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Unit 6 Health, Risk, ToxicologyRisks & HazardsCh.15Risk is a measure of the likelihood that you will suffer harm from a hazard.

We can suffer from:Biological hazards: from more than 1,400 pathogens.Chemical hazards: in air, water, soil, and food.Physical hazards: fire, earthquake, volcanic eruptionCultural hazards: smoking, poor diet, unsafe sex, drugs, unsafe working conditions, and poverty.

7 deadliest infections kill 13.6 million people worldwide every year

Global HIV/AIDS Epidemic:AIDS has reduced the life expectancy of sub-Saharan Africa from 62 to 47 years 40 years in the seven countries most severely affected by AIDS.Projected age structure of Botswana's population in 2020.Figure 18-21Unit 6 Health, Risk, ToxicologyChemical Hazards & PollutantsCh.15Point SourceNon-Point Source (Area Source)Mobile Source

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Unit 6 Health, Risk, ToxicologyCh.15Toxic Heavy Metals: MercuryLead Cadmium Nickel Gold Platinum Silver Bismuth Arsenic Selenium* Vanadium Chromium Thallium*Not classified as a metalFigure 18-2Interactive Periodic TableEach are:Found in nature Used in industryBy-products mining for other elementsMetals tend to be stored in fatty tissue (sometimes permanently) creating a body burden (content of heavy metals in our bodies)

We all live with metals stored in our tissues

3Unit 6 Health, Risk, ToxicologyToxic Pathway &BiomagnificationCh.15Figure 18-2

4Unit 6 Health, Risk, ToxicologyCh.15Volatile Organic Compounds: (VOCs)Carbon compounds that evaporate easily at room temperature.

Found in many household and industrial items: paints, paint strippers, and other solvents; wood preservatives; aerosol sprays; cleansers and disinfectants; moth repellents and air fresheners; stored fuels and automotive products; hobby supplies; dry-cleaned clothing.

Usually VOC levels are 2 -5% greater indoors than outdoorsFigure 18-2Short-Term (Acute) effectsEye, nose and throat irritationHeadachesNausea / VomitingDizzinessWorsening of asthma symptoms Long-Term (Chronic) effectsIncreased risk of:CancerLiver damageKidney damageCentral Nervous System damage Organic Compounds:Carbon compoundsSynthetic Organic Compounds:100,00 chemicals have been commercially available. Wide range of adverse environmental effectsPersistent Organic Pollutants (POP):Often contains volatile chlorineResistant to environmental degradationCan be transported long distances by wind, water and sediments

Many POPs are currently or were in the past used as pesticides. Others are used in industrial processes and in the production of a range of goods such as solvents, polyvinyl chloride, and pharmaceuticals.5Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2Hormonally Active Agent (HAA)A type of POP that effects the endocrine system

Pituitary hormone affecting growth & development of all glands - GH oxytocin/prolactin milk producing/uterine contraction

Pineal melatonin controls wake/sleep cycles (reduces when you get older)

Thyroid Thyroxin (iodine containing) Goiter - when iodine deficient in an attempt to make more hormone the thyroid increases in size Growth & Development

Thalmus Thymosin immune regulator

6Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2Radiation Thermal Pollution

7Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2Thermal PollutionDirections Examine the data in the table below. It shows the concentration of dissolved oxygen available in water at different temperatures. The oxygen available to fish is in units marked ppm or "parts per million."Water Temperature (Degrees Celsius)Concentration of Dissolved Oxygen(ppm)307.8209.01010.5014.1Construct a line graph of the data on the left.

A certain species of fish normally live in a pond that never exceeds the temperature of 10 degrees Celsius. this species of fish requires a dissolved oxygen level 9.5 ppm. Industrial development has the potential of increasing the pond's temperature by releasing hot water produced during necessary process. Answer the questions below based on your knowledge of biology and using your graph. (a) According to your graph, at what temperature would the dissolved oxygen level in the pond drop below the required level? (b) What impact would the change in temperature have on the fish. Explain your reasoning in complete sentences.

