【作者】 吴锡南；

【导师】 程天民；

【作者基本信息】 第三军医大学 ， 军事预防医学， 2002， 博士

【摘要】 随着科学技术的发展，电磁波(EMF)对人类健康的影响日益受到关注。一些资料表明：癌症、行为改变、记忆力丧失、帕金森氏综合症和Alzheimer病及其它一些疾病被认为与EMF暴露有关。当前世界上的每一个人都处在0-300GHZ频率的复合EMF暴露中，EMF已成为最广泛和增长最快的环境影响因素之一。移动电话通讯信号是一种低强度的射频电磁波(RF-EMF)，近期发展数字式移动电话天线平均输出功率小于早期的模拟式移动电话，但是最大输出功率比后者要大，辐射的模式不同。移动电话及其基站所发射的低强度RF的生物效应研究，对识别、确认其可能的健康危害、制定或修订国际和国家有关卫生标准、采取必要的防护措施均具有重要意义。因此，WHO电磁波研究计划的目标之一，是评估移动电话技术造成的RF电磁波辐射可能引起的与中枢神经系统有关的健康危害。为此，我们进行了本项研究，期望对这种评估提供实验依据。 作为低强度射频电磁波的移动电话通讯技术，如能导致生物效应，也可能是轻微的，因此必须选择能够反映这些轻微变化的敏感指标来进行研究。本实验选择的指标及其理由是： 1．生殖和发育：生殖过程对毒性因素影响特别敏感。毒性刺激能阻断细胞的减数分裂、受精和植入过程。发育中的细胞快速分裂和分化，使细胞尤其容易受到攻击。在一定的暴露水平条件下，已知某些药物和环境公害因素对成年动物没有危害或危害较小，但能引起胚胎或胎儿的致畸效应。因此，检测RF生物效应是否影响动物的生育能力和发育非常重要。 二．行为功能：动物中枢神经系统功能的早期发育尤其容易受到影响。潜在有害因素的刺激，早期体征常常表现为行为改变而不是解剖学异常，行为功能己经成为评估健康危害的敏感指标，动物行为实验通常作为研究学习和记忆的生物学基础。 3．诱导海马脑片突触传递长时程（LTP）和海马脑区超微结构：动物的学习和记忆能力与海马有关。海马损伤将干扰学习过程，引起海马神经细胞间突触连接传递效率发生快速持久的改变，而突触连接构成了记忆痕迹的细胞基础。己有实验表明海马脑片对RF效应的研究显示了巨大的潜力。 4，潜在的遗传毒性：RF电磁波遗传毒性研究对补充与人类有关疾病的流行病学证据非常重要。 基于以上的原因，本实验研究下列内容：生殖和发育观测：认知功能测试：诱导海马脑片突触传递长时程增强；海马脑区超微结构观察；董星实验检测外周血淋巴细胞DNA的损伤；骨髓嗜多染红细胞微核形成实验；精子畸形观察。该实验是在作者以往工作的基础上进行的。作者于 1996年 5月一1998年 1月在德国国家环境与健康研究中心毒理研究所观察了大鼠出生前暴露 900MHz，功能密度为 0．lmw儿（217Hi调频人 每天 24小时连续对天脉冲波对行为功能的影响，结果显示：未发现暴露对大鼠中枢神经系统功能早期发育的损伤。 实验的暴露条件是：1800MHZ－RF（CW），远场功率密度分别为 0．5或 1．omw儿m’电磁波，大鼠出生前暴露，每天 24小时，连续ZI天：出生后暴露，每天门小时，连续对天。暴露方式的确定是基于以往实验的基础上，增强暴露的功率密度至 0．5或 l．offiw七，观察更高暴露条件下是否会产生生物效应；移动电话固然多是间断使用头部照射，但更多比例的暴露由其基站发出，属全身连续辐射。故本实验采用 24或 12小时连续全身暴露。 Vll 本实验在国内首次运用自动化操作行为测试系统和Moms水迷宫行为 图象自动采集和处理系统，结合研究学习记忆的电生理方法一突触传递长 时程增强（LTP）现象，对大鼠学习和空间记忆能力进行了较全面的观测。 通过低强度 1800MHZ－RF（CW）暴露对大鼠行为功能和遗传毒性的研究主 要结果如下： 1．出生前暴露 ＊）大鼠生殖和发育的影响：早期行为发育状况除“听觉惊愕”外，没有发现暴露对孕鼠生殖过程和 FI代仔鼠发育影响的其它证据。 p）自动化操作行为测试：FI代仔鼠口0周龄）在高频度差异强化期DRHS／4程序，实验1组雄鼠学习成绩较其对照和实验＊组低，似乎存在一个非线性特征；但是，动物在最初DRH刃1或最终D nnl门2程序学习中并没有表现出其操作行为功能存在组间差异；大鼠明暗识别学习能力各组间也没有显著性意义。 ＊）Moms水迷宫测试：Wng和 Lai以及 Sienkiewicz曾于 2000年报道运用迷宫研究低强度RF亲代大鼠或小鼠暴露对学习记忆影响，本研究首次应用＊＊is水迷宫行为图象自动采集和处理系统检测了出生前暴露h代仔鼠（10周龄）的认知功能。结果显示没有证据表明暴露对动物学习和空间记忆能力产生影响。 K）海马脑区的超微结构观察：神经细胞和毛细血管未见异常，有些暴露动物见有毛细血管周围轻微水肿，但这也见于一些对照大鼠。全部材料未见神经细胞调亡坏死等病变。没有观察到明显的证据说明暴露能导致大鼠海马的超微结构异常。 2．出身后暴露 （1）没有发现暴?更多还原

