• 论文 •

### 我国食管癌典型病区的地理环境分析

1. 河南省科学院地理研究所
• 出版日期:1982-07-20 发布日期:1982-07-20

### AN ANALYSIS OF THE GEOGRAPHICAL ENVIRONMENTS OF TYPICAL AREAS OF ESOPHAGEAL CANCER IN CHINA

Guan Shukui, Fa Nailiang

1. Institute of Geographg of Henan
• Online:1982-07-20 Published:1982-07-20

Abstract: In this paper,we have analysed the factors of the geographical environments, such asgeology,geomorphy,climate,soil,drinking water,and vegetation.The primary results have been obtained as below: In North China,the areas of high incidence rate are located on top of the layer of Permo-carboniferous period.In the coal bed,there is nitrogen which can form nitrosamines,but in the areas of high incedence rate of Sichuan Province, there is no such layer.This is something still should be studied. In the regions of low mountains and hills,and inclined plains,the mortality rates of esophageal cancer are the highest.As one moves away from these regions, the mortality rate will decrease.This variation in mortality rates seems to have some relation with the geomorphic features. These areas of high incidence rate are mostly located at regions of the subarid and subhumid climate which have relatively arid and warm environments (refer to moisture and heat).Taking the northern areas of esophageal cancer in Sichuan Province for instance,it has been found that the farther away from the central region with a high incidence rate of esophageal cancer,the more rainfall and the less arid it is,and the mortality rate of esophageal cancer decreases. In the drinking water and soil in these regions with a high incidence rate, there are nitrites and nitrates which are the precursor compounds of nitrosamines of carcinogenic substance.This phenomenon coincides with the meteorologic conditions of the subarid and subhumid regions and the contents of the trace elements such as molybdenum,copper,manganese,zinc are correspondingly lower than that for areas of low incidence rate.Among these elements,the low content of molybdenum is most obvious. Under the geomorphic features of low mountain and hill regions and the environments of the subarid and subhumid climate,the local masses of these areas of high incidence rate like pickled vegetables ,a local favorite food,This food has been identified that these pickled vegetables cooperated with the action of fungi produce strong carcinogen,