Fine dust is more harmful than previously thought
The particulate matter pollution can become a serious problem for people living in large cities. Especially if they are exposed to a higher concentration over a longer period of time, the risk of lung cancer increases considerably. An international research group has investigated to what extent which diseases in relation to air pollution from fine dust develop. The two Ulm scientists Gudrun Weinmayr and Professor Gabriele Nagel from the Ulm Institute for Epidemiology and Medical Biometry made a significant contribution.
In total, the data from 17 European cohort studies with a total of over 300,000 subjects were evaluated. For their analysis, the scientists also used the data from cancer registries and were able to examine the effects over a longer period of time. The results of the study entitled “European Study of Cohorts for Air Pollution Effects” (ESCAPE) have now been published in the specialist journal “The Lancet Oncology”.
The air pollution caused by fine dust in large cities is primarily man-made and arises from combustion processes in motor vehicles and power and district heating plants, stoves and heating systems in residential buildings, and in the production of metal and steel. The sulfur and nitrogen oxides formed together with ammonia result in the so-called “fine dust”. In nature there is also a natural formation, for example as a result of soil erosion. In the metropolitan areas, road traffic is one of the main causes of fine dust. The small size of the fine dust particles means that they are more easily absorbed through the airways and thus enter the bloodstream. The health effects that can be caused by fine dust include cancer, asthma, allergies and cardiovascular diseases.
Data from cancer and mortality registries were used. For the study, special measuring stations were set up in the study centers, which are spread all over Europe, so that the researchers could determine the average concentration of fine dust as precisely as possible. The two scientists from the Ulm Institute evaluated the data from Vorarlberg, the westernmost state of Austria: "Based on the measurement data, we calculated a so-called land use model and were thus able to quantify the average air pollution over several years for the addresses in the examined area," explains Gudrun Weinmayr. To make the results as meaningful as possible, the data were compared with the local cancer and mortality registry. Any existing confounding factors such as smoking, diet and social status have also been taken into account in the statistical analysis. The study came to a clear result. Even fine dust concentrations that are significantly below the European limit increase the likelihood of developing lung cancer.
Lung cancer was diagnosed in 2095 people during the 13 years of the study. The so-called aden carcinoma occurred particularly often in the test subjects, which also occurs increasingly in non-smokers. According to the study, an increase in the concentration of PM10 particles by ten micrograms already increases the risk of lung cancer by 22 percent.
A reduction in fine dust levels is worthwhile In the course of the study, 29,000 of the test persons died. According to the study, the probability of death increased by seven percent if the fine dust pollution increased by five micrograms per cubic meter. “However, we cannot set a threshold value for a health risk from fine dust. In general, even below 40 micrograms per cubic meter: "The less, the better," say Gudrun Weinmayr and Gabriele Nagel. The results of the study show that a reduction in the fine dust concentration, regardless of the value, is always worthwhile in terms of the health of people in large cities. (fr)
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