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Aiming at the engineering problem that 5G base station antenna is difficult to locate efficiently in complex electromagnetic environment, a two-stage positioning method of 5G base station antenna substation is proposed, which considers signal path loss and antenna RF radiation. Firstly, the path loss solution model of the 5G base station antenna signal in the substation is established, and the RF radiation solution model generated by the coupling excitation of 5G high-frequency electromagnetic wave and the metal shell of the electrical equipment is constructed based on the big element physical optics method. Secondly, combining the advantages of particle swarm optimization (PSO) and interior point algorithm, the antenna positioning method considering path loss and RF radiation is constructed. Among them, in the first stage, the minimum loss of 5G signal path in the substation is taken as the goal, and the antenna stations in the substation are searched globally to get the optimal pre-selected position. In the second stage, the antenna position is calibrated according to the pre-selected position, so that the interference of RF radiation is minimized, and the final position is output. Finally, a 500 kV 5G substation in Henan Province was taken as the simulation object. Compared with the original scheme, the simulation results ensured the minimum 5G path loss in the substation and took into account the electromagnetic compatibility of the equipment in the substation. The effectiveness of the location strategy for maintaining the safe operation of the substation is verified, and it can provide a reference for the 5G base station antenna positioning project of the substation. Article highlights: Considering the influence of 5G high-frequency electromagnetic wave on the electrical equipment in the substation, the positioning accuracy of 5G base station antenna in the substation is improved. The large area physical optics method can improve the calculation time and accuracy of radiofrequency radiation field intensity Combining the advantages of particle swarm optimization and interior point method, it can effectively avoid the problem of local optimal solution of location selection The simulation results show that the proposed method not only improves the location accuracy of 5G base station antennas in substations, but also applies to 5G base station antennas in more complex engineering environments [ABSTRACT FROM AUTHOR]

Abstract Aiming at the engineering problem that 5G base station antenna is difficult to locate efficiently in complex electromagnetic environment, a two-stage positioning method of 5G base station antenna substation is proposed, which considers signal path loss and antenna RF radiation. Firstly, the path loss solution model of the 5G base station antenna signal in the substation is established, and the RF radiation solution model generated by the coupling excitation of 5G high-frequency electromagnetic wave and the metal shell of the electrical equipment is constructed based on the big element physical optics method. Secondly, combining the advantages of particle swarm optimization (PSO) and interior point algorithm, the antenna positioning method considering path loss and RF radiation is constructed. Among them, in the first stage, the minimum loss of 5G signal path in the substation is taken as the goal, and the antenna stations in the substation are searched globally to get the optimal pre-selected position. In the second stage, the antenna position is calibrated according to the pre-selected position, so that the interference of RF radiation is minimized, and the final position is output. Finally, a 500 kV 5G substation in Henan Province was taken as the simulation object. Compared with the original scheme, the simulation results ensured the minimum 5G path loss in the substation and took into account the electromagnetic compatibility of the equipment in the substation. The effectiveness of the location strategy for maintaining the safe operation of the substation is verified, and it can provide a reference for the 5G base station antenna positioning project of the substation.

With the widespread use of mobile phones, laptops, and WIFI, the effects of radio frequency radiation (RFR) on human health are of increasing concern, and there are particular concerns about its reproductive toxicity. Studies have shown that the reproductive system is a sensitive target for RFR. In males, RFR is associated with decreased sperm quality and serum testosterone levels, but there are few studies on the biological effects of RFR by altering physical parameters on the male reproductive system. This paper introduced common sources of RFR, reviewed the toxic effects and mechanisms of RFR targeting male reproductive system from the aspects of spermatogenic cells, sperm structure, blood-testicular barrier, and testicular function, and analyzed male reproductive system related toxic effects of RFR by varying physical parameters including frequency, treatment duration, and specific absorption rate, so as to provide a theoretical basis and scientific basis for the safe and reasonable use of radio frequency electromagnetic field by humans and subsequent in-depth research.

