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1.
During the last two decades, wireless communications (cell phones, Internet, WiFi technology) became the fastest developing technology that spread around the world. It is close to 5 billion mobile phones registered in both developed and developing countries. In addition to the users of these technologies, the entire world population is exposed to exponentially increasing radiofrequency (RF) radiation from base stations and satellite antennas. In this special issue of The Environmentalist, three other papers one way or another addressed the problems related to the impact of RF radiation on the contemporary life. This paper is focused on the importance of paying special attention on potential effects of wireless technologies on children brain. This is even more important because cell phones may be seen in the hands of children as little as 3–4 years in age. There is no way to assess and predict the potential damages of children brain exposed to RF radiation. For that reason, precautionary principle must be applied in discussing the potential hazard of the use of cell phones in such young age.  相似文献   

2.
The amount of waste electrical and electronic equipment (WEEE) has been rapidly growing in recent years. Estimation close to reality of the future amounts of WEEE as a function of time is critical to effective their management. Wastes from mobile phones and computers are one of the several subgroups of WEEE. The objective of this study was to estimate past and future trends in the generation of obsolete computers and mobile phones in Iran. For this purpose a combination of two models were used. At the beginning, time-series multiple lifespan model was used to estimate outflows end-of-life obsolete equipment. Then, using the simplified logistic function model by Excel software, the values of obsolete computers and mobile phones in the future were estimated. The study found that the amount of E-waste generation in the country was 20 million wasted computers until 2016 and 39 million wasted mobile phones until 2014. Results of the time series model analysis showed a total amount of 2.8 million waste computers would be reused by 2016 and 4.2 million mobile phones would be reused by 2014. The results of the logistic equation indicate that by the year 2040 there will be 50 million units of obsolete computers. According to the same model 90 million mobile phones will be obsolete by 2035. Increase in the number of computers and mobile phones was fitted into the logistic model and the results showed that the saturation level of generation of obsolete computers and mobile phones are 24 and 21 years respectively following the base year 2016 and 2014.  相似文献   

3.
Objectives This paper aims to provide evidence of an inductive electromagnetic bioeffect on the human brain, which is independent from sound waves and produced by mobile phones, in proximal field, through correlating the EEG data obtained from electrodes placed on both normal and cochlear deaf individuals. Methods Two groups of subjects are placed under controlled electromagnetic conditions inside a Faraday chamber, 12 healthy and another 12 suffering from cochlear deafness). Each is sitting on a chair, fitted with additional support, and holding a cellular phone 2 cm away form the right auricular, in order to avoid a thermal effect as much as possible. All of them, relaxed and with their eyes closed, are EEG recorded in a basal state with their mobile phones off. Then, each of them is again recorded under the same conditions but with the mobile on and listening to the same conversation. In order to assess the observed EEG changes, a statistical analysis by means of the FFT (Fast Fourier Transform) was carried out. Results For both, healthy and cochlear deaf, assimilation or integration of the mobile phone signal by some electrodes is to be found. This is due to the increase of amplitudes for alpha and theta waves, whereas the signal is not integrated in other electrodes. By correlating the spectra of frequencies of corresponding EEG records for the same brain areas, we have not observed significative differences for both groups. Conclusions A possible electromagnetic direct inductive, non-thermal, bioeffect on the human brain is observed. This effect is produced by the use of mobile phones and it bears no relation to the sound waves.  相似文献   

4.
作为“城市矿产”的典型代表,废弃手机因其废弃数量大、稀贵金属品位高等特性而备受关注,但在推进废弃手机回收过程中存在诸多问题。本文以推动产业发展为立足点,梳理了影响废弃手机回收的两级制衡要素,通过构建GREY-DEMATEL模型,定量评估各要素对废弃手机回收的影响程度并确定优先等级。其中,完善废弃手机回收的管理制度及相应的经济扶持政策成为短期内应着力解决的核心问题,从长期发展来看,废弃手机的前端收集应成为产业关注的重点。基于此,本文立足于废弃手机回收的短期目标及长远发展,分别提出相应的管理策略,为再生资源产业的良性发展提供对策建议。  相似文献   

