US FDA Consumer Update

How much evidence is there that hand-held mobile phones might be harmful?

Briefly, there is not enough evidence to know for sure, either way; however, research efforts are on-going. The existing scientific evidence is conflicting and many of the studies that have been done to date have suffered from flaws in their research methods. Animal experiments investigating the effects of RF exposures characteristic of mobile phones have yielded conflicting results. A few animal studies, however, have suggested that low levels of RF could accelerate the development of cancer in laboratory animals. In one study, mice genetically altered to be predisposed to developing one type of cancer developed more than twice as many such cancers when they were exposed to RF energy compared to controls. There is much uncertainty among scientists about whether results obtained from animal studies apply to the use of mobile phones. First, it is uncertain how to apply the results obtained in rats and mice to humans. Second, many of the studies that showed increased tumor development used animals that had already been treated with cancer-causing chemicals, and other studies exposed the animals to the RF virtually continuously—up to 22 hours per day.

For the past five years in the United States, the mobile phone industry has supported research into the safety of mobile phones. This research has resulted in two findings in particular that merit additional study:

1.In a hospital-based, case-control study, researchers looked for an association between mobile phone use and either glioma (a type of brain cancer) or acoustic neuroma (a benign tumor of the nerve sheath). No statistically significant association was found between mobile phone use and acoustic neuroma. There was also no association between mobile phone use and gliomas when all types of types of gliomas were considered together. It should be noted that the average length of mobile phone exposure in this study was less than three years.

2.When 20 types of glioma were considered separately, however, an association was found between mobile phone use and one rare type of glioma, neuroepithelliomatous tumors. It is possible with multiple comparisons of the same sample that this association occurred by chance. Moreover, the risk did not increase with how often the mobile phone was used, or the length of the calls. In fact, the risk actually decreased with cumulative hours of mobile phone use. Most cancer causing agents increase risk with increased exposure. An ongoing study of brain cancers by the National Cancer Institute is expected to bear on the accuracy and repeatability of these results.(1)

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i58sr specifications

The Nextel i58sr was a standout device in the realm of communication technology, primarily catering to business and professional users. Released as part of Nextel's ruggedized phone lineup, the i58sr was designed with durability and functionality in mind, making it a reliable choice for users in demanding environments.

One of the defining features of the i58sr was its sturdy design. The phone was built to withstand tough conditions, with a rugged exterior that offered resistance to shocks, vibrations, and water. This made it ideal for users who worked in construction, outdoor activities, or any field where accidents and rough handling were a possibility.

The i58sr boasted a compact and lightweight form factor, making it portable and easy to handle. Its ergonomic design included a comfortable grip, essential for prolonged use in the field. The device also featured a clear display that provided essential information at a glance, ensuring that users could easily navigate through applications and features even in bright sunlight.

A significant highlight of the Nextel i58sr was its push-to-talk capability, which allowed for instant communication with other Nextel users. This feature enabled users to connect with team members quickly, facilitating coordination and enhancing productivity, especially in high-paced work environments. The phone also supported traditional voice calls, ensuring versatility in communications.

Technologically, the i58sr utilized Nextel's iDEN network, combining radio communication and cellular service to deliver unique features like two-way radio capability. This hybrid technology enhanced the range of communication options available to users, allowing for seamless transitions between direct radio and phone calls.

In terms of battery life, the i58sr performed admirably, providing extended usage capabilities that were crucial for users often away from power sources. This reliability was further complemented by the device's long-standing reputation for functionality, which included features like programmable buttons for quick access to frequently used functions.

In summary, the Nextel i58sr was a significant player in the domain of rugged communication devices. Its combination of durability, push-to-talk capabilities, and a reliable power source made it a preferred choice for professionals in various industries. By blending traditional voice calls with advanced push-to-talk technology, it stood out as an essential tool for effective communication in challenging environments.
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