【Abstract】 New telecommunications technologies have been introduced without full provision of information about their nature and without prior discussion within the scientific community about possible consequences for health. The average output power from the antennas of digital mobile phones is lower than that from earlier analogue models, but the maximum powers are greater, the exact patterns of radiation are different and these differences might influence their effects on people. As the costs of mobile phone technology have fallen, their use has increased dramatically and the overall levels of exposure of the population as a whole have therefore increased. Potential effects of exposure to radiofrequency and other electromagnetic fields are causing significant public and occupational health concerns and need scientific clarification. Electromagnetic fields (EMF) represent one of the most common and the faster growing environmental influences in our lives, about which anxiety and speculation are spreading. Health effects such as cancer, changes in behavior, memory loss, Parkinson’s and Alzheimer’s diseases, and many theirs, have been suggested as resulting from exposure to EMF.Our experiment was motivated by research needs as defined by the World Health Organization(WHO), to clarify potential health risk of EMF’s presented by cellular telephone technology. Appropriate endpoints for this study were determined by following arguments:Firstly, Many of the process associate with reproduction are especially sensitive to toxic influences. Meiosis, fertilization and implantation of the embryo can all be disturbed by toxic insults. The high rates of cell division andIIdifferentiation in the developing fetus make it particularly vulnerable. It is therefore important to assess the possible effects of RF fields on fertility and development. Secondly, Functional or behavioral changes in an organism often occur prior to structural changes. Functional changes in the central nervous system(CNS) are among the earliest to become observable. Furthermore, the sensitivity of CNS-functions to interfering agents during development has been demonstrated many times in animals and human beings. Thirdly, more research is indicated that the hippocampal slice preparation shows great potential for the study of RF field effects. Fourthly, studies of the genotoxic actions of RF radiation have been of value in supplementing epidemiological evidence about human disease.To address and assess health risks in rats after prenatal or postnatal exposure to low level RF-EMF, the experiments were performed as below:Reproduction and development effects;Cognitive function changes;Induced long-term potentiation (LTP)in the hippocampal slice preparation;Ultrastructural observation in the hippocampus;DNA damage in peripheral blood lymphocyte;Micronucleus formation in polychromatic erythrocytes in bone marrow;Abnormality of sperm in adult male animals.Taken together, there is almost no experimental evidence that prenatal exposure to low level RF field affects fertility, development, learning, spatial memory and hippocampal ultrastructure in rats; DNA damage experiment have produce clear evidence that postnatal RF radiation is genotoxic at non-thermal levels in peripheral blood lymphocyte, but there is a absence of positive result coming from observation of micronucleus formation in polychromatic erythrocytes in bone marrow. Furthermore, no findings of hippocampal slices induced LTP exist statistically significance in between groups. Conclusion forinour study were assessed by following reasons:1. Prenatal exposure to low density RF-EMF(1) Differences between field-exposed and sham-exposed dams or offspring were not found in litter size, the evolution of body mass, the developmental landmarks, or abnormality of sperm. However, the difference in only auditory startle reflex of different groups in 6 behavioral developmental parameters was revealed to be affected as a result of increase slightly in pow更多还原