5.
This study is aimed to clarify whether effect of low-level microwave radiation on human brain differs at different modulation frequencies. Resting EEG recordings were done on different groups of healthy volunteers. The 450 MHz microwave radiation modulated at 40 and 70 Hz (15 subjects) and 217 and 1,000 Hz (19 subjects) frequencies was applied. The results of our previous study at 7, 14 and 21 Hz modulation were included into analysis. Ten cycles of the exposure (1 min off and 1 min on) at each fixed modulation frequencies were applied. The field power density at the scalp was always 0.16 mW/cm2. Our results showed that microwave exposure increased the EEG energy at EEG frequencies lower or close to the modulation frequency. No effect was detected at EEG frequencies higher than the modulation frequency. Statistically significant changes were caused by exposure in the EEG alpha and beta frequency bands; no significant effect was detected in the theta band. Our results suggest that telecommunication devices with complex spectrum of modulation frequencies like mobile phone can affect all human EEG frequency bands.  相似文献   

6.
随着手机用户的增加,每年会产生大量的废旧手机。废旧手机一方面对环境构成潜在危害,一方面又具有回收利用的价值。本文针对我国目前废旧手机回收利用的现状,提出手机回收利用的措施,以有效应对电子垃圾污染,并实现资源的循环利用。  相似文献   

7.
本文围绕以手机为主的电子类生活垃圾回收环节,基于EPR电子生活垃圾回收实验及目前电子类生活垃圾的回收激励政策和效果,运用典型相关分析方法确定激励政策及政策效果的主要影响变量,研究以手机为主的电子类生活垃圾回收的激励政策与政策效果之间的关系,强化电子类生活垃圾回收的政策措施,扩大政策效果,促进资源的回收及再利用。本文设定的回收激励政策包括政府对废旧手机回收率的最低要求、优惠力度以及获得高优惠的最低回收率要求,政策效果包括废旧手机实际回收率、销售市场营业额以及生产者补贴总额等方面。研究结果表明,电子类生活垃圾回收激励政策与政策效果之间存在着显著的相关关系,其中,获得高优惠的最低回收率对废旧手机实际回收率有显著抑制作用,废旧手机回收率的最低要求对销售市场营业额有显著抑制作用。本文在此基础上给出了政策建议。  相似文献   

8.
Summary The thermal effect due to electromagnetic absorption by human tissues is investigated at different frequencies ranging from 101–1016 Hz. Special emphasis is being considered in the microwave band used in wireless communications of the mobile industry. The present work examines basically the thermal effect that arises as the duration of exposure to the electromagnetic radiation and its dosage is increased. Using a computer simulation, a semi-classical model is adopted, were the photon-phonon interaction is mediated by a homogenous sample of identical elements, which are naturally in harmonic modes of vibration. The phonon lifetime is also included in this work. These thermal effects decrease with frequency in conformity with experimental results. This model is then extrapolated to the individual cells of a human tissue and the possible rise in temperature is estimated.  相似文献   

9.
Current evolution of wireless personal communications has necessitated a comprehensive understanding of electromagnetic interactions between handset antennas and nearby human body. In this work the handset–human body interactions were evaluated in various configurations (with and without user’s hand; with and without user’s head, and combinations of them) in order to obtain statistical averages of the overall performance for system link evaluations. The measurements were performed using the random-field measurement (RFM) method, and thus the acquisition of large amounts of data about human–mobile phone interactions in typical operating environment with measured the received RF signal strength (RXLEV), and the output power level (TXLEV) on mobile station. The RXLEV and the TXLEV was measured over the air interface in the networks on two Bulgarian GSM mobile operators (Mtel and Vivatel). Both uplink and downlink measurements were performed in urban area in three cities. Each measurements were carried out in a building included both line-of-sight and non-line-of-sight propagation of the electromagnetic waves between mobile station and base station. The results showed that the user’s hand and head induces more significant changes on the received RF signal strength in case when broadcast control channel (BCCH) levels are up to −60 dBm. Also the alterations of receiving RF signal strength and output power level of the MS are influence stronger from the larger size of the hand and head of user. The influence from presence of the head and hand of the subscriber in talk position over the alteration of the receiving RF signal strength is in boundaries from 14.21 dBm to 19.1 dBm (man) and from 8.5 dBm to 12.05 dBm (woman). The presence of the user’s hand and head increased the output power level of mobile station with 12 dBm to 14 dBm (man) and with 10 dBm to 12 dBm (woman) compare to output power level without user’s hand and head.  相似文献   

