| Objective: To measure and investigate the 900~1900 MHz electric field strength and composite power density in urban residential environment. To learn the level and characteristics of electromagnetic radiations, then analysis the possible reasons that make electromagnetic radiations like this level. And through a crowd Epidemiology into 900～1900MHz electromagnetic radiations may affect the tell symptom of nervous system and the hematological system and research the impact of the blood corpuscle.Methods: (1)To select one university which have one old campus and one new campus in Chongqing city to be the experiment set and matched set respectively. The old campus is located in prosperous district in the city center, and the new campus is located in suburban district. To measure respectively the 900~1900 MHz electric field strength and composite power density in the door and out the door. (2)To select randomly 130 students from the old campus qua the experiment set and to select randomly 119 students from the new campus qua matched set .We totally selected 249 persons from two campuses.(3)Adopting the investigation questionnaire of WHO recommend make uniform designing and printing, make face-to-face the site questionnaire with each one.(4)Requested them to complete the WHO-NCTB at the same time, with inspecting the neurobehavioral function status of the testee.(5)Then collected the finger tip blood of the testee , to do blood routine test.Results: (1)The maximum of the general electric field strength and composite power density are 1.23±0.18 V/m and 8.57±7.34μW/cm~2 in old campus. The maximum of the general electric field strength and composite power density are 0.95±0.06V/m and 3.34±3.13μW/cm~2 in new campus. According to the guidelines of the International Commission on Non Ionizing Radiation Protection (ICNIRP 1998) and State Environmental Protection Administration promulgated the "standard of environmental electromagnetic waves"(1988), there was not any value which exceeded the limits of the guidelines. The mean values of electrical field strength and composite power density of 0.7～3GHz,0.1～3000MHz and 1MHz～40GHz both in and out dormitories , the measured values of the new campus indoor and outdoor were obviously lower than those from the old campus(P<0.01).(2)The results of the questionnaire display that the masculine gender's from the new campus are lower than those from the old campus: doze-off, myasthenia of limbs, insomnia, dreaminess and doubt that oneself is sick. The experiment set is higher than the matched set(P<0.05).But the results of the questionnaire display that the masculine gender's from the old campus are not higher than those from the new campus: bleeding nasal, bleeding gums, petechia , hypermenorrhea(P>0.05). the results of the questionnaire display that the masculine gender's from the male are higher than those from the female in old campus: difficulty falling asleep, irascibility, lose one's hair, resistibility descending(P<0.05),there are not evidently difference among the male and the female in new campus. (3)There is only one average standard score in six neurobehavioral function tests of the testee from new campus is higher than that the from old campus: digit span, and there is a significantly difference among the old campus and the new campus (P< 0.05) . (4)To do blood routine test, we detected that there are 3 indexes from the old campus in 18 detecting indexes are higher those from the new campus and there are 7 indexes from the old campus in 18 detecting indexes are lower those from the new campus. There are significantly differences on the 10 indexes among the old campus and the new campus (P< 0.05 ).Conclusion: (1)The causation that the measured values of the 900~1900 MHz electric field strength and composite power density in the door and out the door in new campus lower than those in old campus may be that there are several small mobile database stations on the top of building in old campus(.2)But the results of the investigation questionnaire display that the tell symptoms of nervous system may be affected by 900~1900 MHz electromagnetic radiations. The female may be more easily affected in those aspects than the male. But the evidence is not adequate. There have not detected any difference on the tell symptoms of the hematological system in this investigation questionnaire. This indicated that the evidence on 900~1900 MHz electromagnetic radiations effected on the hematological system is not adequate.(3)The significantly difference of average standard score of the"digit span"in six neurobehavioral function tests of the testee display 900~1900 MHz electromagnetic radiations may affect the capability of audition to stay memory of the testee. (4)The significantly differences on the 10 indexes among the old campus and the new campus display 900~1900 MHz electromagnetic radiations may affect the blood corpuscle of human hematological system .
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