a known cancer-causing exposure, it often takes decades for tumors to develop. Because cell phones have been widely used for only about 20 years in most countries, it is not possible to rule out possible future health effects.

Second, cell phone usage is constantly changing. People are using their cell phones much more than they were even 10 years ago, and the phones themselves are very different from what was used in the past. This makes it hard to know if the results of studies looking at cell phone use in years past still apply today.

Third, most of the studies published so far have focused on adults, rather than children. (One case-control study looking at children and teens did not find a significant link to brain tumors, but the small size of the study limited its power to detect modest risks.) Cell phone use is now widespread even among younger children. It is possible that if there are health effects, they might be more pronounced in children because their bodies might be more sensitive to RF energy. Another concern is that children’s lifetime exposure to RF waves from cell phones will be greater than adults’, who started using cell phones when they were older.

Finally, the measurement of cell phone use in most studies has been crude. Most have been case-control studies, which have relied on people’s memories about their past cell phone use. In these types of studies, it can be hard to interpret any possible link between cancer and an exposure. People with cancer are often thinking about possible reasons for it, so they may sometimes recall their phone usage differently from people without cancer.

With these limitations in mind, it is important to continue to study the possible risk of cell phone exposure, especially with regard to use by children and longer-term use.

What do expert agencies say?

The American Cancer Society (ACS) does not have any official position or statement on whether or not radiofrequency (RF) radiation from cell phones, cell phone towers, or other sources is a cause of cancer. ACS generally looks to other expert organizations to determine if something causes cancer (that is, if it is a carcinogen), including:

The International Agency for Research on Cancer (IARC), which is part of the World Health Organization (WHO)
The US National Toxicology Program (NTP), which is formed from parts of several different government agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA)

Other major organizations also sometimes comment on the ability of certain exposures (such as cell phone use) to cause cancer.

Based on a review of studies published up until 2011, the International Agency for Research on Cancer (IARC) has classified RF radiation as “possibly carcinogenic to humans,” based on limited evidence of a possible increase in risk for brain tumors among cell phone users, and inadequate evidence for other types of cancer. (For more information on the IARC classification system, see Known and Probable Human Carcinogens.)

More recently, the US Food and Drug Administration (FDA) issued a technical report based on studies published between 2008 and 2018, as well as national trends in cancer rates. The report concluded: “Based on the studies that are described in detail in this report, there is insufficient evidence to support a causal association between radiofrequency radiation (RFR) exposure and [tumor formation].”

So far, the National Toxicology Program (NTP) has not included RF radiation in its Report on Carcinogens, which lists exposures that are known to be or reasonably anticipated to be human carcinogens. (For more on this report, see Known and Probable Human Carcinogens.)

According to the US Federal Communications Commission (FCC):

“[C]urrently no scientific evidence establishes a causal link between wireless device use and cancer or other illnesses. Those evaluating the potential risks of using wireless devices agree that more and longer-term studies should explore whether there is a better basis for RF safety standards than is currently used.”

According to the US Centers for Disease Control and Prevention (CDC):

“At this time we do not have the science to link health problems to cell phone use. Scientific studies are underway to determine whether cell phone use may cause health effects.”

How can I lower my exposure to RF waves from cell phones?

It is not clear at this time that RF waves from cell phones cause harmful health effects in people, but studies now being done should give a clearer picture of the possible health effects in the future. Until more is known, there are several things that people who are concerned about RF waves can do to limit their exposure.

Use the speaker mode or video chat feature on the phone, or a hands-free device such as a corded or cordless earpiece. This moves the antenna away from your head, which decreases the amount of RF waves that reach the head. Corded earpieces emit virtually no RF waves (although the phone itself still emits small amounts of RF waves that can reach parts of the body if close enough, such as on the waist or in a pocket). Bluetooth^® earpieces typically transmit RF waves at much lower power levels than cell phones themselves (see below).

Texting instead of talking on the phone may be another way to reduce your exposure. But it may not be a good option in some situations, especially if you are driving. For safety reasons, it is especially important to limit or avoid the use of cell phones (especially texting) while driving.

Limit your (and your children’s) cell phone use. This is one of the most obvious ways to limit your exposure to RF waves from cell phones. For example, you may want to limit the amount of time you spend talking on the phone (at least with your phone up to your ear). Parents who are concerned about their children’s exposure can limit how much time they spend talking on the phone.

