(2) Pollution

Air Pollution Causes More than 6 Million Deaths Worldwide

air-pollution

Less forgiving than our planet

A facility known as Biosphere 2 was designed to test a supposition often made by economists - which technology can substitute for natural life support systems. Biosphere 2 was to model a spacecraft that could allow humans to travel in space indefinitely. Within the structure, everything was to be sustainable. Built in the State of Arizona at a cost of $200 million, the 3.2 acres (1.3 hectares) of Biosphere 2 are a closed-off mini-Earth containing tiny biomes – a marsh from the Florida Everglades, an equatorial rain forest, a coastal desert, a savanna with a stream and grasses from three continents, an artificial mini-ocean with a coral reef, plus an orchard and intensive agricultural area. Its underbelly holds a maze of plumbing, generators, and tanks. In 1991, eight people started living in Biosphere 2 to test its ability to support life. They lived within the facility for two years. The first year went well, but in the second, crops failed, and people grew thin. They became dizzy as atmospheric oxygen levels fell from 21% to 14% – a level typical of a 14 000 feet (4270 m) elevation. This occurred because excessive organic matter in the soil absorbed oxygen from the air as did the type of concrete used. Atmospheric carbon dioxide “spiked erratically,” while nitrous oxide rose to levels hazardous to brain function. Vines and algal mats overgrew other vegetation. Water became polluted.

The Biosphere initially had 3800 plant and animal species. Among the 25 introduced vertebrate species 19 died out over the two years, and only a few birds survived. All the Biosphere’s pollinators – essential to sustainable plant communities – became extinct. Excitable “crazy” ants destroyed most other insects.

▪In 1997, Columbia University took over Biosphere 2 for use as an educational facility designed to teach Earth stewardship, a place to “build planetary managers of the future.” Its research efforts included studying the effects of various levels of the greenhouse gas carbon dioxide on plant communities. That effort ended and the University of Arizona is now in charge.

▪ Someone noted that Biosphere 2 is less forgiving than our planet.

But Earth is a closed system too. History records many examples of civilizations that failed or grew weak after severely impacting their local environments. But survivors often moved on to other environments. Today, many people still struggle to “move on,” but there are fewer and fewer fresh locales into which Earth’s huge population can move.

The technical problems of Biosphere 2 could probably be solved. But for the whole Earth, or major parts of it, can we substitute technology for nature’s services, for breathable air, or for fertile clean soil?

What is happening to Earth’s ecosystems?

Keeping in mind our absolute dependence on Earth’s ecosystems and the major stresses on them, how well are they still providing their natural goods and services? The first systematic examination of this question was a four-year $20 million study, the Millennium Ecosystem Assessment (MEA). Carried out by 1400 scientists worldwide under the aegis of the UN Environment Program’s (UNEP), the MEA evaluated the health of the planet’s forests,

coastlines, inland waters, shrub lands, dry lands, deserts, agricultural lands, and other ecosystems vital to human and natural welfare. Helping investigators to envision what was happening were 16 000 photographs donated by the US National Aeronautics and Space Administration (NASA). Taken from space by satellite, these showed changes occurring in the 1990s in biomes such as coastlines, mountains, and agricultural land.

In 2005 MEA provided some answers as to what is happening to ecosystem services. Their report revealed that at least 60% of services supporting life on Earth including fresh water, fisheries, and many other services are being used unsustainably. The report, Living Beyond Our Means: Natural Assets and HumanWell-being,13 has shown that we are using about 1.25 Earths’ worth of resources, even while human population and consumption continues to increase. Consequences of environmental degradation could become more obvious in coming years. Although results were extremely worrisome, the study pointed toward means by which we can improve ecosystem management.

See http://millenniumassessment.org/en/index.aspx, home page of the MEA, which links to the reports summary and other reports including Living Beyond Our Means. Also see the World Resources Institutes EarthTrends at http://earthtrends.wri.org/ for more useful information on Earths ecosystems.

When pollution is obvious

If you read that a pollutant is “any substance introduced into the environment that adversely affects the usefulness of a resource” you may yawn. But pollution literally hits you if you live in a city where emissions from cars, trucks, and motorbikes sting your eyes, congest your nose, cause your head to ache, or tighten your breathing.

▪ In the 1960s and ’70s, pollution in the United States, a wealthy country, was often blatant. Some rivers were obviously polluted by industries operating on their banks. Oil floating on the surface of Ohio’s Cuyahoga River caught on fire more than once. One fire in 1959 burned for 8 days.

▪ Air pollution was obvious too. In industrial cities soot drifted onto streets and clothing, and into homes. Severe air pollution episodes increased hospital admissions killing sensitive people. Trash burned in open dumps.

▪ Heavy pesticide use killed fish, birds, and other animals.

▪ The new century finds the environment in industrialized countries improved. But continuing population growth in the United States and unremitting, indeed accelerated, land development may be reversing some of that progress. And the United States, once an environmental leader, abandoned that role in the first decade of the twenty-first century.