The time dynamics of luminescence intensity in the spectral maximum from the Nafion polymer membrane surface is studied. Luminescence was excited by a continuous wave diode laser with wavelength λ = 369 nm. The polymer membrane swelled in deionized water with a deuterium content of 157 ppm, as well as in deuterium-depleted water (deuterium content of 3 ppm). In photoluminescence spectroscopy experiments, a polymer Nafion membrane is irradiated with a radiofrequency electromagnetic wave at a frequency of 3 MHz. Submicrometer particles of colloidal gold are added to liquid samples. It turns out that when such particles added to deionized water and irradiated with radio frequency waves cause stochastic jumps in the luminescence intensity. This effect is absent as submicrometer gold particles are added to deuterium-depleted water. A qualitative model is proposed that relates luminescence intensity jumps to the effects of radio frequency radiation absorption on metal submicrometer particles and the emergence of a convection countercurrent near the membrane due to Rayleigh instability. [ABSTRACT FROM AUTHOR]

In this paper, radio-frequency radiation levels from some selected Base Transceiver Stations of different network providers (MTN, 9mobile, Airtel and Globacom) within Kaduna metropolis, Kaduna State, Nigeria were measured using a portable hand-held spectrum analyzer model 2658A, within radial distance intervals of 20 m to 100 m from the foot of each Base Transceiver Station. The measured values range between 0.24 μWm^-2 to 30.42 μWm^-2 with an average value of between 0.298 μWm^-2 to 14.578 μWm^-2 respectively. The measured radiation levels were found to be less than the acceptable standard value of 4.5 Wm^-2 recommended by International Commission on Non-ionizing Radiation Protection for Global System for Mobile communication with frequency 900 MHz. Results obtained show exposure to RF emissions from the sampled Base Transceiver Stations will not impose health risk to humans living within that area.

This paper is aimed at estimating Radio Frequency (RF) radiation absorbed by humans around Base Transceiver Stations (BTS) within Kaduna metropolis. RF radiation absorbed by humans from forty two (42) selected (BTS) tagged M1 to M42 of the four major network providers (MTN, 9mobile, Airtel and Globacom) within Kaduna metropolis, Kaduna State, Nigeria within radial distance intervals of 20 m to 100 m from the foot of each BTS were estimated. The Average Power Density (PDAve) and Specific Absorption Rate of data obtained from these BTS were computed, and the results indicated that the average amount of SAR for the selected forty two (42) base transceiver BTS facilities were within the range of 16.9 - 331.7 × 10-9 W/kg and 0.648-10.659 × 10-6 W/m² respectively. These values are lower than the recommended limit by International Commission on Non Ionization Radiation Protection (ICNIRP) which is 0.08 W/kg for the human body. This study has shown that RF radiation absorbed by people either residing or transiting the study area has negligible effect on their health. [ABSTRACT FROM AUTHOR]

Radiofrequency radiation (RFR) is a type of non-ionizing electromagnetic radiation that includes radiowaves and microwaves with a frequency range between 3 KHz and 300 GHz. Mobile phones operate with RFR and are used tremendously resulting in increased and continuous exposure of humans to these radiations. On the other hand, nanoparticles are also being used extensively in various fields. The increasing use of radiofrequency radiations and nanoparticles has become a concern to the general public. Not many studies have reported the cumulative effect of these stressors. Hence, the present investigation was aimed to find out their cumulative effect on the mammalian system. In this study manganese nanoparticles (MNPs) were synthesized and characterized. Adult male Wistar rats were exposed to MNPs and mobile phone radiation for 45 days and their separate, as well as cumulative impact, was investigated. The effect of the MNPs and RFR on liver, kidney, and reproductive parameters were studied. Histopathology as well as liver and kidney parameters were altered when exposed to MNPs and RFR separately. However, their combined treatment did not show a synergistic toxic response in liver and kidney functions which may be due to the fact that the radiation level is low, specific absorption rate (SAR) is subthermal (0.04 W/kg) and liver and kidney are located intra abdominally, hence they would absorb comparatively lesser radiation than the testicles. MNPs and RFR both caused a highly significant decrease in sperm count, which further decreased in the combined treatment (MNPs + RFR). These results indicate that the combined treatment of these stressors can have an additive toxic response to the male reproductive system. [ABSTRACT FROM AUTHOR]

