Studies of Non-Ionizing Radiation-Related Cancer

为了解决人们对住宅磁场暴露的癌症风险的广泛关注，NCI和儿童癌症小组的研究人员对儿童急性淋巴细胞白血病进行了一项病例对照研究。最近的分析集中在暴露度量的方法学问题上，并得出结论，静态磁场的重复现场测量将有必要将受试者的卧室分类为“共振”或“共振”，但单点测量是不够的。此外，还测量了电器的磁场，以确定与儿童白血病有统计学联系的特定类型的电器是否实际上产生了更高的磁场暴露。这些电器的磁场没有足够的升高来解释统计学上的关联。 脑肿瘤的病因学知之甚少，在过去的几十年中，记录的发病率急剧增加。这种增加是部分真实的还是完全是诊断改善的假象是一个有争议的问题。尽管如此，人们还是担心一种或多种越来越常见的环境暴露可能会导致脑癌。例子包括工业化学品、杀虫剂、食品添加剂和电磁场。为了回应这些担忧，并进一步了解脑肿瘤的环境，行为和遗传原因，我们正在与美国三家医院的研究人员合作，对恶性和良性脑肿瘤进行病例对照研究。考虑的因素包括工作场所暴露于化学制剂和电磁场、使用移动电话、饮食因素、肿瘤家族史、易感性的遗传决定因素、家用电器使用、生殖史和激素暴露、病毒、医疗和牙科暴露于电离辐射以及病史的其他方面。该研究的主要特点包括其规模大，强调快速确定事件的情况下，研究对象，而不是替代受访者的采访，使用详细的，由工业卫生学家开发的特定于工作的问题，以确定职业暴露，和血液样本的存储为未来的遗传易感性，暴露的生物标志物，基因-环境和基因-基因相互作用的评估。我们的初次报告涉及移动电话的使用。我们没有发现手机使用与脑肿瘤有关联。 针对微波和无线电频率的非电离辐射引起的癌症风险问题，重新启动了一项关于朝鲜战争海军服役退伍军人暴露于微波辐射的癌症死亡率的早期研究。所有疾病和所有癌症的死亡率都明显低于预期，与雷达暴露潜力较低的20，000名水手相比，雷达暴露潜力高的20，000名水手的死亡率明显低于预期。在朝鲜战争期间，雷达照射似乎没有对健康产生不利影响。

To address widespread concerns about cancer risks from residential magnetic field exposures, investigators from NCI and from the Children's Cancer Group have conducted a case-control study of childhood acute lymphoblastic leukemia. Recent analyses focused on methodologic issues of exposure metrics, and concluded that repeated spot measurements of static magnetic fields would be necessary to classify bedrooms of subjects as being "in resonance" or "out of resonance", but that a single spot measurement was insufficient. In addition, magnetic fields from appliances were measured to determine if specific types of appliances, statistically linked with childhood leukemia, actually generated higher magnetic field exposures. Magnetic fields from these appliances were not sufficiently elevated to account for the statistical associations. The etiology of brain tumors is poorly understood, and recorded incidence rates have increased dramatically over the past several decades. Whether this increase is, in part, real or is entirely an artefact of improved diagnosis is a controversial issue. Nonetheless, concern has arisen that one or more increasingly common environmental exposures might cause brain cancer. Examples include industrial chemicals, pesticides, food additives, and electromagnetic fields. In response to such concerns, and to advance understanding of environmental, behavioral and genetic causes of brain tumors, we are collaborating with investigators at three U.S. hospitals in conducting a case-control study of malignant and benign brain tumors. Factors under consideration include workplace exposures to chemical agents and electromagnetic fields, use of cellular telephones, dietary factors, family history of tumors, genetic determinants of susceptibility, home appliance use, reproductive history and hormonal exposures, viruses, medical and dental exposure to ionizing radiation, and other aspects of medical history. Key features of the study include its large size, the emphasis on rapid ascertainment of incident cases and interview of study subjects rather than surrogate respondents, the use of detailed, job-specific questions developed by industrial hygienists to ascertain occupational exposures, and the storage of blood samples for future evaluation of inherited susceptibility, biomarkers of exposure, and gene-environment and gene-gene interactions. Our initial report concerned use of cellular telephones. We found no association of cellular telephone use with brain tumors. In response to concerns about cancer risk from non-ionizing radiation of microwave and radio frequencies, an earlier study of cancer mortality among Korean War Naval Service veterans exposed to microwave radiation has been reactivated. Deaths from all diseases and all cancers were significantly below expectation overall, and for the 20,000 sailors with high radar exposure potential compared to the 20,000 sailors with lower radar exposure potential. No adverse health effects appeared attributable to radar exposure during the Korean war.