10.
In Korea due to rapid economical growth followed by urbanisation, breakage of large traditional families into small nuclear families, continuous changes in equipment features and capabilities causes tremendous increase in sale of new electrical and electronic equipment (EEE) and decrease in sale of used EEE. Subsequently, the ever-increasing quantity of waste electrical and electronic equipment (WEEE) has become a serious social problem and threat to the environment. Therefore, the gradual increase in the generation of WEEE intensifies the interest for recycling to conserve the resources and protect the environment. In view of the above, a review has been made related to the present status of the recycling of waste electrical and electronic equipment in Korea. This paper describes the present status of generation and recycling of waste electrical and electronic equipment, namely TVs, refrigerators, washing machines, air conditioners, personal computers and mobile phones in Korea. The commercial processes and the status of developing new technologies for the recycling of metallic values from waste printed circuit boards (PCBs) is also described briefly. Since 1998, three recycling centers are in full operation to recycle WEEE such as refrigerators, washing machines and air conditioners, having the total capacity of 880,000 units/year. All waste TVs are recently recycled on commission basis by several private recycling plants. The recycling of waste personal computers and mobile phones is insignificant in comparison with the amount of estimated obsolete those. Korea has adopted and enforced the extended producer responsibility (EPR) system. Korea is making consistent efforts to improve the recycling rate to the standards indicated in the EU directives for WEEE. Especially environmentally friendly and energy-saving technologies are being developed to recycle metal values from PCBs of WEEE.  相似文献   

11.
The environment in which biology exists has dramatically changed during the last decades. Life was formed during billions of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation and the terrestrial magnetism. The existing organisms are created to function in harmony with these forces. However, in the late 19th century mankind introduced the use of electricity and during the very last decades, microwaves of the modern communication society spread around the world. Today one third of the world’s population is owner of the microwave-producing mobile phones. The question is: to what extent are living organisms affected by these ubiquitous radio frequency fields? Since 1988 our group has studied the effects upon the mammalian blood-brain barrier (BBB) by non-thermal radio frequency electromagnetic fields (RF-EMF). These have been revealed to cause significantly increased leakage of albumin through the BBB of exposed rats as compared to non-exposed animals—in a total series of about two thousand animals. One remarkable observation is the fact that the lowest energy levels give rise to the most pronounced albumin leakage. If mobile communication, even at extremely low energy levels, causes the users’ own albumin to leak out through the BBB, also other unwanted and toxic molecules in the blood, may leak into the brain tissue and concentrate in and damage the neurons and glial cells of the brain. In later studies we have shown that a 2-h exposure to GSM 915 MHz at non-thermal levels, gives rise to significant neuronal damage, seen 28 and 50 days after the exposure. In our continued research, the non-thermal effects (histology, memory functions) of long-term exposure for 13 months are studied as well as the effects of short term GSM 1,800 MHz upon gene expression. Most of our findings support that living organisms are affected by the non-thermal radio frequency fields. Studies from other laboratories in some cases find effects, while in other cases effects are not seen. Our conclusion is that all researchers involved in this field have the obligation to intensify this research in order to reduce, or avoid, the possible negative effects of the man made microwaves!  相似文献   

12.
Heavy metal pollutants in soils can usually enter the human body and pose heath risks through a soil-crop-human body pathway (indirect exposure) or soil-human body pathway (direct exposure). Previous studies often neglected the direct exposure in human health risk assessment, especially for children. We collected surface soil samples from urban and suburb areas in Changsha City, China, to analyze the content ofAs, Cd, Hg, Ni, Pb, and Zn. A combination of principal component analysis, geostatistics, and triangulated irregular network (TIN) model was successfully used to discriminate the sources of heavy metals. The direct exposure method, sequential indicator simulation, and geographical information system (GIS) technologies were used to perform a health risk assessment of heavy metal exposure to children living in the study area. Results show that heavy metal contamination in Changsha may originate from coal usage and industrial activities. One thousand equiprobable realizations suggest that not all sites within the study area may be suitable for housing or allotments without remediation. Most high hazard indexes are located in the suburb and mining areas. Moreover, arsenic presents a high health risk in comparison with other elements. Compared with inhalation and dermal contact in direct soil exposure, soil ingestion is the largest contribution to potential health risks for children. This study indicates that we should attach great importance to the direct soil exposure for children's health.  相似文献   

