Presentation on theme: "Faculty of allied medical science"— Presentation transcript:
1 Faculty of allied medical science Environmental health(NREH-101)
2 Supervision Prof.dr/Mervat Salah Air pollutionSupervisionProf.dr/Mervat Salah
3 Outcomes 1-To know the meaning of air pollution 2-To differentiate between outdoor and indoor pollution3-To know types of air pollution4-To understand the ways to control air pollution
4 AIR POLLUTION Type of Air pollution:- Sources of out door pollution outdoor pollution – indoor pollutionSources of out door pollutionCombustion of fuel (natural gas, petroleum, coal andwood)Industrial processNatural process (Volcanic)
5 Types of Major Air Pollutants Carbon oxides (CO)Nitrogen oxides and nitric acid (NO, HNO3)Sulfur dioxide and sulfuric acid (SO2, H2SO4)Particulates (SPM)Ozone (O3)Volatile organic compounds (VOCs))Types of Major Air Pollutants
6 Pollutants - Secondary pollutants - Primary pollutants Pollutants can be classified as eitherprimary or secondary- Primary pollutantsare substances directly emitted from a process, such as the carbon monoxide gas from a motor vehicle exhaust or sulfur dioxide released from factories.- Secondary pollutantsare not emitted directly. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ground level ozone
8 Environmental challenges Green house effect: Increasing global temperature. Scientists predicting that earth's temperature will increase by 3-40C by year 2030 if the pollution continues to increase at the same pace.Ozone depletion: As ozone layer in the upper atmosphere absorbs incoming harmful ultraviolet radiation but it is now getting thinner & more UVs are reaching in to earth creating different disease like cancer& eye problems.Photochemical smog: In 1952 London was covered by smog for 10 days .This smog was caused by fog, smoke, ash,& SO2 plus NO2.Sunlight played a great role in the formation of this smog .Acid rain: is caused by oxides of nitrogen & sulphur.It increases acidity of soil & effects the growth of trees & plants.
9 Acid Deposition Sulfur dioxides and nitrogen oxides Wet and dry depositionAcid rainRegional air pollutionMidwest coal-burning power plantsPrevailing winds
10 Acid Deposition Wind Transformation to sulfuric acid (H2SO4) and nitric acid (HNO3)Windborne ammonia gasand some soil particles partiallyneutralize acids and form drysulfate and nitrate saltsWet acid deposition(droplets of H2SO4 andHNO3 dissolved in rainand snow)Nitric oxide (NO)Sulfur dioxide(SO2) and NODry acid deposition(sulfur dioxide gasand particles ofsulfate and nitrate salts)Acid fogLakes in shallow soillow in limestonebecome acidicFigure 15.4: Acid deposition, which consists of rain, snow, dust, or gas with a pH lower than 5.6, is commonly called acid rain. Soils and lakes vary in their ability to buffer or remove excess acidity.Question: What are three ways in which your daily activities contribute to acid deposition?See an animation based on this figure at ThomsonNOW.Lakes in deepsoil high in limestoneare bufferedFig. 15-4, p. 351
11 Effects Of Pollution Respiratory diseases in human Toxic metal leachingStructural damageKills fish and other aquatic organismsLeaches plant nutrients from soilAcid clouds and fog at mountaintops
12 Acid Rain + water H2SO4 (Sulphuric Acid) HNO3 (Nitric Acid) Lake Sea Solar RadiationH2SO4 (Sulphuric Acid)HNO3 (Nitric Acid)+waterAcid RainSO2 & NOXFactories, TransportationLakeSeaSEA
14 Effect of Global warming Rise in average global surface temperatureChanges in glaciers, rainfall patterns, hurricanesDroughts and floods. Threat to biodiversityDecreased food productionDiseases (Threats to human health)Economic and social disruptionRising sea levelsExtreme weather
15 Government Roles in Reducing the Threat of Climate Change (1) Regulate carbon dioxide as a pollutantCarbon taxesCap total CO2 emissionsSubsidize energy-efficient technologiesTechnology transfers
17 Unbalanced Green House Effect Naturally Moderated Green House Effect MethaneCarbon DioxideNitrous oxideOzoneCarbon Dioxide50%Methane18%Chlorofluorocarbons14%Ozone12%Nitrous oxide06%EarthEarthThis natural balance may be distorted by Green House Effect as gases such as carbon dioxide have built up in the atmosphere trapping more heatGreen house gases in natural condition insulates the earth against extreme of temperature by limiting both incoming solar radiation & escape of reradiated heat in to space.Contribution of different gases to cause green house effectLess reradiated heat escapes in to spaceSome reradiated heat escapes in to spacesunsunsunMore reradiated heat reflected back to earthInfra-red radiationSome reradiated heat reflected back to earthSurface Temperature increasesSurface Temperature normalAtmosphereAtmosphereUnbalanced Green House EffectNaturally Moderated Green House Effect
19 Ozone Layer thinning Affect on seasonal changes Causes – chlorofluorocarbons (CFCs) that uses in:Coolants in air conditioners and refrigeratorsPropellants in aerosol cansCleaning solutions for electronic partsFumigantsBubbles in plastic packing foam
20 Ozone layer depletion Ultraviolet rays from Sun Chlorofluorocarbons are entering in to atmosphere releasing chlorine. The chlorine than break down the ozoneThe Ozone layer in stratosphere blocks these harmful UV raysOxygenozoneWhole in Ozone layerchlorineThe chlorine released from CFCs break down the ozone molecule.More ultraviolet radiations are reaching in to earths surface as there is a whole in ozone layer.
