Given the great variety of substances present in the atmosphere, numerous classification methods have been proposed: firstly it can be classified according to the chemical composition, for which we mainly speak of compounds that contain sulfur, compounds that contain nitrogen, which contain carbon and halogen compounds.
Secondly, it can be classified according to the physical state: gaseous, liquid or solid; finally, it can be divided according to the degree of reactivity in the atmosphere, into primary or secondary substances. The main effects that pollutants cause in the environment are the greenhouse effect, and acid rain, then of course they also lead to other problems such as the ozone hole and other less visible problems on flora and fauna.
Particulate pollution is responsible for the 1 year reduction in life on average. The pathologies that show a significantly higher risk are those affecting the cardiovascular and respiratory systems, including lung tumors (it should be noted that the relative risk of the latter is still very low compared to tobacco).
It also has an effect on people who engage in physical activity.
The study: Air pollution, physical activity and health: A mapping review of the evidence, published on the Environment international, said us: "Exposure to air pollution and physical inactivity are both significant risk factors for non-communicable diseases (NCDs).
risk factors are also linked so that the change in exposure in one will impact risks and benefits of the other. These links are well captured in the active transport (walking, cycling) health impact models, in which the increases in active transport leading to increased inhaled dose of air pollution.
However, these links are more complex and go beyond the active transport research field. Hence, in this study, we aimed to summarize the empirical evidence on the links between air pollution and physical activity, and their combined effect on individual and population health.
We conducted a non-systematic mapping review of empirical and modeling evidence of the possible links between exposure to air pollution and physical activity published until Autumn 2019. We reviewed empirical evidence for the (i) impact of exposure to air pollution on physical activity behavior, (ii) exposure to air pollution while engaged in physical activity and (iii) the short-term and (iv) long-term health effects of air pollution exposure on people engaged in physical activity.
In addition, we reviewed (v) public health modeling studies that have quantified the combined effect of air pollution and physical activity. These broad research areas were identified through expert discussions, including two public events performed in health-related conferences.
The current literature suggests that air pollution may decrease physical activity levels during high air pollution episodes or may prevent people from engaging in physical activity overall in highly polluted environments.
Several studies have estimated fine particulate matter (PM2.5) exposure in active transport environment in Europe and North-America, but the concentration in other regions, places for physical activity and for other air pollutants are poorly understood.
Observational epidemiological studies provide some evidence for a possible interaction between air pollution and physical activity for acute health outcomes, while results for long-term effects are mixed with several studies suggesting small diminishing health gains from physical activity due to exposure to air pollution for long- term outcomes.
Public health modeling studies have estimated that in most situations benefits of physical activity outweigh the risks of air pollution, at least in the active transport environment. However, overall evidence on all examined links is weak for low- and middle-income countries, for sensitive subpopulations (children, elderly, pregnant women, people with pre-existing conditions), and for indoor air pollution.
Physical activity and air pollution are linked through multiple mechanisms, and these relations could have important implications for public health, especially in locations with high air pollution concentrations. Overall, this review calls for international collaboration between air pollution and physical activity research fields to strengthen the evidence base on the links between both and on how policy options could potentially reduce risks and maximise health benefits. "