Pollution comes from man made chemicals or natural materials released by human activities. Pollutants are found worldwide in air, water, and land. They disrupt the environment and damage human health.
Major sources of air pollution are:
- Industrial - chemical, refineries, manufacturing
- Power Production - especially coal fired power plants
- Fires - natural and manmade
Following is a table of pollutants, their source and effects:
source: U.S. EPA
Nonpoint source pollution (NPS) is a combination of human-made and natural pollutants that are picked up and spread by precipitation. These pollutants end up in lakes, rivers, wetlands, coastal waters, and underground aquifers. Some NPS pollutants include:
-Excess fertilizers, herbicides, and insecticides from agricultural lands and residential areas
-Oil, grease, and toxic chemicals from urban runoff and energy production
-Sediment from improperly managed construction sites, crop and forest lands, and eroding stream banks
-Salt from irrigation practices
-Acid drainage from abandoned mines
-Bacteria and nutrients from faulty septic systems
From testing 32% of U.S. waters in 2002, the EPA found these to be the greatest surface water pollutants:
- Excess nutrients
- Metals (mostly mercury)
The EPA also reported 45% of stream miles, 47% of lake acres, and 32% of bay and estuary square miles to be unsuitable for fishing and swimming. In one EPA study of 66 mining lands, 75% contaminated surface water with mining wastes. Other known pollution sources included:
-Atmospheric depostion (when precipitation carries pollutants, example: acid rain)
CAFOs, Concentrated Animal Feeding Operations are places where farmers raise many animals such as poultry, swine, or cattle in a relatively small area. Livestock also contributes to 28% of global methane emissions, a greenhouse gas. Animal waste pollutants that run off into water include:
- Erosion sediments
- Pathogens & Bacteria
- Excess nutrients; phosphorous and nitrogen
- Heavy metals
Groundwater comes from precipitation that soaks into the ground and fills spaces between rocks and soil. It provides water for 50% of Americans, 50% of U.S. agriculture, and 30% of U.S. industry. People pollute groundwater above ground with NPS pollutant runoff, as well as underground with septic tank leaks, landfills, mines, and waste in wells.
80% of ocean pollutants come from land. As the amount of contaminant grows, the ocean’s ability to dilute them decreases.
Oceans are polluted by:
-Dredging (excavating and dumping bottom sediments)
Anti-pollution laws for cruise ships are surprisingly weak. Ships can dump untreated sewage once they are three miles off shore. An average cruise ship generates over 900,000 liters of sewage waste per day.
Pollution can become so severe that whole areas of land are abandoned. The U.S. calls these hazardous waste sites superfund sites. The top five worst contaminants on abandoned hazardous waste sites are:
1. Arsenic (mineral element)
2. Lead (metal element)
3. Mercury (metal element)
4. Vinyl chloride (a chemical compound)
5. Polychlorinated biphenyls (PCBs) (a chemical compound)
Many polluted, abandoned lands were once mines. There are 80,000-250,000 abandoned mine lands in the U.S. The pollutants left behind include dozens of minerals and metals. Mining companies pile up waste with limited enclosement or leak prevention. Wastes come in the following forms:
-Slag (left over waste after refinement)
-Sludge (fine mud from drilling)
-Tailings (mining residue)
-Leaching (left over waste after removing ore with water)
Nuclear and mixed waste is another type of hazardous material. Nuclear waste is left over radioactive material from nuclear energy production and medical procedures. A material is radioactive if it emits energy from a harmful substance. Mixed waste is a mix of radioactive and hazardous waste resulting from nuclear weapon and plutonium fuel production. Radioactive materials that must be buried or stored where produced include:
-Nuclear reactor fuel (compounds & heavy metals)
-Uranium mill tailings
Underground Storage Tanks (USTs) are tanks that store hazardous materials like petroleum underground. Tanks will leak if installed, operated, or maintained incorrectly. The result is contaminated water and soil, a fire, or explosion.
Landfills are designated areas for garbage storage. A huge, buried pile of garbage has the potential to release toxic substances into groundwater, and toxic gases into the air.
Agriculture. Farmers use pesticides in large quantities for agriculture. They harm non-targeted species and accumulate in our food. Worldwide pesticide use is about 5 billion pounds a year. Farmers also feed animals hormones for growth, and antibiotics for health in concentrated areas where pathogens travel easily. These additives accumulate in animal tissues and animal products, which we eat. Also, consider the amount of waste produced by cattle and pigs. A pig produces about four times the waste of a human. Often animal waste affects groundwater and rain runoff pollutes streams, lakes and oceans.
Burning forests degrades soil, pollutes the air, increases climate change, and harms plants and animals. Most forest burning is in tropical areas like South America, Africa, and Southeast Asia. Brazil deforested the most area between 1990 and 2005.
forest burning in South America
People clear land by burning forests in order to:
-Build urban areas or roads
See Sustainability and Land Use
Clean up costs
The U.S. emergency hazardous waste clean up program spent $520.7 million in 2007. Of the top ten most polluted places in the world, governments and organizations are spending from $2-40 million for clean up. The Blacksmith Institute, an organization committed to solving pollution problems in developing countries, estimates Chernobyl, Ukraine will need hundreds of billions of dollars for restoration and clean up. (Read Information about these places below).
