The Study Of The Effects Of Extremely Low Frequency Electromagnetic Fields In Urban Environment On The Nervous System And The Hematological System

Objective: To learn the level and characteristics of extremely low frequency electromagnetic fields in modern city residential environment. And to research extremely low frequency electromagnetic field may affect human nervous system and the hematological system.Methods: Select one university in Chongqing city which have one old campuse located in urban district and one new campuse in suburb. Extremely low frequency electric field and magnetic field intensity are measured respectively in and out of students'dormitories from two campuses. To select randomly 257 students from two campuses, 132 students are from the old campuse and 125 students are from the new campuse. Using the unified questionnaire, each students make face-to-face questionnaire. WHO neurobehavioral core test (WHO-NCTB ) includes seven tests, only six tests were used in this time. Strictly according to the requirements and order of WHO-NCTB, performing neurobenhavioral function tests and examining general hematology test at the same time. Results: According to the guidlines of the International Commission on Non Ionizing Radiation Protection (ICNIRP 1998), all measured values did not exceed the limits of the guidelines. The mean values of magnetic fields of 5Hz~1kHz both in and out dormitories from old campus were higher than those from new campus(P<0.05).The positive rate of nervous system symptoms is higher, including drowsiness and hypodynamia, excessive dreams, dysphoria, irritable, depression, the memory decrease, sweating, loss of hair and decreased eyesight. Hypodynamia and excessive dreams from old campus were higher than those from new campus(P<0.05). There is one significantly difference in six neurobenhavioral function tests, whose the average standard score of the old campuse is lower than that of the new campuse(P<0.05). There are 11 indexes from 16 indexes have significantly difference statistically in the general hematology test(P<0.05).Conclusion: The main frequency of 5Hz~1kHz is power frequency(50/60Hz). The outdoor level of magnetic fields in old campuse is higher than in the new campuse mainly due to more outdoor transmission lines. The indoor level of magnetic fields in old campuse is higher than in the new campuse. Except for high outdoor magnetic field may effect the indoor magnetic fields, there are more electric appliances in the old campus dormitories. Extremely low frequency electromagnetic fields may have some effect on the nervous system, and also can influence human hematological system.