Using complete sentences, suggest two (2) ways of preventing the thermal pollution and still have the industrial development occur.

8Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2Thermal PollutionConstruct a line graph of the data on the left.

A certain species of fish normally live in a pond that never exceeds the temperature of 10 degrees Celsius. this species of fish requires a dissolved oxygen level 9.5 ppm. Industrial development has the potential of increasing the pond's temperature by releasing hot water produced during necessary process. Answer the questions below based on your knowledge of biology and using your graph. (a) According to your graph, at what temperature would the dissolved oxygen level in the pond drop below the required level? (b) What impact would the change in temperature have on the fish. Explain your reasoning in complete sentences.

Using complete sentences, suggest two (2) ways of preventing the thermal pollution and still have the industrial development occur.

a)17 OC

b)temperature change reduces the dissolved oxygen level and produces respiratory stress in the fish population.

3) - Hot water could be stored in holding ponds before release.- Hot water could be used in some part of the factory.- Cooling towers could be constructed to let heat leave the water before it is released.

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Electromagnetic Fields (EMF)

Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2RadiationThermal PollutionParticulatesAsbestosNoise PollutionCultural

Smoking Epidemic Stages

Dust, soot asbestos fibers released into the airFrom: dust storms, volcanic eruption, combustion10

Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2

11Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2

Dose response curve. Low concentrations may be harmful to life. As the concentration increases, it may be beneficial to life.12

Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2Dose response curves. LD-50:Lethal Dose The dose at which 50% of the population diesED-50:Effective Dose The dose that causes an effect in 50% of the populationTD-50:Toxic Dose The dose that is toxic to 50% of the population13Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2

14Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2

15Unit 6 Health, Risk, ToxicologyCh.15Figure 18-2

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Unit 6 Health, Risk, ToxicologyCh.16Figure 18-2Natural Hazards: Potential for property damage & a threat to human well beingNatural Disasters: Significant loss of life & property over a short time & in a specific locationCatastrophe: Massive disaster requiring significant time and money for recovery17Unit 6 Health, Risk, ToxicologyCh.16Figure 18-2Natural Hazards Fundamentals: Natural Hazardsprovide service functions are predictable can be linked to other hazards severity is linked to the biological and physical environment are creating more damage and loss of life than in the past risk can be estimated negative effects can be minimized

18Unit 6 Health, Risk, ToxicologyCh.16

Figure 18-2Natural Hazards Fundamentals: Natural Hazardsprovide service functions are predictable can be linked to other hazards severity is linked to the biological and physical environment are creating more damage and loss of life than in the past risk can be estimated negative effects can be minimized

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Unit 6 Health, Risk, ToxicologyCh.16Figure 18-2 are predictable

20Unit 6 Health, Risk, ToxicologyCh.16Figure 18-2 can be linked to other hazards severity is linked to the biological and physical environment

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Unit 6 Health, Risk, ToxicologyCh.16Figure 18-2 are creating more damage and loss of life than in the pastDue to:Poor land-use planning & exponential human population growth22Unit 6 Health, Risk, ToxicologyCh.30Figure 18-2Solid Waste Management:EQs (ch.30):What are the advantages and disadvantages of: Recycling? Composting? Onsite disposal? Incineration? Open dumps? How do the physical and hydrologic conditions at a site effect its suitability as a sanitary landfill?What are the multiple barriers used in landfills and how are they monitored?Why is the disposal of hazardous chemicals one of our most pressing environmental issues?How are chemical wastes managed?What problems are related to ocean dumping and why are they likely to persist for some time?23Unit 6 Health, Risk, ToxicologyCh.30Figure 18-2Integrated Waste Management: current dominant concept of waste management meant to manage municipal (MSW) and industrial solid wastes we produce and reduce or prevent their production. R-R-RReduce, Reuse, RecycleCan reduce solid waste making it to a landfill by 50%CompostingUsing organic waste as fertilizerSanitry LandfillConcentrating, and covering solid waste in a confined areaIncinerationBurning combustible waste at high temperaturesIncludes:

Reuse and recycling are hindered by prices of goods that do not reflect their harmful environmental impacts, too few government subsidies and tax breaks, and price fluctuations.