Consider choosing a phone with a low SAR value. Different models of phones can give off different levels of RF waves. But as noted above, according to the FCC the SAR value is not always a good indicator of a person’s exposure to RF waves during normal cell phone use. One way to get information on the SAR level for a specific phone model is to visit the phone maker’s website. The FCC has links to some of these sites. If you know the FCC identification (ID) number for your phone model (which can often be found somewhere on the phone or in the user manual), you can also go to the following web address: www.fcc.gov/oet/ea/fccid. On this page, you will see instructions for entering the FCC ID number.

Are phones on 5G networks any different?

Fifth generation (5G) cellular networks are now being rolled out in many parts of the United States and in other countries. 5G networks are capable of transmitting much larger amounts of data over shorter periods of time than previous generations (4G, 3G, etc.).

5G networks (and the phones that use them) operate on some higher frequency (higher energy) RF wavelengths than older generation networks (although newer phones can typically still use the older networks as well). But the newer 5G signals still use RF waves, so they are still forms of non-ionizing radiation, which is not thought to have the ability to directly damage DNA.

The studies that have been done so far to look at possible links between cell phone use and cancer have focused on older generation (mainly 2G and 3G) signals. At this time, there has been very little research showing that the RF waves used in 5G networks are any more (or less) of a concern than the other RF wavelengths used in cellular communication. For more on 5G networks, see Cell Phone Towers.

What about cordless phones?

Cordless phones, commonly used in homes, have base units that are plugged into telephone jacks and wired to a local telephone service. They are not considered cell phones. Cordless phones operate at about 1/600 the power of cell phones, so they are much less likely to be a concern in terms of health effects.

What about Bluetooth^® devices (including earbuds)?

Many wireless devices now communicate over shorter distances using Bluetooth technology. For example, many phones now have the option of using wireless (Bluetooth) earbuds. Phones can also connect to other devices (tablets, laptops, car dashboard computers, etc.) using Bluetooth.

Bluetooth devices use RF waves in a similar wavelength range as those used for cell phones. But because the signals only need to travel a short distance (such as from the phone to a person’s ears), they can operate at much lower power levels than those used by phones, which in theory might make them less of a health concern. But as with other devices that give off RF waves, possible health effects from these devices cannot be ruled out completely at this time.

https://www.cancer.org/cancer/cancer-causes/radiation-exposure/cellular-phones.html

ACS Responds to New Study Linking Cell Phone Radiation to Cancer

Press Release, American Cancer Society, May 27, 2016

The U.S. National Toxicology Program (NTP) has released partial results from an animal study of the effect of radiofrequency radiation associated with cell phones. The group found radiofrequency radiation was linked to a higher risk of two cancers. Below is a response from Otis W. Brawley, M.D., American Cancer Society Chief Medical Officer.

“For years, the understanding of the potential risk of radiation from cell phones has been hampered by a lack of good science. This report from the National Toxicology Program (NTP) is good science.

“The NTP report linking radiofrequency radiation (RFR) to two types of cancer marks a paradigm shift in our understanding of radiation and cancer risk. The findings are unexpected; we wouldn’t reasonably expect non-ionizing radiation to cause these tumors. This is a striking example of why serious study is so important in evaluating cancer risk. It’s interesting to note that early studies on the link between lung cancer and smoking had similar resistance, since theoretical arguments at the time suggested that there could not be a link.

“The new report covers only partial findings from the study, but importantly one of the two cancers linked to cell phone radiation was malignant gliomas in the brain. The association with gliomas and acoustic neuromas had been suspected from human epidemiology studies. The second cancer, called a schwannoma, is an extremely rare tumor in humans and animals, reducing the possibility that this is a chance finding. And importantly, the study found a ‘dose/response’ effect: the higher the dose, the larger the effect, a key sign that this association may be real.

“The fact that this finding was observed only in male rats has some wondering if the data is not reliable. It’s important to note that these sorts of gender differences often appear in carcinogenic studies, so the fact they show up here should not detract from the importance of the findings.

“This new evidence will undoubtedly factor into ongoing assessments by regulators to determine the potential cancer risk posed by cell phones. The American Cancer Society eagerly awaits guidance from government agencies, like the U.S. Food and Drug Administration (FDA) and the Federal Communications Commission (FCC), about the safety of cell phone use.