The use of electronic devices such as mobile phones has had a long stretch of rapid growth all over the world. Therefore, exposure to radio frequency radiation (RFR) has increased enormously. Here, we aimed to assess the balance between cell death and proliferation and also investigate the involvement of the JNK/p38 MAPK signaling pathway in the testis of rats exposed to 900 MHz RFR in acute and chronic periods (2 h/day, 5 days/week) for 1 or 10 weeks, respectively. The expression of proliferating cell nuclear antigen (PCNA), Bcl-xL, cleaved caspase-3, phosphorylated-JNK (p-JNK), and phosphorylated-p38 (p-p38) was analyzed in line with histopathology and TUNEL analysis in rat testis. There were no histopathological differences between sham and RFR groups in the acute and chronic groups. PCNA expression was not altered between groups in both periods. However, alterations for cleaved caspase-3 and Bcl-xL were observed depending on the exposure period. TUNEL analysis showed a significant increase in the RFR group in the acute period, whereas no difference in the chronic groups for the apoptotic index was reported. In addition, both p-p38 and p-JNK protein expressions increased significantly in RFR groups in both periods. Our study indicated that 900 MHz RFR might result in alterations during acute period exposure for several parameters, but this can be ameliorated in the chronic period in rat testis. Here, we also report the involvement of the p38/JNK-mediated MAPK pathway after exposure to 900 MHz RFR. Hence, this information might shed light in future studies toward detailed molecular mechanisms in male reproduction and infertility. [ABSTRACT FROM AUTHOR]

Objective: Some studies have claimed that long-term conversation with mobile phones can cause hearing loss. However, it has not been investigated whether exposure to mobile phones during pregnancy affects the hearing of babies in the womb. Therefore, the aim of this human study was to investigate the effects of intrauterine radiofrequency radiation (RFR) exposure emitted from mobile phones on the hearing of newborns. Methods: The study population comprised 149 newborns. Pregnant women in this study were divided into 4 groups according to RFR exposure duration, such as non-exposure to RFR, exposure to RFR for 2-15 min/day, exposure to RFR for 15-6Q min/day, and exposure to RFR for more than 60 min/day. The results of the hearing screening analyses of the newborns, which were performed using transiently evoked otoacoustic emission and auto auditory brainstem response, were investigated retrospectively. Results: The results of this study indicated that 900 and 1800 MHz RFR exposure during pregnancy did not cause hearing loss in newborns. Conclusion: In conclusion, we observed that the hearing sensitivity and peripheral sound perception of newborns were not affected by RFR exposure emitted from mobile phones during the intrauterine period. Further studies should be performed to illuminate the subject. [ABSTRACT FROM AUTHOR]

Background: The study of Heart rate is very important the body heart is directly related to heart rate, the autonomic cardiovascular examination provides necessary information about function of the autonomic nervous system as well functional capacities of effectors heart and vessels and other associated part with radiation. Objective: To study the effect of jammer on autonomic nervous system as measured by heart rate. Patients and Methods: Heart rates of 10 males (age 21-51 years), and 10 females (age 20-54 years) were measured and recorded before, during using jammer for 15 minutes, 30 minutes, and 45 minutes, and one hour after shutting down the device . Results: The results clearly indicate that jammer radiation induced high fluctuations in heart rate variability of recovery period (after15 minutes using jammer) and show that the change of heart rate variability signal during jammer exposure is not permanent. There was no statistically significant difference observed in heart rate. Conclusion: The heart rate flection resulting from exposure to radiofrequencies of jammer are depending on the orientation of both electric &magnetic field of the electromagnetic radiation, the greater increase in heart rate that occurred during E orientation irradiation. [ABSTRACT FROM AUTHOR]

The impact of cellular phone radiation on human health is the subject of current mindfulness and is an outcome of the huge increase in phone usage throughout the world. Phones use electromagnetic radiation in the microwave range. The issue is associated with wireless use for 50 minutes and above. The excessive use of mobile phone may cause brain tumors. Nowadays the most commonly developed brain tumor type is GBM (Glioblastoma) in multiform and Malignant Astrocytoma. In this paper, we focus on the causes of brain tumor (cancer) due to the cell phone as this increase in glucose metabolism. The aim of the study is to address the aforementioned problems associated with the cell phone. MATLAB programming to detect a brain tumor has been used. We have conducted MRI (Magnetic Resonance Imaging) study to get the best images and results.

