Environmental Issues: Making a Difference

Environmental Issues:Making a DifferenceChapter 12

When we look at environmental issues, we become aware that our lives are part of the intricate web of living organisms and nonliving natural resources that make the planet a single, vital ecosystem.

Environmental health has traditionally been concerned with infectious diseases associated with contaminated water, air, food, waste and other pollutants.Water cycleWater and water quality

Surface waterPrecipitation that is stored in lakes, reservoirs and wetlandsGroundwaterPrecipitation that sinks into the groundStored in giant underground reservoirs called aquifersRepresent 95% of the worlds supply of freshwaterWater sources

Water supplies contaminated by industrial and agricultural wastes Found in the wrong place at the wrong time causing conflicts between regions

Problems

Building dams and reservoirs to store surface water

Transfer surface water from one area to another via pipelines and canals

Withdrawing ground water

Converting salt water to freshwater

Adopting water conservation methodsXeriscaping: replacement of green lawns in arid and semi-arid regionsDrip irrigation systemsOrdinances requiring water conservationLow-flow toiletsWater cost raising to reduce useBuilding codes for the use of water-efficient fixtures or appliances. Individual contribution to water conservation. How these problems are solvedDefined as any chemical, biological or physical change in water quality that has harmful impact on living organisms or makes water unsuitable for desired use. Water pollution

FactoriesSewage treatment plantsActive and abandoned minesOil spillsAgricultural feedlotsRunoff from croplands, golf courses, lawns and parking lots

Sources of surface water pollutionStorage lagoonsSeptic tanksLandfillsHazardous waste dumpsUnderground storage tanks filled with gasoline, oil, solvents, and hazardous wasteDumping or spilling of oil, gasoline, paint thinners or other organic solvents onto the ground

Sources of ground water pollution

BiologicalBacteria, viruses and parasitesShort livedMainly cause gastrointestinal problemsChemicalInorganic chemicals (acids, toxic metals, salts)Organic chemicals (cleaning solvents, petroleum products, plastics, pesticides, detergents)Sediment (salt, silt)Radioactive materials ( radon, uranium, isotopes, iodine)Long lasting health problems, including cancer, liver and kidney damage, and birth defectsTypes of water pollutants

Safe drinking water act (SDWA, 1974)Established many health standards for drinking water.Home water treatment devices

Bottled water

It is of special concern the contamination in older homes from lead water pipes and lead solder on pipes. Safe drinking water solutionsEnsuring a sustainable water supply for ourselves and future generations will require several strategies:

Consumers and businesses need to use water saving technologiesFarmers and the agriculture industry need to develop ways to irrigate crops more efficientlyGovernment and policy makers must manage water basins and groundwater fairly and effectively.

Failure to address our water-related problems will lead to economic and health problems, increased environmental degradation and loss of biodiversity.

Who best conserves fresh water?

Read Beating the Oddspg 349

How can you help to conserve water?

ActivityAtmosphere

Air and air quality

Greenhouse gasesOzoneThe presence of one or more chemicals in the atmosphere in sufficient quality and quantity to cause harm to life.

EPA Criteria pollutants Carbon monoxideSulfur dioxideNitrogen dioxideSuspended particulate matterGround level ozoneMetal and metal compounds

Air pollution

EPA Air Quality Index (AQI)

AIRNow - Homepage

Highly reactive gasPoisonous to most living organismsCauses respiratory irritation, aggravates respiratory and heart disease and damages the lungs. Ozone

Particles or droplets of dust, soot, oil, metals or other compounds suspended in the airIf found in the lungs for long time cause irritation and damage to alveoli.Trigger the immune system response, contributing to heart disease and lung disease. Particulate matter

Mixture of pollutants in the lower atmosphere that makes the air hazy

Two types

Industrial smog caused primarily by the burning of large amounts of coal and oil for heating, manufacturing and the production of electric power

Photochemical smog forms when pollutants from motor vehicle exhaust, industry and other sources combine in the presence of sunlight and heat, producing large amounts of ozone and more than 100 other chemicals. SmogSchanghai 1993

Photochemical smog and temperature inversion

The degree of environmental damage from acid deposition depends on the ability of the soil to neutralize acid.Alkaline soils lower damageAcid soils extensive damage. Acid deposit and precipitation

Thinning of the ozone layer of the atmosphere

For the past few hundred years human activities have increased the amount of greenhouse gases in the lower atmosphere

The intensification of the greenhouse effect has led to global warming.

How is it produced?

Global warming

Melting of ice caps and glaciers

Flooding in coastal cities as seas rise

Changed rates of precipitation and evaporation

Storms more frequent and intense

Parts of the world will become drier

Pest and diseases will flourish

Air quality decline (pollution is worse in warm weather).

Predicted effects of global warming

Kyoto protocol (1997)Called for the nations to cut their emmisions of greenhouse gases, particularly CO2, by about 5,2% below 1990 levels by 2012.Allows countries and private companies to trade and sell their greenhouse gas emission allowances to other countries and businessesEncourages private companies to develop new technologies that reduce greenhouse gas emissions.

US emission reduction plan for the nation (2002)Calls for voluntary participation by all sectors of the economy.

Promotion of hybrid gas-electric cars and cars with high fuel economy and low emissions.

Increase of fuel economy standards for new cars and light trucks

Public transportation improvements

What has been done?