“The NTP was given the difficult task of trying to answer important questions about the potential cancer risk posed by cell phones, and the group did not shirk from its responsibility. NTP staff were clearly aware of the potential importance of this study and went the extra distance to ensure the best science is used. They used double the number of animals required for this type of study; they convened not one but three panels to look at abnormal tissues from treated animals to ensure that what was identified as a brain and heart tumor was indeed a brain and heart tumor; they solicited review from multiple scientists from outside the NTP to critically review all aspects of the data analysis and study findings, to ensure the findings would stand up to the critical assessment expected once these unexpected findings were released.

“While this study adds significantly to the evidence that cell phone signals could potentially impact human health, it does not actually tell us how certain scenarios of cell phone use change our long-term risks of getting cancer. For example, the animal studies were performed at very high signal strengths, near but below levels that would cause animal tissue to heat up. Additional research will be needed to translate effects at these high doses to what might be expected at the much lower doses received by typical or even high-end cell phone users. Also, cell phone technology continues to evolve, and with each new generation, transmission strengths have declined and with it radio frequency exposures.”

https://acspressroom.wordpress.com/2016/05/27/ntpcellphones/

January 13, 2015

The American Cancer Society (ACS) recently revised a 58-page document entitled, “Brain and Spinal Cord Tumors in Adults” and updated its website page on “Cellular Phones.”

Brain and Spinal Cord Tumors in Adults

“Brain and Spinal Cord Tumors in Adults” dismisses the potential cancer risk from using cell phones and refers readers to the ACS web site for further information:

Cell phone use

"This has been the subject of a great deal of debate in recent years. Cell phones give off radiofrequency (RF) rays, a form of energy on the electromagnetic spectrum between FM radio waves and those used in microwave ovens, radar, and satellite stations. Cell phones do not give off ionizing radiation, the type that can cause cancer by damaging the DNA inside cells. Still, there have been concerns that the phones, whose antennae are built-in and therefore are placed close to the head when being used, might somehow raise the risk of brain tumors.

Some studies have suggested a possible increased risk of brain tumors or of vestibular schwannomas with cell phone use, but most of the larger studies done so far have not found an increased risk, either overall or among specific types of tumors. Still, there are very few studies of long-term use (10 years or more), and cell phones haven’t been around long enough to determine the possible risks of lifetime use. The same is true of any possible higher risks in children, who are increasingly using cell phones. Cell phone technology also continues to change, and it’s not clear how this might affect any risk.

These risks are being studied, but it will probably be many years before firm conclusions can be made. In the meantime, for people concerned about the possible risks, there are ways to lower your exposure, such as using an earpiece to move the phone itself away from the head. For more information, see our document Cellular Phones." (p. 15)

Can brain and spinal cord tumors in adults be prevented?

"The risk of many cancers in adults can be reduced with certain lifestyle changes (such as staying at a healthy weight or quitting smoking). But other than radiation exposure, there are no known lifestyle-related or environmental causes of brain and spinal cord tumors, so at this time there is no known way to protect against most of these tumors." (p. 17) http://bit.ly/1y8vS9B.

Cellular Phones

The ACS web site reviews the research on cell phone radiation and downplays the cancer risk from long-term exposure to cell phone and cordless phone radiation.

Although the ACS seems skeptical there is any cancer risk from cell phone use, they recommend "several things that people who are concerned about RF [radio frequency] waves can do to limit their exposure":

"Use the speaker mode on the phone or a hands-free device such as a corded or cordless earpiece. This moves the antenna away from your head, which decreases the amount of RF waves that reach the head. Corded earpieces emit virtually no RF waves (although the phone itself still emits small amounts of RF waves that can reach parts of the body if close enough, such as on the waist or in a pocket). Bluetooth^® earpieces have an SAR value of around 0.001 watts/kg (less than one thousandth the SAR limit for cell phones as set by the FDA and FCC).

Texting instead of talking on the phone may be another option to reduce your exposure. But it may not be a good option in some situations, especially if you are driving. For safety reasons, it is especially important to limit or avoid the use of cell phones while driving.

Limit your (and your children’s) cell phone use. This is one of the most obvious ways to limit your exposure to RF waves from cell phones. You may want to use your cell phone only for shorter conversations, or use it only when a conventional phone is not available. Parents who are concerned about their children’s exposure can limit how much time they spend on the phone.

