Air pollution Flashcards
Historically what has caused air pollution?
historically air pollution has been the result of smoke and high levels of sulphur dioxide being released from the combustion of sulphur rich fossil fuels such as coal
What pollutants do traffic emissions release?
Traffic emissions release Carbon monoxide, NOx, VOCs and Particulates
How are vehicle emissions leading to the formation of ozone (O3)?
VOC’s undergo sunlight induced oxidation, a photochemical reaction, in the atmosphere in the presence of NO2
Which vehicle emission compound leads to acid rain?
NOx
What are primary pollutants?
These are pollutants that form directly at the source and enter the environment in that form e.g smoke SO2
What are secondary pollutants?
Pollutants formed within the system as a result of 2 compounds reacting e.g NOx, ozone
What are the 2 ways that air quality is measured?
- continuous automatic monitoring, provides the concentration of pollutants at any given time, real time information
- non continuous monitoring, provides average concentrations for a given time period, e.g days, weeks, months etc.
What is Black smoke?
Black smoke is smoke rich in particulates formed primarily from traffic emissions. Black smoke is measured by the blackening effect on filters. Particulates within black smoke may be dangerous due to the pollutants that adsorb onto their surface
What makes up particulates?
Particulates may be formed from combustion sources (primarily traffic emissions), secondary particles (Sulfate and nitrate formed in the atmosphere) and coarse particles such as soil/dust, salt, biological and construction site particles.
what is the danger of fine particles?
Can be carried into the lungs causing inflammation of the respiratory system which further enhances the effects of respiratory and heart diseases.
carcinogenic pollutants may also be adsorbed onto the surface of particles.
what is the sulphur content of fuels?
Coal - 7% Heating oils - 4% Coke - 2.5% Diesel - 0.9% Petrol - <0.1% Gas
What are the sources of SO2?
natural sources - volcanoes
Primarily from the burning of fossil fuels - coals and heavy oils.
What are the health effects of SO2?
Fall in lung function for asthmatics and at higher concentrations causes tightness of the chest for asthmatics possibly leading to medical attention
what are the sources of NOx?
motor spirits, diesel, coal - traffic emissions and electrical industry
How is NO2 harmful to the health ?
NO is not harmful however when oxidised to NO2 it is.
NO2 may irritate the lungs leading to an increased susceptibility to influenza, long term exposure to high levels may lead to acute respiratory illness in children, it also contributes to ozone formation.