Radio frequency (RF) electromagnetic radiation over range of 30 ∼ 800 MHz from laser induced breakdown of air are investigated. The RF radiation, under different laser energies, laser polarization directions and detect position are measured. It is found that a much stronger RF signals emitted from air plasma was observed at moderate laser pulse energy in our case. The measured RF signal of air plasma is found to depend on laser polarization direction and pulse energy, and the spatial distribution of RF radiation is anisotropy. Underlying physics responsible for laser parameter-dependent RF emission, rich in emission lines and anisotropy of spatial distribution of RF emission of the laser induced air plasma are discussed. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate prenatal exposure to radiofrequency radiation (RFR) from telecommunication using a mobile phone questionnaire, operator data logs of mobile phone use and a personal exposure meter (PEM). Material and Methods: The study included 1228 mother–infants pairs from the Mothers and Children’s Environmental Health (MOCEH) study – a multicenter prospective cohort study ongoing since 2006, in which participants were enrolled at ≤ 20 weeks of pregnancy, with a follow-up of a child birth and growth to assess the association between prenatal environmental exposure and children’s health. The questionnaire included the average calling frequency per day and the average calling time per day. An EME Spy 100 PEM was used to measure RFR among 269 pregnant women from November 2007 to August 2010. The operators’ log data were obtained from 21 participants. The Spearman’s correlation test was performed to evaluate correlation coefficient and 95% confidence intervals between the mobile phone use information from the questionnaire, operators’ log data, and data recorded by the PEM. Results: The operators’ log data and information from the self-reported questionnaire showed significantly high correlations in the average calling frequency per day (ρ = 0.6, p = 0.004) and average calling time per day (ρ = 0.5, p = 0.02). The correlation between information on the mobile phone use in the self-reported questionnaire and exposure index recorded by the PEM was poor. But correlation between the information of the operators’ log data and exposure index for transmission of mobile communication was significantly high: correlation coefficient (p-value) was 0.44 (0.07) for calling frequency per day, and it was 0.49 (0.04) for calling time per day. Conclusions: The questionnaire information on the mobile phone use showed moderate to high quality. Using multiple methods for exposure assessment might be better than using only one method. Int J Occup Med Environ Health 2016;29(6):959–972

The level of radio frequency (RF) electromagnetic field emitted from a military armoured vehicle antenna was investigated to identify possible adverse health effect on personnel, especially in the near field region. Both E-Field and H-Field radiations levels emitted from antenna were recorded by emphasising on the main areas of crew working station. To date, open literature on military vehicle and equipment RF radiation hazard safety assessment has limited numbers of discussion especially on RF source distance, location and mode of power transmission. In this investigation, RF levels from two radio antennas were measured, high frequency (HF) and very high frequency (VHF) with the low and high-power transmission. Measurements were taken in two distinct locations namely; commander and gunner respectively with three different conditions; open hatch, close hatch and open hatch with standing crews which representing the normal and combat situations. The measured E-Field and H-Field levels were then assessed for compliance with occupational reference levels of Military Standard 464C, The Institute of Electrical and Electronics Engineers (IEEE) for Military Workplace standards and International Commission on Non-Ionising Radiation Protection (ICNIRP) guidelines. The occupational standard was exceeded on commander and gunner area at certain condition; nevertheless, the rest of the conditions complied within the occupational standard. [ABSTRACT FROM AUTHOR]

As the body centric communication technology develops in monitoring real-time healthcare, fitness, sports, and military, significant attention arises in regarding possible health risks. The aim of this study is to evaluate radio frequency exposure level of various types of wearable devices in terms of the available international recommendations. Specific absorption rate and maximum temperature increase are studied in the human ear and mouth when they are exposed to handheld transmitters. The human brain and the mouth are modeled using the simulation program and the handheld transmitters are realized with microstrip patch antenna. The simulations depict that the dosimetry for handheld transmitters operated next to the body is below the standards. [ABSTRACT FROM AUTHOR]