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Unit 6 Health, Risk, ToxicologyCh.30Figure 18-2CompostingUsing organic waste as fertilizer

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Unit 6 Health, Risk, ToxicologyCh.30Figure 18-2Incineration:Waste to Energy

Releases:Dioxins (a POP)Heavy MetalsParticulatesInorganic Acidic Gases (HCl, SOx, NOx)ButVastly reduces waste volume (75%-95%) and creates energy In a wet scrubber, the polluted gas stream is brought into contact with the scrubbing liquid, by spraying it with the liquid, by forcing it through a pool of liquid, or by some other contact method, so as to remove the pollutants. Wet scrubbers can remove both gases and particulate matter

An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream

26Unit 6 Health, Risk, ToxicologyCh.30Figure 18-2Landfills

Open dumps: are fields or holes in the ground where garbage is deposited and sometimes covered with soil. Mostly used in developing countries.Sanitary landfills: solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam.

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Unit 6 Health, Risk, ToxicologyCh.30Figure 18-2Landfills

GeomembraneSanitary landfills: solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam.28

Unit 6 Health, Risk, ToxicologyCh.30Figure 18-28 Ways pollutants from sanitary landfill may enter the environmentNoxious liquid that percolates from the surface or through the waste via groundwater movementMethane, ammonia, hydrogen sulfide and NOXHeavy Metalshttp://www.dust-control-inc.com/Landfill-Closure.htm landfill info29Figure 18-2

No open burningTrade-OffsEventually leaks and can contaminate groundwaterDiscourages recycling, reuse, and waste reductionSlow decompositionof wastesGroundwater contaminationReleases greenhouse gases (methane and CO2)unless they are collectedAir pollution from toxic gases and volatile organiccompoundsDustNoise and trafficNo shortage of landfill space in many areasFilled land can be used for other purposesCan handle large amounts of wasteCan be built quicklyLow operating costsLow groundwaterpollution if sited properlyLittle odor

Sanitary LandfillsAdvantagesDisadvantagesDustNoise and traffic30Figure 18-2Unit 6 Health, Risk, ToxicologyCh.30Hazardous Materials: material that is toxic, ignitable, corrosive, or reactive enough to explode or release toxic fumes.The two largest classes of hazardous wastes are organic compounds (e.g. pesticides, PCBs, dioxins) and toxic heavy metals (e.g. lead, mercury, arsenic).

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Figure 18-2Unit 6 Health, Risk, ToxicologyCh.30Hazardous Waste Legislation:

Two major federal laws regulate the management and disposal of hazardous waste in the U.S.:Resource Conservation and Recovery Act (RCRA)Cradle-to-the-grave system to keep track waste.Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)Commonly known as Superfund program.The Superfund law was designed to have polluters pay for cleaning up abandoned hazardous waste sites.Only 70% of the cleanup costs have come from the polluters, the rest comes from a trust fund financed until 1995 by taxes on chemical raw materials and oil.

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Figure 18-2Unit 6 Health, Risk, ToxicologyCh.30Hazardous Waste Storage: Deep-well disposal: liquid hazardous wastes are pumped into dry porous rock far beneath aquifers.Surface impoundments: ponds, pits, or lagoons into which liners are placed and liquid hazardous wastes are stored.Long-Term Retrievable Storage: Some highly toxic materials cannot be detoxified or destroyed. Metal drums are used to stored them in areas that can be inspected and retrieved.Secure Landfills: Sometimes hazardous waste are put into drums and buried in carefully designed and monitored sites.

33Figure 18-2Unit 6 Health, Risk, ToxicologyCh.30Ocean Dumping:

Marine debris on the coast of Hawaii

34Figure 18-2Unit 6 Health, Risk, ToxicologyCh.30There is no away** Add disposable society information and external costs of production35