Some people might consider choosing a phone with a low SAR value. Different models of phones can give off different levels of RF waves. But as noted above, according to the FCC the SAR value is not always a good indicator of a person’s exposure to RF waves during normal cell phone use. One way to get information on the SAR level for a specific phone model is to visit the phone maker’s website. The FCC has links to some of these sites here: www.fcc.gov/encyclopedia/specific-absorption-rate-sar-cellular-telephones. If you know the FCC identification (ID) number for a phone model (which can often be found somewhere on the phone or in the user manual), you can also go to the following web address: www.fcc.gov/oet/ea/fccid. On this page, you will see instructions for entering the FCC ID number.” http://bit.ly/1z7mZNm

After reviewing and dismissing the growing body of scientific evidence which finds that long-term cell phone phone use is associated with increased brain cancer risk, the ACS makes the following recommendation:

"With these limitations in mind, it is important that the possible risk of cell phone exposure continue to be researched using strong study methods, especially with regard to use by children and longer-term use." http://bit.ly/1z7mZNm

Since virtually everyone in the U.S. uses a cell phone and all are exposed to cell phone radiation, one might wonder what the ACS has done to ensure that there is adequate funding for strong research on the cancer risk. Has the ACS devoted any research funding to the study of this environmental risk? Has the ACS used its influence to ensure that Federal agencies prioritize health and safety research regarding this risk?

Sources

American Cancer Society. Brain and Spinal Cord Tumors in Adults. Last revised Jan 7, 2015. URL: http://bit.ly/1y8vS9B.

American Cancer Society. Cellular Phones. Last revised Dec 12, 2014. URL: http://bit.ly/1z7mZNm.

Monday, June 8, 2020

Cellphone use may be harmful for people with dental braces

Electric Field and SAR Distribution in the Vicinity of Orthodontic Brace Exposed to the Cell Phone Radiation

Jovanovic DB, Krasic DD, Stankovic VB, Cvetkovic, NN, Vuckovic DD. Electric Field and SAR Distribution in the Vicinity of Orthodontic Brace Exposed to the Cell Phone Radiation. Applied Computational Electromagnetics Society Journal 34(12):1904-1914. Dec 2019.

Abstract

The aim of this study is to investigate the impact of orthodontic brace on the electric field distribution and amount of the absorbed energy from the cell phone within the teeth. A comparative analysis of the models (child and adult) with and without brace has been carried out due to different morphological and tissue characteristics of child's and adult's head. The 3D realistic models of the child's and adult's head, with the jaw having the orthodontic brace, have been designed. The shapes and features of the child and adult head model, as well as the distance between the electromagnetic source and the exposed object, have an important role in the evaluation of the Specific Absorption Rate (SAR). The applied procedure is based on the numerical solution of the electromagnetic waves propagation equations. The numerical analysis has been performed at the frequency of 3G (0.9GHz). The obtained results are represented within the teeth positioned on the side of the electromagnetic radiation source. Based on the obtained results, one can conclude that the presence of orthodontic brace affects the increase of electric field and SAR within the teeth.

Excerpts

"According to previous studies, one can find that the metal objects can significantly increase the amount of absorbed energy. The authors in [1] have found that the SAR values can be several times greater in the presence of metal object. The effect of electromagnetic radiation from mobile phone on nickel release from orthodontic brackets has been taken into consideration in study [2]. It is found that the concentration of nickel in the artificial saliva in the exposure group was significantly higher than that of the control group. The level of the nickel released in this investigation was far below the toxic level but maybe enough that can lead to allergic reaction in humans. One of the previously studies [3] reported the involuntary movements of the subjects, which had gold (metal) alloy dental inlay, caused by electromagnetic waves."

"It is evident that the value of the electric field is significantly greater in the presence of an orthodontic brace for both models. Based on the results shown in Figs. 6-8, as well as the results given in Table 3, the overall conclusion is that the presence of an orthodontic brace increases the electric field strength within the teeth.

Also it is noticeable that the electric field strength in the case of a child is higher comparing to the adult case."

"Since the referent value for the electric field, prescribed by adequate standards at 0.9 GHz, is 41 V/m, comparing the results obtained by numerical calculation with values prescribed by safety standards, it is evident that obtained results exceed the referent levels inside all teeth in both models (with and without the orthodontic brace). However, it should be kept in mind that in the case of model with orthodontic brace the values are many times greater than the allowable values."