Substantial reduction in CO2 emissions will include massive changes in Industrial processesTransportationEnergy sourcesPersonal lifestyles

How can you help improve outdoor air quality?Tune up your carWalk when you canConsider buying hybrid carsTurn down your homes thermostat and water heaterBuy energy efficient appliancesKeep house plants to help clean the air in your home and plant shade trees outside.

Indoor air pollution can be higher and more hazardous than air pollution outside

Most common air pollutants are usually higher inside the home than outsideIndoor air pollution

Solid waste any unwanted or discarded material that is not liquid or gas.

99% produced by mining, oil and natural gas production, agriculture and industrial activities.

Methods for managing solid waste include burning, burying (landfills) and shipping wastes to other states or countries.

Waste management

Any discarded solid or liquid material that meets one or more of four criteriaThe material contains a toxic, carcinogenic or mutagenic compound at levels that exceed EPA safety standards (solvents, pesticides) Catches fire easily (gasoline, oil-based paints)Reactive or unstable enough to explode or release toxic fumes ( chlorine, chlorine bleach)Corrodes metal containers (drain cleaners, industrial cleaners)

Top 5 chemical compounds of concernArsenic, lead, mercury, vinyl chloride, polychlorinated biphenyls (PCBs)

Exposure occurs when wastes leak from sanitary landfills and contaminate water supplies

Effects of these chemicals includeCancer, respiratory diseases, neurological damage, developmental deficits. Hazardous waste

Household hazardous wasteBatteries, paints, cleaners, oils and pesticides

Medical wasteAny solid or liquid waste that is generated in the medical diagnosis, treatment or immunization of human beings or animalsNeedles and syringes, used culture dishes and other glassware, discarded surgical gloves, blood and blood products, tissue samples and any materials contaminated by contact with such products.

Radiation and radioactive wasteLow level radiation products x-rays, nuclear medicine diagnosis and radiation therapyTelevisions, computer monitors, microwave ovens, and cell phones. High level radioactive wasteNuclear weapons and nuclear power plants.

Types of hazardous waste

Landfills, incinerators and hazardous waste repositories are undesirable in a community.

An alternative is to recycle, reduce and reuse resources

Actions to control and prevent waste include:Buying recyclable, reusable or compostable productsComposting yard trimmingsUsing rechargeable batteriesUsing reusable cloth bags for grocery shoppingReducing use of paper towels and other paper productsBuying products with as little Styrofoam, cardboard or paper packaging as possibleStopping junk mailApproaches to waste managementEcosystem an interconnected community of organisms living together in a physical environment as a balanced, mutually supportive system.

Biodiversity variety of different animal and plant species on Earth.

Ecosystems and biodiversity

An ecologically and biologically diverse planet offers innumerable benefits to humans, including:Medicine, food and fuelRecreation, retreat and refreshmentClimate maintenance, water cycling, soil production, waste disposal and pest control.

Human activities have significantly disrupted these ecosystems and caused a decline in biodiversity

Every year, hundreds of plants and animal species become extinct and thousands more are at the risk of extinction.

Deforestation removal of trees from a forested area without adequate replantingAbout 90% of forest loss is occurring in tropical forests. Although tropical forest make up only 6% of the worlds land, they are home to between 50 90% of the terrestrial species.

Effects of human influence on ecosystems

Desertification the conversion of once fruitful land into infertile wasteland or desert.Everyday, an average of 40 square miles of land are turned into deserts by droughts in combination with human activities, such as livestock grazing, poor irrigation techniques and overplanting of crops.

Effects of human influence on ecosystems

Loss of freshwater resourcesNearly half of all freshwater species are now threatened with extinction Many rivers are threatened by industrial, agricultural and city wastes as well as disruption of water flow by dams, channelization and diversion of water for agricultural irrigation.Acid rain and runoffs pollute lakes and deplete oxygen in the waterSome lakes have shrunk or dried up when humans withdrew more water from them than could be replaced by rainfall. Introduction of non-native species disrupts the balance of the ecosystem and usually results in the extinction of native species. Effects of human influence on ecosystems

World population growth

Global carrying capacity the number of people the Earth can support at subsistence levelsSubsistence living includes enough food, water, land and energy to survive

Cultural carrying capacity the number of people the Earth can support at an optimum standard of livingIncludes the luxuries that are part of live in the developed world, such as plentiful food, indoor plumbing, cars and air conditioning.

How many people can the planet support?

The global carrying capacity of Earth is 50 billion peopleThe cultural carrying capacity is much less.

If luxuries are minimized, the cultural carrying capacity could be well above the population of 9 billion projected for 2050. If luxuries are maximized, it is probable lower than the current population of 6 billion

There is probably not enough resources, especially energy resources to extend an optimum standard of living to everyone alive on the planet right now.

If standards of living are to be improved for all the people in the planet population growth has to be slowed by Family planningEmpowering women and increasing their access to educational and employment opportunitiesReducing poverty and infant mortalityImproving access to health careEncourage parents to have fewer, healthier children offering incentives and disincentives to promote smaller families.

Approaches to population controlLooking at environmental issues helps us recognize some of the features that characterize life: interdependence, diversity, adaptability and limits

Acknowledging and honoring these characteristics can help us live in harmony with the environment.

Even though environmental health involves human activities all over the glove, each of us can take actions today to reduce the size of that footprint.