Thursday, August 13, 2015

Cellphone use may be harmful for people with dental braces

Cellphone use may be harmful for people with dental braces

Electromagnetic Radiation Safety, Aug 13, 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 abstract for this study and excerpts from the paper are available on my Electromagnetic Radiation Safety web site


Federal court hearing on Berkeley's cell phone "right to know ordinance

Next Thursday, August 20th, the U.S. District Court in San Francisco will hold a hearing on the CTIA's motion for a preliminary injunction to block implementation of the City of Berkeley's cell phone "right to know" ordinance. 

Harvard Law Professor Lawrence Lessig will represent the City. The National Resources Defense Council (NRDC) has filed a brief in support of the City's law. For more information about this landmark law and the industry's lawsuit against the City of Berkeley see my regular updates.

Joel M. Moskowitz, Ph.D., Director
Center for Family and Community Health
School of Public Health
University of California, Berkeley

Electromagnetic Radiation Safety

News Releases:
Twitter:                 @berkeleyprc

No comments:

Post a Comment