"Regarding the obtained results for SAR within the teeth, in the presence of an orthodontic brace, a significant increase in the amount of absorbed energy can be observed. The maximum of SAR1g occurs in the tooth No. 6 in the case of a child (2.46 W/kg). This value is about 65% higher comparing to the adult with orthodontic brace and 45% higher comparing to the results obtained for a child without orthodontic brace. In this tooth and tooth No. 5, the SAR1g overcomes the safety values but only in the case of child in the presence of the orthodontic brace. The amount of absorbed energy inside the other teeth satisfies basic restriction. However, the increase in the amount of absorbed energy in the presence of an orthodontic brace is not negligible."

"Based on the obtained results, one can conclude that the presence of orthodontic brace causes increase of electric field and SAR within the teeth. In some cases, those values overcome referent limits for electric field strength, i.e., safety limits for SAR values."

"Because of the mentioned before and the fact that each standard contains specific safety limits of exposure to electromagnetic fields but they have been developed based on the research for adults, it should be established if they are sufficiently valid also in case of children.

The future researches should be focused on the impact of orthodontic brace on the electric field strength and amount of absorbed energy at the frequency of LTE-4G, and the latest generation of mobile networks – 5G."

Open access paper: https://aces-society.org/includes/downloadpaper.php?of=ACES_Journal_December_2019_Paper_17&nf=19-12-17

Note: The FCC radio frequency radiation exposure limit (i.e., SAR1g) for cell phones is 1.6 W/kg.

--

August 3, 2015

A new peer-reviewed study found that cell phone use significantly increased nickel concentration in the saliva of 50 adult patients who wore dental braces (i.e., fixed orthodontic appliances) as compared to when they did not use their cell phones for a week. Moreover, patients who spoke more on their cell phone had a greater increase in salivary nickel concentration.

The “adverse effect of radiation on the release of nickel was more prominent in women” because they spoke more on their cell phones. The females averaged 53 minutes during the week they used their cell phones whereas the males averaged 23 minutes.

Nickel is a known toxic and carcinogenic metal. It is also a common cause of metal-induced contact allergic dermatitis. Nickel-containing alloys are often used in orthodontics for metallic brackets, arch wires, and bands.

Previous research either found no increase in salivary nickel concentration after a fixed orthodontic appliance was inserted or a significant increase that tapered off within three weeks after insertion. The patients in the current study had orthodontic appliances for 2-4 months before they participated to control for this potential confounding effect of time.

The Federal Communications Commission (FCC) requires all cell phone models be tested for their Specific Absorption Rate (SAR), a measure of the maximum amount of microwave radiation absorbed by the head and the body. SAR is measured in a laboratory using an artificial model of a large adult male with different fluids to simulate human tissue. The SAR testing procedure, adopted in 1996, was criticized by the Government Accountability Office in 2012 because it does not simulate today’s typical user or the way cell phones are typically used. The artificial head does not contain any metal (e.g., dental fillings, dental braces, metallic earrings or eyeglass frames) which could increase the radiation absorption beyond that measured in the laboratory. The artificial body test makes the unrealistic assumption that consumers will carry their cell phones in manufacturer-approved holders that keeps the phones a minimum distance away from their bodies.

Today many children are cell phone users. The young child’s brain absorbs twice the radiation as the adult’s brain. The SAR testing procedure does not take this into account.

Although the current study was conducted on young adults who had fixed orthodontic appliances, the results should have relevance for children who are more likely to be fitted for dental braces than adults.

The paper did not describe the specific types of fixed orthodontic appliances the patients had.

The abstract for the study and excerpts from the paper appear below.

Saghiri MA, Orangi J, Asatourian A, Mehriar P, Sheibani N. Effect of mobile phone use on metal ion release from fixed orthodontic appliances. Am J Orthod Dentofacial Orthop. 2015 Jun;147(6):719-24. doi: 10.1016/j.ajodo.2015.01.023.

Abstract

INTRODUCTION: The aim of this study was to evaluate the effect of exposure to radiofrequency electromagnetic fields emitted by mobile phones on the level of nickel in saliva.

METHODS: Fifty healthy patients with fixed orthodontic appliances were asked not to use their cell phones for a week, and their saliva samples were taken at the end of the week (control group). The patients recorded their time of mobile phone usage during the next week and returned for a second saliva collection (experimental group). Samples at both times were taken between 8:00 and 10:00 pm, and the nickel levels were measured. Two-tailed paired-samples t test, linear regression, independent t test, and 1-way analysis of variance were used for data analysis.

RESULTS: The 2-tailed paired-samples t test showed significant differences between the levels of nickel in the control and experimental groups (t [49] = 9.967; P <0.001). The linear regression test showed a significant relationship between mobile phone usage time and the nickel release (F [1, 48] = 60.263; P <0.001; R(2) = 0.577).

