Air Pollution SoucresAir Pollution Soucres

NaturalNatural

ParticulatesParticulates

Pollen, smoke, dust/ash from volcanoes,fungus spores,Pollen, smoke, dust/ash from volcanoes,fungus spores,salt praysalt pray

GasesGases

Carbon monoxide, terpenes from pine trees, Carbon monoxide, terpenes from pine trees, hydrogen sulfide and methane decomposition hydrogen sulfide and methane decomposition

Air Pollution SourcesAir Pollution Sources

Man-madeMan-made

Stationary combustionStationary combustion

TransportationTransportation

Industrial processesIndustrial processes

Solid waste disposalSolid waste disposal

Human Health and Air PollutionHuman Health and Air Pollution

ThresholdThreshold

There are several possible relationships between pollutant dose There are several possible relationships between pollutant dose (the amount to which you are exposed) and human response (an (the amount to which you are exposed) and human response (an effect caused by the pollutant).effect caused by the pollutant).

Some pollutants have no effect at low doses, but very severe Some pollutants have no effect at low doses, but very severe effects at high doses. In other words, there is a threshold effects at high doses. In other words, there is a threshold below which the pollutant has no adverse effect.. below which the pollutant has no adverse effect..

Other pollutants seem to produce an effect at any level.Other pollutants seem to produce an effect at any level.

Scientists have not been able to quantify the relationship Scientists have not been able to quantify the relationship between most pollutants and the effect they cause.between most pollutants and the effect they cause.

Total Body BurdenTotal Body Burden

Not all of the pollutant a person is exposed to comes from the air. Not all of the pollutant a person is exposed to comes from the air. For example a person may breathe in about 50 micrograms of For example a person may breathe in about 50 micrograms of lead per day while their intake from food and water could be 300 lead per day while their intake from food and water could be 300 micrograms per day.micrograms per day.

Most pollutants require time to react and cause an effect. The time of Most pollutants require time to react and cause an effect. The time of exposure is as important as the amount of the pollutant.exposure is as important as the amount of the pollutant.

Time vs DosageTime vs Dosage

ExampleExample

CO combines with hemogloben CO combines with hemogloben to form carboxyhemoglobin. to form carboxyhemoglobin. When your blood has 60% When your blood has 60% carboxyhemoglobin you die carboxyhemoglobin you die from lack of oxygen.from lack of oxygen.

SynergismSynergism

The effect is greater than the sum of the parts.The effect is greater than the sum of the parts.

For example, black lung in coal miners occurs mostly when the For example, black lung in coal miners occurs mostly when the miner also smokes. Coal mining alone, or smoking alone will miner also smokes. Coal mining alone, or smoking alone will usually not cause black lung.usually not cause black lung.

Respiratory SystemRespiratory System

When pollutants are taken into the When pollutants are taken into the body they may be adsorbed into the body they may be adsorbed into the bloodstream or moved out of the bloodstream or moved out of the lungs by small hair cells called cilia lungs by small hair cells called cilia that are constantly sweeping mucus that are constantly sweeping mucus up into the throat.up into the throat.

Particles larger than 0.1 microns Particles larger than 0.1 microns are usually caught in the upper are usually caught in the upper respiratory system and swept out respiratory system and swept out by the cilia.by the cilia.

Particles smaller than 0.1 microns Particles smaller than 0.1 microns can move into the alveoli where can move into the alveoli where there are no cilia and they are there are no cilia and they are trapped, causing damage to the trapped, causing damage to the lung tissue.lung tissue.

Acid RainAcid Rain

SOSO22 + O + O SO SO33

SOSO33 + H + H22O O H H22SOSO44

NO + ONO + O33 NO NO22 + O + O22

NONO22 + O + O33 + H + H22O O 2 HNO 2 HNO33 + O + O22

Photochemical SmogPhotochemical Smog