Health costs are unknown but cases of emphazema and asthma are on the increase worldwide and pollution is suspected for the increase. The World Health Organization (WHO) and the World Bank estimate that a billion people are affected by pollution in poorer countries. One study showed the cost of saving one life in these areas ranges from $42 to $500. In many developing countries there are little if any environmental regulations.
Pollution damage costs
The total economic effect of pollution is unknown. Here are estimates of some effects:
- India loses $5 billion in crops every year from ozone damage.
- Local Minnesota governments are including pollution costs in an economic comparison between a coal plant and an alternative energy facility. They will probably set the cost of carbon at $4 to $30 per ton.
Pollution prevention savings
- A California metal plating company switched to a more efficient process and saved $30,000 annually while reducing pollution discharges from 27-88% percent.
- A Connecticut newspaper saved $50,000 annually by recycling ink, instead of disposing of it as hazardous waste.
- A Kansas auto brake company switched its parts washer from petroleum based to water based, installed an automated powder coater, and eliminated xylene emissions altogether. These three measures reduced oil waste by 73% and saved an annual $66,000.
Acid rain is the combination of moisture in the atmosphere with fossil fuel emissions. This acidic precipitation wears away buildings, damages trees at high elevations, and disrupts the chemical balance of natural waterways.
Ozone depletion occurs when gases like aerosols, CFCs, and HFCs break apart the chemical structure of special oxygen molecules that protect the earth from the sun’s harmful radiation. Fortunately, these culprits (formally mainstays of refrigerants) have been outlawed in developing nations and the ozone layer is repairing itself.
Pollution is the major cause of current climate change. Though the planet has had extreme temperature swings throughout its life, there is liuttle argument that the current state of affairs of rapid climate change is manmade. See Global Warming.
The urbanization of an area creates a surface of concrete and pavement with little trees, resulting in higher temperatures than surrounding rural areas. This is called the Heat Island Effect . Temperatures in urban areas can be up to 10 degrees Fahrenheit higher because they have:
- Fewer trees that provide cooling by shade and evaporation
- Building and cement that traps heat and reduces air flow
- Heat and fossil fuel emissions that add to heat in the air
Poor visibility or haze results when sunlight mixes with air pollutants like dust, particulate matter, smoke, and fuel burning emissions. These pollutants not only reduce our ability to enjoy scenery, but contribute to acid rain and human health problems.
NPS pollution contaminates drinking water, recreation, fisheries, and wildlife. Water becomes overloaded with nutrients and depleted of oxygen, resulting in fish kills. Organic matter runoff produces toxic algal blooms in water. Excess sediment clogs up waterways and damages habitat. Also fatal to aquatic organisms, are chemicals and metals from various sources, and drinking water additives meant to disinfect water supplies. Chloramine, a compound of chlorine and ammonia is one disinfecting additive that not only kills fish and frogs, but causes health problems and breaks down water pipes, leaching toxic lead into water and soil.
When nitrogen, phosphorous, and other nutrients run into oceans, tiny plants called phytoplankton grow, die, and then sink to the bottom. Dead phytoplankton increase bacteria and decrease oxygen in the water. These oxygen depleted areas are called dead zones because marine creatures cannot survive in them. There are about 200 dead zones in the world. Also, millions of animals die each year from entanglement in, or ingesting plastic.
The following pollutants or sources result in toxic substance releases:
- Radioactive soil particles from nuclear waste cause health affects for wildlife as well as humans.
- Landfills may release carbon dioxide and methane into the air and harmful chemicals into groundwater.
- Underground Storage Tanks (USTs) may release petroleum, and fuel additives like MTBE into soil and groundwater.
- Mines contribute to habitat destruction, and land, water, and air contamination. One EPA study of 66 mines across the U.S. revealed 50% contributed to soil contamination, and 25% damaged plants and animals.
- Superfund or hazardous waste sites contain chemicals in the soil, air, water, and plants that are poisonous to humans and animals.
- As farmers continue to apply pesticides, insects become resistant, requiring more and more application. Meanwhile, non-targeted wildlife populations decline, especially endangered aquatic species.
Currently, a great amount of the planet's forests are being destroyed for cattle grazing and agriculture. This has numerous impacts;
- Often the forest are cleared through burning, increasing pollution
- Trees that once absorbed CO2 are now lost.
- Plant and animal extinction
- Soil nutrient depletion
- Flooding and erosion
- Plants’ genetic depletion (affects plants as well as human medicinal values)
How do pollutants affect human health?
Has global pollution gotten worse?
What’s being done about pollution?
What can I do to prevent pollution?