CONCLUSIONS: Mobile phone usage has a time-dependent influence on the concentration of nickel in the saliva of patients with orthodontic appliances.

http://1.usa.gov/1fa5FyQ

Highlights

• Radiofrequencies from mobile phones and nickel concentrations in saliva were examined.

• Mobile phone radiation is positively correlated with nickel concentration in saliva.

• Nickel concentrations in saliva were different in men and women.

Excerpts

An integral part of modern telecommunication is the mobile phone, which may have negative effects on different organs and cells. These negative impacts culminate from radiofrequency electromagnetic radiation (RFER) emitted from mobile phones. From 1990 to 2011, worldwide mobile phone subscriptions grew from 12.4 million to over 5.6 billion, and the global pandemic usage of mobile phones was about 70% as of 2011. Insufficient understanding of the potential adverse health effects of mobile phones have raised concerns among health care professionals.

According to the proximity of mobile phones to the oral cavity during the conversation period and the metallic orthodontic appliances in the mouth, there might be a serious risk in exposure of these appliances to the mobile phone radiation. Archwires, headgear, bands, and brackets used in orthodontics mainly consist of nickel. The harmful effects of nickel have been systematically investigated at the levels of the cells, tissues, organs, and organisms. According to the International Agency for Research on Cancer, nickel compounds are classified as carcinogenic to humans, but it is still unclear which forms of nickel pose the greatest risk. Nickel complexes in the form of arsenides and sulphides are carcinogenic, allergenic, and mutating substances even at nontoxic concentrations. Nickel might induce DNA alterations mainly through basic damage and DNA-strand scission in G12 cultured cells. Empirically, a biologic limit of 30 μg per gram has been proposed for nickel in the urine of workers exposed to soluble nickel compounds at the end of their shifts.

Nickel is a common metal that can cause allergic contact dermatitis more than all other metals. Previous studies have indicated that approximately 10% of the population is sensitive to nickel, and this sensitivity is more commonly seen in female patients.

The anatomic location of the parotid gland (at the anterior border of the external ear and between the mandibular ramus and the sternocleidomastoid muscle, 4- to 10-mm deep under the skin surface) makes it a conceivable candidate to be influenced by exposure to RFER on the side of the head where the mobile phone is held. Some researchers, in both human and animal studies, have confirmed that mobile phones cause significant increases in salivary oxidative stress, salivary flow, total proteins, and albumin, whereas amylase activity was decreased. In a nationwide case-control study, Sadetzki et al examined the correlation between parotid gland tumors and mobile phone usage and indicated a positive dose-dependent response trend. Thus, the RFER emitted from mobile phones may influence the amount of nickel released from the fixed orthodontic appliances.

… the aim of this study was to test the hypothesis that exposure to RFER emitted by mobile phones can affect the level of nickel in saliva. In addition, the effect of different times of exposure to the RFER was evaluated on the concentration of nickel in saliva.

Fifty healthy patients (25 men, 25 women; average age, 25.2 years; range, 23-26 years) who had fixed orthodontic appliances were selected for the study. Candidates needed placement of full orthodontic appliances for at least 2 months and no more than 4 months to satisfy the inclusion criterion.

During the regular checkups, the patients were asked not to use their cell phones for 1 week, and saliva samples were taken from them at the end of the week (this was considered the control group). For the next visit, a chronometer was given to the patients to calculate how many minutes they used their cell phone during the second week of the experiment. At the end of the second week, saliva samples were again collected, and the sexes, ages, and cell phone usage times were also recorded; this was considered the experimental group. The saliva samples were sent to the laboratory for further analysis.

The main outcome of the study was a significantly higher concentration of nickel ions in patients' saliva after using their mobile phones compared with the control group. The mobile phones used in this study had emissions of radiation in the normal range of 800 to 2200 MHz, as mentioned above.

The concentrations of salivary calcium, magnesium, and phosphate were lower in the mobile user group. Our results showed that the concentrations of nickel ions after using a cell phone for 1 week were significantly higher than the concentrations in the control group. This might be attributed to the greater flow rate and the lower concentration of the components in saliva, which in turn result in more nickel released from fixed orthodontic appliances into the saliva.

The linear regression test showed a positive significant increase in nickel concentration with mobile phone usage time. In other words, the longer the exposure to the RFEF emitted by a mobile phone, the greater the concentration of nickel in saliva.