Background and aim We reexamine whether radio frequency radiation (RFR) in the occupational and military settings is a human carcinogen. Methods We extended an analysis of an already-reported case series of patients with cancer previously exposed to whole-body prolonged RFR, mainly from communication equipment and radar. We focused on hematolymphatic (HL) cancers. We used analysis by percentage frequency (PF) of a cancer type, which is the proportion of a specific cancer type relative to the total number of cancer cases. We also examined and analyzed the published data on three other cohort studies from similar military settings from different countries. Results The PF of HL cancers in the case series was very high, at 40% with only 23% expected for the series age and gender profile, confidence interval CI95%: 26–56%, p<0.01, 19 out of 47 patients had HL cancers. We also found high PF for multiple primaries. As for the three other cohort studies: In the Polish military sector, the PF of HL cancers was 36% in the exposed population as compared to 12% in the unexposed population, p<0.001. In a small group of employees exposed to RFR in Israeli defense industry, the PF of HL cancers was 60% versus 17% expected for the group age and gender profile, p<0.05. In Belgian radar battalions the HL PF was 8.3% versus 1.4% in the control battalions as shown in a causes of deaths study and HL cancer mortality rate ratio was 7.2 and statistically significant. Similar findings were reported on radio amateurs and Korean war technicians. Elevated risk ratios were previously reported in most of the above studies. Conclusions The consistent association of RFR and highly elevated HL cancer risk in the four groups spread over three countries, operating different RFR equipment types and analyzed by different research protocols, suggests a cause-effect relationship between RFR and HL cancers in military/occupational settings. While complete measurements of RFR exposures were not available and rough exposure assessments from patients interviews and from partial exposure data were used instead, we have demonstrated increased HL cancers in occupational groups with relatively high RFR exposures. Our findings, combined with other studies, indicate that exposures incurred in the military settings evaluated here significantly increased the risk of HL cancers. Accordingly, the RFR military exposures in these occupations should be substantially reduced and further efforts should be undertaken to monitor and measure those exposures and to follow cohorts exposed to RFR for cancers and other health effects. Overall, the epidemiological studies on excess risk for HL and other cancers together with brain tumors in cellphone users and experimental studies on RFR and carcinogenicity make a coherent case for a cause-effect relationship and classifying RFR exposure as a human carcinogen (IARC group 1). [ABSTRACT FROM AUTHOR]

This work describes the implementation of an RF based wireless charging system using RF transmitting and receiving modules. The objective of this work is to implement a system that has the ability to interact and communicate wirelessly within short range. This mobile wireless charging switching system consists of two sections, the transmitting and the receiving section. Each section was interfaced to 433MHz transmitting and receiving modules. The transmitter section of the wireless mobile charging system sends bursts of 433MHz signal through push button switch which is used in the initiation of the charging process to the receiver; when this signal is received by the receiver, it activates a relay which in turn switches on the internal power that comprises the backup battery, DC-to DC converter via a Universal Serial Bus (USB) port to the mobile device to begin charging. This work was able to achieve a wireless transfer of power for distance of about one metre between the transmitter and the receiver. [ABSTRACT FROM AUTHOR]

The impact of cellular phone radiation on human health is the subject of current mindfulness and is an outcome of the huge increase in phone usage throughout the world. Phones use electromagnetic radiation in the microwave range. The issue is associated with wireless use for 50 minutes and above. The excessive use of mobile phone may cause brain tumors. Nowadays the most commonly developed brain tumor type is GBM (Glioblastoma) in multiform and Malignant Astrocytoma. In this paper, we focus on the causes of brain tumor (cancer) due to the cell phone as this increase in glucose metabolism. The aim of the study is to address the aforementioned problems associated with the cell phone. MATLAB programming to detect a brain tumor has been used. We have conducted MRI (Magnetic Resonance Imaging) study to get the best images and results. [ABSTRACT FROM AUTHOR]

Present study was under taken to predict the possible DNA damages (genotoxicity) and carcinogenicity caused by radiofrequency radiations (RF) to living tissue. Dry seeds of chickpea were treated with GSM cell phone (900 MHz) and laptop (3.31 GHz) as RF source for 24 and 48 h. Untreated seeds were used as (0 h) negative control and Gamma rays (250 Gray) as positive control. Plant chromosomal aberration assay was used as genotoxicity marker. All the treatment of RF inhibits seed germination percentage. 48 h laptop treatment has the most negative effect as compared to untreated control. A decrease was observed in mitotic index (M.I) and increase in abnormality index (A.I) with the increase in exposure duration and frequency in (Hz). Cell membrane damages were also observed only in 48 h exposure of cell phone and laptop (RF). Maximum nuclear membrane damages and ghost cells were again recorded in 48 h exposure of cell phone and laptop. The radiofrequency radiations (900 MHz and 3.31 GHz) are only genotoxic as they induce micronuclei, bi-nuclei, multi-nuclei and scattered nuclei but could be carcinogenic as 48 h incubation of RF induced fragmentation and ghost cells. Therefore cell phones and laptop should not be used unnecessarily to avoid possible genotoxic and carcinogenic effects. [ABSTRACT FROM AUTHOR]