13.
Monitoring the complex environmental relationships and feedbacks of ecosystems on catchment (or mountain)-to-sea scales is essential for social systems to effectively deal with the escalating impacts of expanding human populations globally on watersheds. However, synthesis of emerging technologies into a robust observing platform for the monitoring of coupled human-natural environments on extended spatial scales has been slow to develop. For this purpose, the authors produced a new cyberinfrastructure for environmental monitoring which successfully merged the use of wireless sensor technologies, grid computing with three-dimensional (3D) geospatial data visualization/exploration, and a secured internet portal user interface, into a working prototype for monitoring mountain-to-sea environments in the high Hawaiian Islands. A use-case example is described in which native Hawaiian residents of Waipa Valley (Kauai) utilized the technology to monitor the effects of regional weather variation on surface water quality/quantity response, to better understand their local hydrologic cycle, monitor agricultural water use, and mitigate the effects of lowland flooding.  相似文献   

14.
Summary This paper is a comparative study of several antennas commonly used in cellular telephones. These include a monopole, a helix-monopole and a patch antenna. Each one of these structures is modeled and numerically tested using finite-difference time-domain simulation and human models based on magnetic-resonance images, which allow for inclusion of details of the human body in the simulation. The testing procedure involves antenna simulation in the proximity of the human head. The behavior of each antenna is evaluated for variable distances from the head geometry (0, 1, 2, 4, 8 and 16 mm). Continuous waveform, representative of the sources used in mobile telephones, (250 mW, 1.8 GHz) is used as the form of the antenna excitation. The simulation outputs used as measures for this comparative study include transmitting and receiving antenna characteristics and the specific absorption rate (SAR). The SAR levels for the head tissues are calculated for and with accordance to the two currently accepted standards: Federal Communications Commission (FCC) and International Commission on Non-Ionizing Radiation Protection (ICNIRP). The computed SAR levels within each of the considered tissues vary for the three antennas under investigation and are within the determined health safety standards. Results suggest that the patch antenna may be the structure of choice when considering safety standards, as its radiation yields the lowest local SAR in the head tissues.  相似文献   

15.
ABSTRACT

High seas fisheries remain one of the least transparent global production practices. Distance from shore, coupled with the highly mobile nature of fish stocks, has put attention on new monitoring, control and surveillance technologies to collect spatially referenced data on the location of fishing vessels, gears and even fish stocks and eradicate illegal, unreported and unregulated fishing activity. Faced with their nascent implementation, research is yet to address how these technologies are reconfiguring the roles and responsibilities of public and private actors involved in fisheries management, including who collects and controls fisheries related information. In this paper, we compare three monitoring, control and surveillance technologies that are gaining traction in fisheries; the use of private fish attraction devices in oceanic tuna fisheries, unmanned public drones for marine surveillance and global satellite monitoring of fishing vessels. In doing so, we question how different configurations of actors are structuring flows of information and with what effect on sustainability performance of high seas fisheries. We also explore how these technologies configure new (and imagined) geographies of high seas fisheries which challenge existing modes of fisheries management.  相似文献   

16.
Occupational exposure to radiofrequency (RF) and static magnetic fields at magnetic resonance imaging (MRI) suites is of continuing concern to personnel who routinely work in this environment. Questions regarding the levels of occupational RF and static field exposure have increased with the increasing demand for anesthetics to be administered in this environment. The present study was thus designed towards addressing the above-mentioned problem by gaining information regarding exposure levels of clinical personnel at MRI units in South Africa. Three 1.5 MRI units in Bloemfontein, South Africa were utilized to evaluate the exposure of clinical personnel to the electromagnetic fields present in the MRI environment over a period of time and during different clinical MRI procedures. Three rounds of measurements of RF fields in the MRI environment were done. All the three measurement rounds were focused on the low frequencies, 5 Hz–32 kHz, as well as on the high frequencies, 300 kHz–40 GHz. First round measurements were done to establish the background of the RF fields in and around the magnet room during an MRI examination. Second round RF field measurements were done at a specific location, 1 m away from the bore on the right-hand side of the bed, in the MRI room. The third round measurements were of the same format as the second round, but the specific location was against the magnet bore. Two pieces of Narda Safety Test Solution instruments, the EFA-300 and EMR-300, were used to measure the electromagnetic and magnetic exposure fields generated from the MRI scanners. Results of the measurements indicate that the electromagnetic fields measured during different clinical procedures do not exceed the International Commission on Non-Ionizing Radiation Protection (2000) guidelines in these units. Results from round two and three showed that the RF and gradient exposure 1 m and up against the bore entrance does not exceed these guidelines (rms average over 6 min). Ongoing new developments in MRI scanning create the need for continuously monitoring exposure of patients and workers to the EMF fields in the MRI environment.  相似文献   

