Cognitive functioning is critical as in our daily life a host of real-world complex decisions in high-stakes markets have to be made. The decision-making process can be vulnerable to environmental stressors. Summarizing the growing economic and epidemiologic evidence linking air pollution, cognition performance and real-world decision-making, we first illustrate key physiological and psychological pathways between air pollution and cognition. We then document the main patterns of air pollution affecting cognitive test performance by type of cognitive tests, gender, window of exposure, age profile, and educational attainment. We further extend to a review of real-world decision-making that has been found to be affected by air pollution and the resulting cognitive impairments. Finally, rich implications on environmental health policies are drawn based on existing evaluations of social costs of air pollution.

Air pollution is one of the most important problems in urban areas that always threaten citizen’s health. Photochemical smog is one of the main factors of air pollution in large cities like Tehran. Usually smog is not only a part of nature, but is being analyzed as an independent matter, which highly affects on the nature. It has been used as relationship between atmospheric elements such as temperature, pressure, relative humidity, wind speed with inversion in the time of smog forming and weather map in 500 Hpa level during 9 years descriptive static by using correlation coefficient in this analyze. Results show that there is a meaningful correlation between atmospheric elements and smog forming. This relation is seen between monthly average of these elements and monthly average of smog forming. However, when temperature decreases, corresponding pressure will increase and result of this will be smog forming. Usually smog increases in cold months of year due to enter cold high pressure air masses in Iran during December and January that is simultaneous with decreasing temperature and air pressure increases and inversion height distance decreases from the earth surface which cause to integrate air pollution under its surface, will cause to form smog in Tehran. It shows a meaningful and strong relation, based on resultant relations by correlation coefficient from inversion height and smog forming, so that obtained figure is more than 60%.

Many countries are facing with the problems of increasing trend of the air pollutant impacts, which are resulted from pollutant dispersing activities in the atmosphere. Photochemical smog also has the most dangerous destroying impacts in the atmosphere.Through this situation the pollutants spread rapidly under the sunlight, and produce a big variety of dangerous chemical complexes, affecting the environment. We have tried to survey the relation of variables for smog formation in the city through the “Pearson” formula to calculate the integration coefficient.Deductive statistical methods like integration coefficient and linear equilibrium of regression, to were used find the logic relation of the variables like air pollutants, and inversion. Air maps in the contour line of 250, 500 hpa and the statistical duration of (1998-2007) were studied monthly in smoggy days.As a result' the relationship between these pollutants and the process of the smog formation was estimated to be more than 90%, and it increases according to the cold air flows, inversion, and it‘s low height from the earth surface.

This work investigated the connection between O3 and other pollutants and meteorological conditions during a smog episode in Delhi. Ozone concentrations varied from site to site (150~269µg/m3). A significant negative correlation has been observed between O3 and its precursor gases. Wind speed showed a positive correlation, but high wind usually dilutes the pollutant concentrations. Thus, a positive correlation with wind speed represents ozone transport from other locations to observational sites. The high ratio of PM2.5 to PM10 indicates a predominance of human involvement. Toluene and benzene ratios(T/B) are estimated to understand the nature of emission sources and the lifetime of pollution. The analysis of the benzene and toluene fractions indicates anthropogenic air masses' dominance. Very high T/B values at several sites indicated that benzene was emitted from vehicular emission while toluene was from point sources. Ozone formation potential analysis showed that toluene and p-xylene are the prime contributors to ozone.

Simple models of photochemical air quality are necessary to represent raw guesses for photochemical smog amount. Semiempirical models have constant parameters which must be determined by using of the mathematical methods and local experimental concentrations of pollutants. These parameters are determined for Mashhad in this paper. The results of three models are compared with the existing experimental data. With respect to this comparison, it can be concluded that the model containing temperature parameter is the best model because the number of its average bias and standard deviation is fewer than it of the other models, and also it predicts better the peak of ozone concentration arisen in midday.    

The concentration of ground-level ozone is the result of thousands of complex chemical reactions. Basically, an increase of ozone concentration occurs in the presence of NOx, VOCs, and the sun’ s radiation. This study deals with analyzing the ground-level ozone in Isfahan city from November 22 to December 21 (a full solar month) in 2009. According to the observations made by the Isfahan Meteorological Organization, photochemical smog was visible over the city during this month. The data used in this study include NO2, NO and O3 concentrations and the meteorological variables of temperature, relative humidity and wind speed which have been measured in Isfahan in 2009. The analyses were carried out for the sunshine hours in two time periods of 9 to 12 am and 6 am to 15 pm whose main characteristics are: A) During 6– 15 period: the sun rises from 6 am and by becoming closer to the dusk, i. e. about 15 pm, both the radiation intensity, and temperature decrease; B) During 9– 12 period: the higher temperature, radiation intensity, and traffic are the effective factors in the emission of pollutants when compared to the other hours of the day. The days under study are classified based on maximum, minimum and average ozone concentration. In order to analyze the tropospheric ozone and smog creation, in this study, the photochemical and semi-empirical models were used. The kinetic and mechanism of a number of photochemical reactions effective in ozone formation were taken into account in order to analyze the changes in ozone concentration. Calculations were carried out by using the Excel and Matlab software programs. Making use of the steady-state approximation method and considering oxygen atom in the steady state, the reaction rates have been computed. The differential relation obtained (d[O3]/dt = k2k1[NO2]-k3[O3][NO]) is a function of three variables of NO, NO2 and O3 concentrations. The amounts of reaction rate (d[O3]/dt) and also the rate constants k2k1 and k3 were also calculated. Analysis of the experimental relation between the activation energy and the results obtained from calculations indicate that the reactions that take place in the troposphere can be considered rank 3 reactions. In the troposphere, the quantum of energy (hν ), which is released in some reactions, is very strong. The activation energies obtained for all days of this study include negative values, and this confirms the fact that the energy of the photons of the sun is needed to change NO2 and O2 to O3 in the troposphere. Based on the negative activation energies obtained, we can consider the reaction NO2+O2+ hν → NO+O3 as the mechanism for the tropospheric ozone production in Isfahan. The creation of photochemical smog, SP(t) with t denoting the time, during the mentioned days was studied based on the Jonson’ s semi-empirical model. The relations obtained based on the changes in NO and O3 concentrations with respect to time show that smog creation follows a quadratic nonlinear relation. In general, the increase of the concentration of pollutants on the ground as a result of photolysis reactions has led to the production of ozone concentrations. The results achieved from the analysis of reaction rate, smog creation, and the resulting curves indicate that ozone concentration has not been uniformly increasing or decreasing during the studied days, but there were both the increasing and decreasing trends. In general, the photochemical reactions taken place in the atmosphere of Isfahan city have caused both production and loss of ozone. Consequently, the investigation showed that the changes of the ozone concentrations under the effects of the solar radiation followed the same pattern in autumn 2009. On the other hand, the changes in the ozone concentration on the ground level caused changes in smog creation during the studied time. With regard to the above-mentioned arguments and on the basis of the effect of nearly the same conditions, a constant process prevailed. It could be predicted that this pattern will be the same in the future years.