How do pollutants affect human health?
Humans are exposed to pollutants in a variety of direct and indirect ways. Most obviously, people inhale air pollutants and drink pollutants in water. They also ingest them by eating plants that have absorbed pollutants, or by eating meat with pollutants built up in its tissues. People can also absorb some toxins directly into their skin.
Health affects from air pollutants depend on the length and amount of exposure and include damage to human and animal health systems, especially the respiratory system. Air pollutants cause health problems listed on the chart below and are immediate or delayed. In poor countries, people cook over indoor fires, a major air pollution source. Fires release particulate matter and carbon monoxide in smoke at unacceptable levels. The World Health Organization attributes 27% of global disease to indoor air pollution.
Some drinking water contaminants and sources are listed below.
Because land pollutants are picked up and blown in the air, or make their way into water, the health affects are similar to those listed above. One exception is antibiotics and hormones fed to livestock. Animals store these additives in their tissues. When people eat meat or other animal products, they ingest the same additives, and also store them in their tissues. Excess hormones block or mimic our bodies’ natural hormones, and pathogens become resistant to such great amounts of antibiotics.
Has global pollution gotten worse?
Developing countries. Though pollution has decreased in developed countries, it has increased in developing countries. Many governments lack crucial standards or enforcement for pollution control. Pollution from mines, factories, and refineries go unregulated.
In some countries, industrialization is occurring three times faster than the industrialization in the west. Developing countries also use the dirtiest energy sources, such as coal, while residents suffer the health effects. Burning coal provides 2/3 of China’s energy and China has 16 out of 20 of the most polluted cities, according to the World Bank. China and India have been slow to address their pollution problem pointing to the the U.S. and other western industrialized nations that expanded their economies with cheap energy for many years.
The Blacksmith Institute comprised a list of the top ten worst polluted places in the world. They evaluated these places based on the amount and intensity of human exposure to high risk, carcinogenic pollutants. While pollution has decreased overall in developed nations, it has increased dramatically in developing nations as represented in the table below.
In developed nations, the trend has been for reduction of all major air pollutants, primarily due to better efficiency and government regulation. In the United States, all major air pollutants have decreased in the last 25 years. Carbon monoxide has had the greatest reduction.
What’s being done about pollution?
Governments are restoring polluted air, water, and land. Abandoned mine lands are reforested or turned into recreation areas. Large polluters are capturing, compressing, and storing CO2 in a process called carbon sequestration. Polluters and non-polluters are also purchasing and trading emission credits, economic incentives for reducing emissions. (See Buying Green Power)
Developed countries enforce local pollution regulations, such as The Clean Air Act in the U.S. The Act is a federal law that focuses on controlling these specific pollutants:
- Carbon monoxide
- Nitrogen dioxide
- Particulate matter
- Sulfur dioxide.
Governments, non-profits, and local communities are working on pollution apart from regulations. For example, organizations are encouraging shade farming, sustainable harvesting, and protected parks instead of burning forests. International groups like the World Bank and the United Nations Development Program provides resources and knowledge so a country can solve problems, including pollution crises. Governments of developing countries, including some in the top ten most polluted places, are shutting down factories and demanding clean and regulated facilities.
What can I do to prevent pollution?
To reduce water pollution, follow these suggestions:
- Keep litter, pet wastes, leaves, and debris out of street gutters and storm drains
- Dispose of used oil, antifreeze, paints, and other household chemicals properly, not in storm sewers or drains. Do not hose them into the street.
- Have your septic system inspected and pumped, at a minimum, every 3-5 years for proper operation.
- Use permeable paving surfaces such as wood decks, bricks, and concrete lattice to let water soak into the ground.
- Allow thick vegetation or buffer strips to grow along waterways to slow runoff and soak up pollutants.
- Use natural alternatives to chemical fertilizers and pesticides.
- Don't hose down driveways or sidewalks.
- Use low-phosphate or phosphate-free detergents.
- Use water-based household products whenever possible.
- Dispose of excess chemicals at hazardous waste collection centers
To prevent air pollution, follow these suggestions:
- Conserve energy
- Keep car, boat, and other engines properly tuned
- Minimize open burning
- Volunteer for cleaning up a site. Visit Eco-Events to see what's happening in your area.
A simple, five gallon bucket device has helped dozens of communities around the world monitor their air quality. Bucket Brigades is a non-profit environmental program that helps people find the connection between health problems and what they’re breathing. Air pollution data and a simple air testing method have helped communities around the world to reduce pollution, increase safety, and enforce environmental laws.
Oceana, an ocean protection group, introduced Clean Cruise Ship U.S. legislation to reduce boat sewage dumping. The campaign resulted in the second largest cruise line, Royal Caribbean, agreeing to install wastewater treatment on all of its ships.
Since the mid 1980s, ocean oil discharges and spills have dropped by 63 percent and millions of volunteers removed 49 million kilograms of debris from coasts in 127 nations.