17.
本文结合重庆市空气质量限期达标规划编制案例,介绍了城市空气质量达标规划编制中的几个关键技术及其具体应用,包括本地化污染源排放清单编制、污染物来源解析、污染物排放形势预测与减排潜力分析以及大气环境容量核算等。本地化污染源排放清单是城市空气质量达标规划编制的基础,针对现有污染源制定科学合理的减排方案是达标规划的核心内容。分析不同区域的污染物组分浓度特征、污染源贡献以及未来污染排放形势预测,有助于识别出制约未来空气质量达标的关键因素及污染源。基于污染源减排潜力和污染传输矩阵制定的污染源减排方案更具合理性和可行性,应用空气质量模型估算大气环境容量可为规划目标可达性提供依据。  相似文献   

18.
This study focused on the determination of the toxic metal content of Liquid Crystal Displays (LCDs) present in various Waste Electrical and Electronic Equipment (WEEE). The main objective was the identification and quantification of toxic metals detected in LCD panels. An experimental procedure which involved dismantling, shredding, pulverization, digestion and chemical analysis was followed for the sorting, separation and analysis of LCD monitors from various electronic devices that are currently on the market. Nine selected devices were examined, originated from four different types of e-waste (WEEE); TVs, computers, mobile phones and tablets. Eleven metals were measured in all examined samples. In addition, concentration values of chromium (Cr), cadmium (Cd), lead (Pb) and mercury (Hg) were compared with the respective limits set by the RoHS 2002/95/EC Directive that was recently renewed by the 2012/19/EU recast. The comparison revealed that the examined toxic metals on LCD panels did not exceed the limits set by the European Union (EU). Furthermore, when results were compared to the TTLC regulatory limits it was revealed that in three samples As concentrations were higher than the limit. Finally, when the TCLP test was implemented the aforementioned samples did not exhibit proportionally elevated values in their leachates.  相似文献   

19.
Summary This paper reviews the emission sources of oxides of nitrogen and provides an estimate of the contribution from the Greater Manchester conurbation. The uncertainty attached to the estimate is large. Atmospheric and rainwater concentrations of oxides of nitrogen are reported from the Greater Manchester Acid Deposition Survey network. The health and ecological implications of these concentrations are commented upon and the measured values compared to a number of environmental guidelines, including recently formulated critical load and critical level estimates. Control technologies applicable to both mobile and large combustion sources are briefly reviewed.Dr James Longhurst is Director of the Acid Rain Information Centre which is based at Manchester Polytechnic.  相似文献   

20.
High frequency electromagnetic fields (EMF) are widely used for transmitting of radio and TV signals, in wireless communications, etc. A huge number of people are exposed so the possible risk to human health from telecommunication technologies could be significant even if biological effects are slight. The study of the biological effects of RF EM radiation could contribute to better understanding of the possible health hazards. The levels of released hemoglobin serve as an indicator of hemolysis, caused by increased membrane fragility. This study was designed to investigate the alterations in hemoglobin release after in vitro exposure of human erythrocytes to GSM900 electromagnetic field. Erythrocyte suspensions with two different cell concentrations (hematocrit 20% and 40%) were exposed to EM radiation from GSM mobile phone (carrier frequency 902 MHz, 2 W output power in pulse) for 20 min in two different positions in relation to telephone antenna: Position 1 is in the centre of the major lobe of the azimuth antenna pattern and Position 2 is between major and back lobes. Alterations in hemolysis were registered 0, 10, 20, 30, 40, 50 and 60 min after the treatment. Hemolysis was determined by measuring the absorbance of hemoglobin at 413 nm in the supernatant obtained by centrifuging the suspensions. Hemolysis was expressed as hemoglobin concentration. Our data indicated decrease in the hemoglobin level in irradiated suspensions. The GSM900 EMF exposure probably stabilized erythrocyte membrane and caused reduction in the hemolysis depending on the EMF parameters, on the suspension water content (hematocrit) and on the time elapsed after irradiation.  相似文献   

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