Just as a weed is “a plant out of place,” a pollutant is “a chemical out of place.” Oil enclosed within a tanker is not a pollutant. Spilled into the environment, it is. However, doing harm often involves more than being out of place. A small oil spill may go unnoticed, but a large one can be disastrous. Circumstances are important too. If the oil is of a type easily degraded, or one that evaporates easily, or if wind blows the spill quickly away from a shoreline, there may be little harm. But, coming ashore, oil may devastate animals, birds, and other shore-dwelling organisms.

Almost any substance, synthetic or natural, can pollute. However, it is synthetic and other industrial chemicals that are emphasized here. If we learn that industrial chemicals in a water body are obviously impairing the ability of birds to reproduce, or are associated with fish tumors we all agree that the water is polluted. But what if only tiny amounts of industrial chemicals are present and living creatures are apparently unaffected? Is the water polluted?

Some would say “yes,” arguing that chronic effects could result, i.e., adverse effects resulting from long-term exposure to even very low concentrations of a substance.

 ▪ The word waste differs from pollutant, although a waste can be a pollutant too. Waste refers to material such as garbage, trash, construction debris: materials that have reached the end of their useful life.

▪ See bellow a description of how pollutant concentrations are described.

Pollution is often less obvious if you live in a wealthy country where the twentieth century brought cleaner air and drinking water, sewage treatment, safe food laws, and food refrigeration. But it took many years and many billions of dollars to reach those results. And wealth does not guarantee an unspoiled environment. For example, parts of the American Appalachian Mountains suffer destruction and pollution resulting from mountaintop removal mining. Or think about wealthy Hong Kong. In the 1990s, the beaches of this island were too polluted for swimming. High concentrations of hazardous industrial metals, livestock waste, and human waste polluted its rivers, and large amounts of trash polluted the harbor. However, between 1993 and 2000, hazardous metal discharges were reduced from 15 432 lb/day (7000 kg/day) to 4409 lb/day (2000 kg/day). And, Hong Kong increasingly collects and treats sewage before releasing it into the harbor. However, air pollution remains critical. In the mid-1990s, exhausts from motor vehicles resulted in 25% of the population suffering from respiratory problems. Today, despite better air pollution controls, heavy smog often blankets Hong Kong. Up to half of this enters Hong Kong from nearby Chinese cities in Guangdong Province. But part of the imported pollution comes from facilities owned by Hong Kong companies - operating on the mainland with poor pollution controls.

Terms used to describe pollutant concentration

ppm = parts per milliona

ppb = parts per billion (one thousand times smaller than ppm)

ppt = parts per trillion (1 million times smaller than ppm)

ppq = parts per quadrillion (1 billion times smaller than ppm)

To grasp these concentrations, consider the following:

1 ppm = 1 pound contaminant in 500 tons (1 million pounds)

1 ppb = 1 pound of contaminant in 500 000 tons

1 ppt = 1 pound of contaminant in 500 000 000 tons

1 ppq = 1 pound of contaminant in 500 000 000 000 tons.

For a different perspective, think about periods of time:

1 ppm is equivalent to 1 second in 11.6 days

1 ppb is equivalent to 1 second in 32 years

1 ppt is equivalent to 1 second in 32 000 years

1 ppq is equivalent to 1 second in 32 000 000 years.

a ppm, ppb, etc. refer to parts by weight in soil, water, or food. In air, they refer to parts per volume.

 Why does pollution happen?

Unless you assume that people and industry deliberately pollute, why does pollution occur? It happens because no process is 100% efficient. Consider your own body - it cannot use 100% of the food you eat.

▪ The gastrointestinal (GI) tract does not break down the fiber in the food you eat, and this is excreted from the body as solid waste.

▪ Enzymes in the gut do break down other foods into molecules that can cross the GI wall into the bloodstream, which carries the nutrition throughout your body. But the body cannot use 100% of the nutrient value, and a portion is excreted into urine as water-soluble waste.

▪ Also, your body cannot convert all the potential energy in food into useful energy- part becomes waste energy.

As with your body, no other process, natural or human, such as manufacturing or fuel burning, is 100% efficient: each produces pollution and waste, and waste energy. Lack of prevention, carelessness, unwillingness to invest in good technology, or lack of appropriate technology aggravates the waste and pollution produced. Architect William McDonough and chemist Michael Braungart observe, “Pollution is a symbol of design failure.” In other words, wastes need not be wastes and pollutants need not be pollutants. We should be able to return these to the manufacturing process, or else make sure the wastes involved are able to biodegrade harmlessly in the environment. 

Joomla Templates and Joomla Extensions by ZooTemplate.Com
Share

Search

Translate

ar bg ca zh-chs zh-cht cs da nl en et fi fr de el ht he hi hu id it ja ko lv lt no pl pt ro ru sk sl es sv th tr uk vi

Newsletter

Subscribe our Newsletter