According to results of our study, mobile phone radiation might cause DNA damage indirectly by influencing the release of nickel from fixed orthodontic appliances. Thus, the necessity of studying the effects of this radiation on metal ions released from fixed orthodontic appliances in adjacent tissues seems to be undeniable.

Conclusions

According to the outcomes of this study, it can be concluded that mobile phone radiation, regardless of the type of phone, can influence the concentration of nickel in saliva in a time-dependent manner. In addition, this adverse effect of radiation on the release of nickel was more prominent in women because of longer usage times. Future large-scale studies, which should include more parameters such as the effects on the parotid glands or the saliva flow rate, are needed.

Sunday, March 4, 2018

Acoustic Neuroma and Cell Phone Use

Studies that report evidence of increased risk of acoustic neuroma associated with

long-term cell phone use

Acoustic neuroma, also known as vestibular schwannoma, like heart schwannoma arises from the Schwann cells, but unlike its counterpart in the heart, it is usually a slow-growing tumor and not cancerous.

Acoustic neuroma develops on the main nerve leading from the inner ear to your brain. This nerve influences balance and hearing, and pressure from an acoustic neuroma can cause hearing loss, ringing in your ear and unsteadiness. Occasionally, it can interfere with brain functioning.

Two experimental studies have found evidence of increased incidence of heart schwannoma in male rats from exposure to cell phone radiation: National Toxicology Program (NTP) Finds Cell Phone Radiation Causes Cancer.

Nine peer-reviewed studies, including one cohort study, have found evidence that long-term cell phone use is associated with increased risk of acoustic neuroma in humans (see below).

April 26, 2017

Cohort Studies

Benson et al, 2013 (acoustic neuroma) - UK Million Women cohort study

For acoustic neuroma, there was an increase in risk with long term use vs never use (10+ years: RR = 2.46, 95% CI = 1.07-5.64, P = 0.03), the risk increasing with duration of use (trend among users, P = 0.03).

https://www.ncbi.nlm.nih.gov/pubmed/23657200

Case-Control Studies

Moon et al, 2014

Vestibular schwannomas (VSs) grow in the region where the energy from mobile phone use is absorbed. We examined the associations of VSs with mobile phone use. This study included 119 patients who had undergone surgical tumor removal. We used two approaches in this investigation. First, a case-control study for the association of mobile phone use and incidence of VSs was conducted. Both cases and controls were investigated with questions based on INTERPHONE guidelines. Amount of mobile phone use according to duration, daily amount, and cumulative hours were compared between two groups. We also conducted a case-case study. The location and volume of the tumors were investigated by MRI. Associations between the estimated amount of mobile phone use and tumor volume and between the laterality of phone use and tumor location were analyzed. In a case-control study, the odds ratio (OR) of tumor incidence according to mobile phone use was 0.956. In the case-case study, tumor volume and estimated cumulative hours showed a strong correlation (r(2) = 0.144, p = 0.002), and regular mobile phone users showed tumors of a markedly larger volume than those of non-regular users (p < 0.001). When the analysis was limited to regular users who had serviceable hearing, laterality showed a strong correlation with tumor side (OR = 4.5). We found that tumors may coincide with the more frequently used ear of mobile phones and tumor volume that showed strong correlation with amount of mobile phone use, thus there is a possibility that mobile phone use may affect tumor growth.

https://www.ncbi.nlm.nih.gov/pubmed/23975478

Hardell et al, 2013 (acoustic neuroma)