22 Indoor air qualityIndoor air quality (IAQ) is a term referring to the air quality within and around buildings and structures.IAQ can be affected by microbial contaminants (mold, bacteria), gases (including carbon monoxide, radon, volatile organic compound and particulates) .
24 Major Indoor Air Pollutants Tobacco smokeFormaldehydeRadioactive radon-222 gasVery small particlesSick-building syndrome (SBS)Developing countriesIndoor cooking and heating
25 Air Pollution and the Human Respiratory System Natural protective systemLung cancer, chronic bronchitis, emphysema, asthmaPremature deaths
26 Air Pollutants and its impact on human health Particulate MatterDust and smoke particles cause irritation of the respiratory tract and produce bronchitis, asthma and lung diseases.Dust and smoke function as nuclei for condensation of water vapors and produce smog which attract chemicals like SO2, H2S, NO2,etc. Smog not only reduce visibility but is also harmful due to its contained chemicals.
27 NOISE POLLUTION Sources The term noise is applied to the sound that cause irritation on hearing of healthy human being.SourcesTransport noise--- Originates from road traffic (vehicular), air craft and rail traffic.Industrial noise--- It produced by presses; punch and stamp machine, pneumatic drills, milling machines, cutter and routers, dust extractors. etc.Domestic noise--- It is generated from domestic appliance like washing machines, spin dryers, food mixer, sink waste grinder and vacuum cleaner.
28 Effects Of Noise Pollution Hearing damage from noise exposurePathological and Physiological disordersThe impact of noise may cause permanenthearing loss due to the exposure to noiselevels exceeding 90 dB
29 What is sick building syndrome ? The feeling of illness among majority of occupants of a conditioned space is called “Sick Building Syndrome”.A variety of illness symptoms reported by occupants in sick buildings are – Headache, fatigue, irritation in eyes, nose and throat, shortness of breathe etc.
30 What is sick building syndrome ? Causes:Inadequate ventilation , insufficientsupply of outside air; poor mixing;fluctuations in temperature & humidity;
31 Health Effects of Indoor Air Pollutants Health effects due to indoor air pollutants may be short- as well as long-term.Short-term problemsinclude a stuffy, odorous environment and symptoms such as burning eyes, skin irritation, and headaches.Long-term health problemshave a longer latency period or are chronic in nature.Health conditions involving some allergic reactions, including hypersensitivity pneumonitis, allergic rhinitis, and some types of asthma, are triggered by bioaerosols
32 Control of Indoor Air Pollution Examples include banning smoking in public buildings.Source-isolation strategy is used in situations where a source cannot be completely eliminated. For instance, copy machine areas, food service stations, and bathrooms are often separately vented outside buildings to avoid the recirculation of return air.
33 Questions 1-Sources of out door pollution are………………. 2-Effects Of Noise Pollution are……………3-Two of Effects Of Noise Pollution are…………and………4- Source-isolation strategy is used in situations where a source…………..5- primary pollutants are substances directly emitted from a process, such as the ……………from a or ……..released from ……………..
34 6-What is sick building syndrome 6-What is sick building syndrome ? And it is effect on the health status of human being ?7- What are the environmental challenges?8-What are the classification of pollutants ?
35 Recommended text bookBasic Environmental Health