Novel ion traps that provide either a static or a dynamic magnetic gradient field allow for the use of radio-frequency radiation for coupling internal and motional states of ions, which is essential for conditional quantum logic. We show that the Hamiltonian describing this coupling in the presence of a resonant dynamic gradient, is identical, in a dressed state basis, to the Hamiltonian in the case of a static gradient. The coupling strength is in both cases described by the same effective Lamb-Dicke parameter. This insight can be used to overcome demanding experimental requirements when using a dynamic gradient field for state-of-the-art experiments with trapped ions, for example, in quantum information science. At the same time, this insight opens new experimental perspectives by way of using a single resonant or detuned dynamic gradient field, inducing long-range coupling, for conditional multi-qubit dynamics.

The biochemical status in the saliva of 12 males before/after using mobile phone has been evaluated. Radio frequency signals of 1800 MHz (continuous wave transmission, 217 Hz modulate and Global System for Mobile Communications [GSM - non-DTX]) with 1.09 w/kg specific absorption rate (SAR) value were used for 15 and 30 min. Cell phone radiation induced a significant increase of superoxide dismutase (SOD); there was a statistically significant effect of talking time on the levels of SOD, F(2, 33) = 8.084, p < 0.05, ω = 0.53. The trend analysis suggests a significant quadratic trend, F(1, 33) = 4.891, p < 0.05; indicating that after 15 min of talking the levels of SOD increased, but as talking time increased the SOD activity started to drop. In contrast to this, there was no statistically significant effect of talking time on the level of salivary albumin, cytochrome c, catalase or uric acid. Results suggest that exposure to electromagnetic radiation may exert an oxidative stress on human cells as evidenced by the increase in the concentration of the superoxide radical anion released in the saliva of cell phone users. [ABSTRACT FROM AUTHOR]

In this study, we aimed to investigate the effects of 1800 and 2100 MHz Radio Frequency (RF) radiation on the number of micronucleus (MN) in exfoliated bladder cells of rat which shows the genotoxic damage. Exposure period was 30 min/day, 6 days/week for a month and two months exposure periods. Thirty male wistar albino rats were used for five groups: Group I ( n = 6): 1800 MHz RF exposed animals for one month, Group II ( n = 6): 2100 MHz RF exposed animals for one month, Group III ( n = 6): 2100 MHz RF exposed for two months, Group IV ( n = 6): control group for one month, Group V ( n = 6): control group for two months. Rats of the control groups were housed in their home cages during the entire experimental period without subjecting to any experimental manipulation. 1800 and 2100 MHz RF exposures did not result in any significant MN frequencies in rat bladder cells with respect to the control groups ( p > 0.05). There was no statistically significant difference between 2100 MHz RF exposed groups, either. Further studies are needed to demonstrate if there is any genotoxic effect, micronucleus formation in other tissues of rats. [ABSTRACT FROM AUTHOR]

This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3, or 4 h, at a specific absorption rate of 2 W/kg) to enhanced data rates for global system for mobile communication evolution-modulated radiofrequency radiation (RFR) at 900- and 1,800-MHz frequencies on the viability of the Hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt WST-1 by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4′,6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, TUNEL assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour exposure produced more pronounced effects than the other exposure durations. 1,800-MHz RFR had a larger impact on cell viability and Hep G2 injury than the RFR at 900 MHz. Morphological observations also supported the biochemical results indicating that most of the cells showed irregular nuclei pattern determined by using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 h of exposure to 1,800-MHz RFR. Our results indicate that the applications of 900- and 1,800-MHz (2 W/kg) RFR cause to decrease in the proliferation of the Hep G2 cells after 4 h of exposure. Further studies will be conducted on other frequency bands of RFR and longer duration of exposure. [ABSTRACT FROM AUTHOR]