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The World Health Organization (WHO) estimates that the contribution of non-medical factors (the contribution of environmental factors to morbidity) to health status is 20-30% and determines almost 10% of all deaths and disease burden worldwide[1]. Chief among the non-medical factors are air quality and climate change.
Air pollution is recognised as a global health priority. The continuing impact of polluted air on public health is ultimately reflected in rising rates of morbidity and mortality and mental health. This is primarily an increase in chronic respiratory diseases and the mortality rates associated with these diseases, as well as an increase in mortality due to various cardiovascular diseases. The WHO[2] estimates that every year air pollution causes 7 million premature deaths and the loss of millions more healthy years of life.
Russian scientists from the I.M. Sechenov First Moscow State Medical University have established that technogenic pollution aggravates the course of infectious and parasitic diseases. Before 2000, the environmental factor was not taken into account in assessing the development of infectious diseases.
In general, an acute and chronic impact of pollutants on health is distinguished. Acute exposure refers to various reflex reactions resulting from short-term exposure to a place with a high concentration of a pollutant (minutes), while chronic exposure reflects exposure over a period comparable to a person’s lifetime (years). Acute exposure is most often observed at very high levels of contamination, possible especially in enclosed spaces, while chronic exposure is also possible at quite low concentrations that can be observed in the atmospheric air. In chronic exposure, carcinogenic and non-carcinogenic effects are distinguished, and carcinogenic and non-carcinogenic substances respectively.
To reduce the potential adverse effects of air pollution, target levels or maximum permissible concentrations of pollutants are set, higher for one-time, acute exposure (in the RF, within 20-30 minutes) and lower for chronic exposure (years). At the same time, for some substances there are (determined by scientific methods) thresholds of safe exposure, and for some there are no such thresholds, and the standards for them are set based on the assessment of permissible or target levels of health risks.
According to the International Agency for Research on Cancer of the World Health Organization[3], of a total list of 1035 classified agents, 122 are currently recognized as carcinogenic to humans (Group 1), 93 and 319 as probably and possibly carcinogenic (Groups 2A and 2B) and 501 as unclassifiable as carcinogenic to humans (Group 3).
Group 1 includes, for example, tobacco smoke and diesel exhaust.
Among the non-carcinogens, suspended particulate matter PM10 and PM2.5, nitrogen dioxide and ozone (the first two largely of anthropogenic origin, while ozone is mostly natural) are the priority substances in terms of health. Scientific studies confirm that particulate matter is the largest contributor to the overall health risk from air pollution.
When PM10 concentrations are increased by 10 µg/m3 for two months, there is a 4.2% increase in the frequency of asthma attacks in children. Reporting or hospitalization for respiratory disease increases by 0.5% to 3.4% for every 10 µg/m3 of PM10 when exposed over a 24-hour period. This is particularly true for persons over 65 years of age[4]. The degree of atmospheric pollution depends not only on the amount of emissions of harmful substances and their chemical composition, but also on meteorological conditions determining the transport, dispersion and transformation of emitted substances. The main meteorological factors forming the level of air pollution include wind speed, wind direction and temperature regime, especially temperature distribution with altitude. On windless nights, ground-level inversions can form, which prevent the atmosphere from self-purification by vertical air currents. Such conditions for accumulation of pollutants and general growth of air pollution are almost always formed under conditions of temperature anomalies — abnormal heat and cold.
An example of increased air pollution in Moscow is the summer of 2010. An anticyclone in the region prevented pollutants from dispersing into the atmospheric air, and additional amounts came from fires. According to a study conducted by the Karolinska Institute together with leading Russian epidemiologists, the risk of additional daily deaths in Moscow due to air pollution and high temperatures was 11 thousand additional cases, or 11% [5]. It was shown that abnormal air pollution during that period contributed 30% to the negative effects, and more than 60% was the contribution of abnormal heat[6]. A period of abnormally cold winter in 2015-2016 (December-February) with an increase in the number of days with extremely low temperatures also contributed to overall mortality, increasing it by 8% compared to the average of previous years.
Thus, the impact of climate on humans is diverse and can be both direct and indirect. Indirect impacts are associated with an increase in the frequency of elevated levels of air pollution during abnormal weather conditions. The combination of heat waves and increased air pollution due to unfavourable meteorological conditions can cause additional cases of illness and death.
The direct impact of climate is associated with an increase in climate extremes: an increase in the number of days with adverse weather events (natural disasters), an increase in the number of extremely high and/or low temperatures and the number of sharp temperature variations, and an increase in the number of 0ºC transitions (heatstroke, hypothermia, reduced immunity, increased cold-related diseases, etc.). All these factors increase the risk of mortality from all types of diseases.
The increasing number of scientific publications and monographs assessing the health impacts of global warming[7] and the inclusion of these issues in the Annual Conferences of the International Society for Environmental Epidemiology (ISEE) demonstrate that climate change is becoming an increasingly significant adverse environmental factor with a significant negative and growing impact on human health, increasing risks of death, disease and injury[8].
