Pollution

Pollution defined asSomething that is unwanted that interferes with the environment and an organisms self sustaining processes in a negative way- The textsA change in the physical chemical and biological characteristics of air water and food that adversely effects the survival of organisms.

Basic Toxicology

Basic ToxicologyToxin=Damages a living organism by ingesting or absorbed.Toxicity=the degree which a toxin harmful. Any thing in high enough quantities may be harmfulEx water

Factors to considerDosage Amount of exposure Size and age or organismAbility of organism to detoxifySensitivity to substanceSynergistic/Antagistic effects

Dose response analysis 2 tests LD 50 when 50% die Poisons-LD50= 50 mg or lessThreshold dose=when a negative effect occurs

Types of effects Acute-Short exposure to a high level of toxinEx snake biteChronic-Long term exposure to a low level toxin.

Risk assessment/management Assessment calculations of the risk takenManagement=strategies taken to reduce risk

Air Pollution

Air Pollution 2 sources human and naturalNatural=volcanoCar=man The majority of the pollution today is from man and occurred after the industrial revolution.

Beijing is one of the most polluted cities

SourcesPrimary pollutants released directly into the lower atmosphere and are toxic.Ex mercury coal burning Secondary-toxins formed in the atmosphere from multiple primary pollutants.SO2 from coal +H2O H2SO4

EPAEnvironmental Protection AgencyRegulates pollutionRegulates 6 Criteria PollutantsCarbon monoxide CO-combustion-60% carLead Pb-from coal and smeltingOzone O3-good in stratosphere-bad in troposphere-from combustion.Nitrogen Dioxide NO2-car engines forms nitric acid Sulfur dioxide SO2 coal and dieselsulfuric acid Particulates

ChangesSince 1970 CO and lead have decreasedNew concerns=VOC volatile organic compounds.Toxic organic compounds from manufacturing, dry cleaning, industrial solvents, form O3

SmogFog=natural water vaper2 types industrial and photochemicalSmog=Toxic gas

Industrial Smog

Industrial (grey) smog- formed from the burning of coal common 1900-1950.CO2 combines with particulate matter. Problems=Sulfuric acid lead particulate matter.Lead to- pneumonia, tuberculosis,heart failure, bronchitis, whooping cough. 1952 killed 4000 in London

Photochemical smog

Photochemical Smog.The brown cloud found on sunny days. Caused by car combustion and industrial combustion.VOC, NOx, O3 combine, catalyzed by sunlight, to form a toxic gas. Common in baltimore

InversionAir is trapped by warmer layers of air in low places.

Climate change

Caused By Increasing CO2 and other green house gasses cause the green house effect.1900-1950 25% caused by combustion 75% by reducing biomass.1950-today 75% by combustion 25% by reduction in biomass.

IPCC (Intergovernmental panel on climate change) report 1-Climate change is occurring There is a correlation between temperature and CO2 levels (greater than 90%)CO2 1950 280ppm 2006 380ppmMethane 1950 715ppm 2005 1774ppmNOx 270-319

Rise in CO2

EffectsAdditive effect decrease in ice caps= increased temperatures.Increased heat = increased H2O gas=increased heat.Increased temp=less permafrost=more Co2 released from the permafrost.Increased temp= decreased land= less biota and more CO2

ImpactHigher levels of water-maryland 4th most at riskDecreasing glaciers=less drinking waterIncreased storms

Ozone depletion

Ozone depletion Ozone in stratosphere is a toxin but in the stratosphere provides a defense from UV radiation. Formation 3O2 + UV sunlight 2O3

Ozone depletionOccurs during the summer months. Caused by Chloroflurocarbons (CFCs) And other compoundcompounds used in propellants, fire extinguishers, and hair spray.

Reaction CFCs break down to Chlorine gas and reacts with ozone Cl + O3 O2+ClOis stored in ice crystals over the winter.In the spring the crystals melt and continue to reactClO+O Cl+O2

Results26 million square Km zone of thinness (hole).Chronic Exposure= eye cataracts, skin cancer, weakening of immune system.Kill phytoplankton,-primary producers.

Acid rain

Acid rain:Formed from SO2 and NOx and water into sulfuric and nitric acidspH=range from 5.4-2.3Caused by coal and auto emmissions

Environmental effectsMineral leachingSulfur and nitrogen buildup in soil/lakesIncreased aluminum buildupLeaching of calcium from conifersLowering of pH in lakesHuman respiratory irritationDissolving stone-monuments buildings exc.

2 types Dry acidic particle deposition-drops few days afterWet deposition-drops 4-14 days1990 Clean air Act reduced SO2 and NOx levels.