Scientists have found a connection between car noise, dirty air and high blood pressure
If you constantly have to complain about the dirty air in your area and the noise of cars outside the window, there is a high risk that you will face hypertension in the future. This is the conclusion reached by researchers who have analyzed data for more than 41 thousand people in five countries of the world for nine years.
The results of this large-scale study were published in the European Heart Journal on October 25th. They showed that every hundredth person living in a dirty area develops arterial hypertension . Noise and dirty air give the same risk as overweight in a person whose body mass index (BMI) is in the range of 25-30. Researchers note that high blood pressure is one of the most important risk factors for premature illness and death.
This study is the first of its kind, at the same time studying the effects of dirty air and traffic noise on people's health. Researchers have found that traffic noise is associated with an increase in the number of hypertensive patients. They also rated the risks associated with noise, separate from the dirty air.
In total, 41,072 people from Norway, Sweden, Denmark, Germany and Spain took part in the study. It has become part of the ESCAPE (European Study of Cohorts for Air Pollution Effects) project , which studies the long-term effects of dirty air on human health in Europe. At the first stage, volunteers reported information about the state of pressure. When they joined the study, none of them suffered from high blood pressure. In subsequent years, all participants underwent regular surveys. After analyzing the data, scientists estimated that of all volunteers, 6,207 people (15%) were diagnosed with arterial hypertension. They were prescribed medication to lower the pressure.
In 2008-2011, the level of air pollution was measured near the houses of participants. The process was divided into three two-week periods, taking into account seasonal effects. Scientists used special filters to collect information about pollutants - solid impurities in the atmosphere (TM). Such particles can be of different sizes. For example, PM10 is particles smaller than or equal to 10 µm in diameter. Similar to PM2.5 (less than or equal to 2.5 microns). There are also coarse PM (PM10 minus PM2.5) and PM 2.5 optical density (soot particles). Particulate matter was analyzed in 20 plots of each country. The concentration of nitric oxide was determined in another 40 different zones with regression of land use. As for traffic noise, the density of traffic flow and the hum near the houses of the participants did not exceed the limit set by the EU Directive .
The researchers found that in those areas where the concentration of PM2.5 is 5 µg / m3, the risk of hypertension is increased by 22% compared with cleaner areas. Higher concentrations increase the likelihood of getting sick. For residents of houses, where the average noise level on the street at night reaches 50 decibels, the risk of cardiovascular diseases is increased by 6%. For comparison, conversational speech ranges from 45 to 60 decibels, depending on the volume of the voice, and the noise of heavy traffic often does not exceed 80 decibels. From this we can conclude that the potential susceptibility to cardiovascular diseases is even where the noise level does not exceed the permissible rate established by the EU directive. In Russia, the permissible noise rate at night is limited to 30 decibels.
This is a very important aspect, since the current legislation does not protect the population of Europe from the adverse effects of traffic noise. Scientists believe that research results are important for public health and require the introduction of more stringent restrictive norms.
It is known that when a person is busy with something, prolonged noise exposure reduces concentration and increases the likelihood of making mistakes. In addition, noise can disrupt the metabolism, adversely affect the nervous system, lead to the occurrence of ulcers and other diseases. Too loud noise (more than 100 decibels) leads to rupture of the eardrum. As a result, the hearing is either greatly reduced, or deafness occurs.
According to the study, the “leaders” in traffic noise and traffic density were areas of Sweden and Spain. The highest average level of pollution is observed in Central and Southern Europe - Germany and Spain. In Norway, Sweden and Denmark, the streets are quieter.
Professor of Environmental Epidemiology at the University of Dusseldorf. Heinrich Heine Barbara Hoffman, who conducted the analysis, confirmed that prolonged exposure to particulate contaminated air is associated with an increased incidence of hypertension. And since almost all of us are exposed to the dangerous influence of dirty air during our life, the risk of earning health problems is quite large.
There is a possibility that dirty air and noise have a different effect on the normal functioning of the body, or only partially coincide. Possible biological consequences of the negative effects of dirty air on the functioning of the heart vessels and blood vessels include local and systemic inflammation, oxidative stress and disorders of the nervous system.