Another result of climate change is the significant diurnal and seasonal variations in meteorological factors, which places increased demands on the body’s adaptation mechanisms. Depending on the adaptation, the body uses a variety of physiological mechanisms, e.g. increased heart rate, dilation of peripheral blood vessels, increased respiration rate.
Increased meteosensitivity occurs in 20-30% of practically healthy individuals, and in patients with various diseases in 45-90% of observations. Meteosensitivity in urban residents is 1.5-2 times higher than in rural ones, which is associated both with the peculiarities of living in cities and with special bioclimatic conditions formed in urban environment.
Climate change also affects the incidence of naturally occurring focal diseases by altering the conditions of vector populations and the conditions of pathogen development in the vector, with consequent changes in the transmission capacity of many human diseases spread by arthropod vectors (example: Zika fever). Natural disasters have indirect consequences, such as an increase in the number of mosquitoes due to flooding, the activation of ticks and other vectors, and an increase in their potential period of infection.
Adapting populations and urban structures to the impacts of climate change has become a major focus of national governments and metropolitan leadership around the world. The issue became particularly acute following the abnormal heatwave in Europe in 2003, which resulted in thousands of deaths. The year 2010 in the northern hemisphere was the warmest year in 120 years of regular meteorological observations (since 1891), and in the territory of the European part of Russia abnormally hot weather was established.
The Russian Ministry of Health and Social Development sent a letter[9] to the subjects of the Russian Federation with recommendations to develop regional action plans to protect public health from the effects of heat waves, based on a similar document of the World Health Organization[10].
It is obvious that environmental monitoring is one of the key elements of work on informing the population and decision-making of the authorities about potential negative effects of environmental pollution and abnormal climatic factors.
In this case, it is very important that the monitoring allows to determine the exposure both in the foci of pollution, where a small part of the population is exposed to increased concentrations, and the exposure, which affects the majority of the population, ensuring the highest possible spatial resolution and representativeness of the monitoring data.
The regional environmental monitoring system in Moscow includes monitoring of particulate matter PM10 and PM2.5, nitrogen oxides and ozone, which are recognised by the WHO as priority substances for health effects. Moscow was the first constituent entity of the Russian Federation where particulate matter monitoring started on a permanent basis. PM10 suspended solids monitoring has been organised since 2003 in different types of territories and PM2.5 since 2013, with an annual increase in the number of monitoring stations. The number of stations monitoring fine particulate matter PM10 and PM2.5 has increased from seven to 42. Particle monitoring uses internationally recognised reference methods. The only automatic weighing system for PM10 and PM2.5 measurements by the gravimetric reference method in Russia was put into operation. Elemental analysis of dust is also carried out. The total number of automatic stations in Moscow is 59.
Moscow is the first constituent region of the Russian Federation to make data from automatic stations for monitoring atmospheric pollution publicly available online. The creation of the website made it possible to implement the Constitutional right to reliable information on the state of the environment at a modern, high-tech level and to ensure compliance with federal legislation and the provisions of the UN Aarhus Convention in terms of public access to environmental information ahead of the curve.
[1] https://apps.who.int/iris/bitstream/handle/10665/44203/9789244563878_rus.pdf Global health risk factors
[2] https://www.who.int/news/item/22-09-2021-new-who-global-air-quality-guidelines-aim-to-save-millions-of-lives-from-air-pollution New WHO Global Air Quality Guidelines
[3] https://monographs.iarc.who.int/agents-classified-by-the-iarc/
[4] B.A. Revich, Fine particulate matter in atmospheric air and its impact on the health of megacities DOI: 10.21513/0207-2564-2018-3-53-78 UDC 614.72+613.166]:312.2(470-25
[5] D. Shaposhnikov, B.Revich, T. Bellander, etc “Mortality related to interactions between heat wave and wildfire air pollution during the summer of 2010 in Moscow”. Epidemiology. 25(3):359-364, May 2014
[6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3984022/ Mortality Related to Air Pollution with the Moscow Heat Wave and Wildfire of 2010
[7] [Climate change and Human Health...2003, Integration of Public Health with adaptation to climate change..., 2005, Extreme Weather Events and Public Health Responses, 2005 et al.]
[8] https://sk.skolkovo.ru/storage/file_storage/dd58a05b-ca75-4f5b-a58e-5043e97b6e51/SKOLKOVO_EneC_RU_Climate&Health.pdf Assessing health changes in a changing climate and possible adaptation practices
[9] https://rulaws.ru/acts/Pismo-Minzdravsotsrazvitiya-Rossii-ot-18.04.2012-N-14-3_10_2-3936/ Action plan to protect public health from the effects of abnormal heat waves
[10] https://apps.who.int/iris/handle/10665/277069 Action plan to protect public health from the effects of abnormal heat waves: guidelines
Cover photo: EPA
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