We previously conducted a case-control study of acoustic neuroma. Subjects of both genders aged 20-80 years, diagnosed during 1997-2003 in parts of Sweden, were included, and the results were published. We have since made a further study for the time period 2007-2009 including both men and women aged 18-75 years selected from throughout the country. These new results for acoustic neuroma have not been published to date. Similar methods were used for both study periods. In each, one population-based control, matched on gender and age (within five years), was identified from the Swedish Population Registry. Exposures were assessed by a self-administered questionnaire supplemented by a phone interview. Since the number of acoustic neuroma cases in the new study was low we now present pooled results from both study periods based on 316 participating cases and 3,530 controls. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index (SEI). Use of mobile phones of the analogue type gave odds ratio (OR) = 2.9, 95% confidence interval (CI) = 2.0-4.3, increasing with >20 years latency (time since first exposure) to OR = 7.7, 95% CI = 2.8-21. Digital 2G mobile phone use gave OR = 1.5, 95% CI = 1.1-2.1, increasing with latency >15 years to an OR = 1.8, 95% CI = 0.8-4.2. The results for cordless phone use were OR = 1.5, 95% CI = 1.1-2.1, and, for latency of >20 years, OR = 6.5, 95% CI = 1.7-26. Digital type wireless phones (2G and 3G mobile phones and cordless phones) gave OR = 1.5, 95% CI = 1.1-2.0 increasing to OR = 8.1, 95% CI = 2.0-32 with latency >20 years. For total wireless phone use, the highest risk was calculated for the longest latency time >20 years: OR = 4.4, 95% CI = 2.2-9.0. Several of the calculations in the long latency category were based on low numbers of exposed cases. Ipsilateral use resulted in a higher risk than contralateral for both mobile and cordless phones. OR increased per 100 h cumulative use and per year of latency for mobile phones and cordless phones, though the increase was not statistically significant for cordless phones. The percentage tumour volume increased per year of latency and per 100 h of cumulative use, statistically significant for analogue phones. This study confirmed previous results demonstrating an association between mobile and cordless phone use and acoustic neuroma.

https://www.ncbi.nlm.nih.gov/pubmed/23877578

Hardell et al, 2013

Regarding acoustic neuroma ipsilateral mobile phone use in the latency group ≥10 years gave OR=1.81, 95% CI=0.73-4.45. For ipsilateral cumulative use ≥1640h OR=2.55, 95% CI=1.50-4.40 was obtained. Also use of cordless phones increased the risk for glioma and acoustic neuroma in the Hardell group studies.

https://www.ncbi.nlm.nih.gov/pubmed/23261330

Interphone Study Group, 2011

The odds ratio (OR) of acoustic neuroma with ever having been a regular mobile phone user was 0.85 (95% confidence interval 0.69-1.04). The OR for ≥10 years after first regular mobile phone use was 0.76 (0.52-1.11). There was no trend of increasing ORs with increasing cumulative call time or cumulative number of calls, with the lowest OR (0.48 (0.30-0.78)) observed in the 9th decile of cumulative call time. In the 10th decile (≥1640 h) of cumulative call time, the OR was 1.32 (0.88-1.97); there were, however, implausible values of reported use in those with ≥1640 h of accumulated mobile phone use. With censoring at 5 years before the reference date the OR for ≥10 years after first regular mobile phone use was 0.83 (0.58-1.19) and for ≥1640 h of cumulative call time it was 2.79 (1.51-5.16), but again with no trend in the lower nine deciles and with the lowest OR in the 9th decile. In general, ORs were not greater in subjects who reported usual phone use on the same side of the head as their tumour than in those who reported it on the opposite side, but it was greater in those in the 10th decile of cumulative hours of use.

https://www.ncbi.nlm.nih.gov/pubmed/21862434

Hardell et al, 2009

For acoustic neuroma, the highest OR was found for ipsilateral use and >10 year latency, for mobile phone OR=3.0, 95% CI=1.4-6.2 and cordless phone OR=2.3, 95% CI=0.6-8.8.

https://www.ncbi.nlm.nih.gov/pubmed/19513546

Hardell et al, 2006

Regarding acoustic neuroma analogue cellular phones yielded odds ratio (OR) = 2.9, 95 % confidence interval (CI) = 2.0-4.3, digital cellular phones OR = 1.5, 95 % CI = 1.1-2.1 and cordless phones OR = 1.5, 95 % CI = 1.04-2.0.

https://www.ncbi.nlm.nih.gov/pubmed/17034627

Schoemaker et al, 2005

Risk of a tumour on the same side of the head as reported phone use was raised for use for 10 years or longer (OR = 1.8, 95% CI: 1.1-3.1). The study suggests that there is no substantial risk of acoustic neuroma in the first decade after starting mobile phone use. However, an increase in risk after longer term use or after a longer lag period could not be ruled out.

https://www.ncbi.nlm.nih.gov/pubmed/16136046

Lonn et al, 2004

The overall odds ratio for acoustic neuroma associated with regular mobile phone use was 1.0 (95% confidence interval = 0.6-1.5). Ten years after the start of mobile phone use the estimates relative risk increased to 1.9 (0.9-4.1); when restricting to tumors on the same side of the head as the phone was normally used, the relative risk was 3.9 (1.6-9.5).

https://www.ncbi.nlm.nih.gov/pubmed/15475713