Health Hazards among Children in Air-Polluted Districts

Abstract

Many reports have revealed that the prevalent rate of bronchial asthma among schoolchildren, as well as among aged residents, is closely related to the degree of regional air pollution in Japan. Recent findings of epidemiological, clinical, and immuno-pathological studies have demonstrated the close relationship between bronchial asthma and recurrent respiratory infection, which is regarded as a precursor of childhood asthma. To prevent these diseases in childhood and to improve health conditions, it is necessary to investigate precisely the association of these health hazards in airpolluted districts.We obtained 5, 283 schoolchildren's respiratory symptoms in three air-polluted districts by means of questionnaires. Five hundred and fifty three of these children were tested clinically for bronchial asthma. We also investigated the influence of the housing environments on asthmatics in a highly polluted district.The results are as follow:1. Subjective symptoms of a higher specificity rate in those diagnosed as asthmatics are wheezing with orthopnea in the past 2 years, diagnosed as asthmatic by a doctor in the past, and wheezing with orthopnea in the past 2 years, In contrast, those of a higher sensitivity rate are wheezing only in the past 2 years, and wheezing with slight dyspnea in the past 2 years.2. Asthmatic children have various complaints of the upper-and lower-respiratory tract, such as cough, phlegm, breathlessness, recurrent respiratory infection, and nasal trouble. In a comparison of sex-and school year-matched groups, a close relationship was found between bronchial asthma and recurrent respiratory infection or the so-called “frequent colds”.3. Case-control studies reveale the influence of dwellings and environment on asthmatic children. A retrospective study showed that their influence was not remarkable in the years of high-grade air pollution, but a follow-up study from 1976 to 1977 showed a major influence with lower-grade air pollution. Dwellings and their environment has been shown to be an indicator of the socio-economical situation of each house hold by many other authors. As air pollution these days is becoming less concentrated but widespread in Japan, it must be noticed that the health of the children in industrial districts is influenced by many socio-economical factors as well as by air pollution, itself.