More specifically, groundwater represents 98% of the available fresh water on earth. The contamination of groundwater has increased significantly due to industrial developments over the last century. To illustrate how the modern human has had an impact on the environment, let us look at some numbers: In the United States alone, yearly 100 million tons of hazardous waste is generated and 4 million tons of toxic chemicals are released into streams; in addition, 1.2 million tons of toxic waste are emptied into landfills and 1.5 million tons are injected into deep wells for disposal. Again in the United States, of the 2 million underground storage tanks in gas stations, 450,000 are leaking gasoline and petroleum products to the subsurface. If these numbers do not impress you, remediation costs for contaminated sites in Europe are expected to exceed $1.5 trillion in the near future. These are only some of the impacts of heavy industrialization of which we are aware. The contaminants that are released into the environment severely threaten drinking water, agricultural, and surface waters.

The pollution process of the subsurface environment is ironically simple. Leaks from various contamination sources seep into the groundwater from where they travel and infiltrate the soil with which they come in contact. Contaminated soils and sediments slowly release these pollutants, which over long period of time have become a continuous source. Of course, all these contaminants can potentially cause cancer or have detrimental effects on the ecosystem or on human health. To give an example of how these pollutants easily spread around the globe, in a recent study of dairy products that were collected from countries all around the world, the same type of organic contaminant (PCB:

Polychlorinated Biphenyls) was found in those products that, for the most part, originated in the USA, although the usage and production of this contaminant has been banned since 1976. How have these pollutants managed to persist in the environment and travel all the way from USA to the rest of the world, even as far as Australia? There are several ways this can be done; first the released contaminant volatilizes into the air and travels, through atmospheric depositions of large quantities onto the grass that is eaten by the cow. Another way is that a fish swimming in contaminated fresh water is caught and becomes food at a dairy farm. This research exemplifies how the pollution of the environment can affect us, regardless of where we live on this planet.

It seems like a very gloomy picture though, if nobody is going to take any action against the contamination or clean up the toxic chemicals from vulnerable targets like drinking water sources or terrestrial lands. There are, of course, many precautions that have been undertaken to clean up the environment. This article is about one of the interesting ways in which we utilize microorganisms to clean up contaminated groundwater or drinking water.

It sounds a little strange for engineers to be dealing with bacteria that naturally exist and utilize them in cleaning up the environment. But this is what they are doing, using a technique called bioremediation, wherein natural microbes become stewards for destroying the pollutants in the environment. The simple technical description of bioremediation is the intentional use of the biodegradation process to eliminate environmental pollutants that have been intentionally or inadvertently released. The biodegradation used here is the microbial transformation process of toxic chemicals into nontoxic forms and sometimes mineralization into inorganic elements like carbon, oxygen and hydrogen.

This transformation, which is essentially a process of destruction, first requires the presence of microorganisms. These microorganisms almost always exist in nature, unless there are harsh conditions that prevent microbial growth. The microorganisms use inorganic or organic contaminants as their nutritional and growth source in the life cycle. For example, a commonly encountered organic contaminant, benzene, is composed of six carbon atoms and six hydrogen atoms. During the degradation process, the microorganisms synthesize enzymes that stimulate the breaking down of benzene into carbon dioxide and water or sometimes the simple elements of carbon and oxygen. These enzymes ease the reactions that produce cellular energy and the building blocks for the synthesis of new cells. In essence, the contaminant serves as a nutrient – food – so that the microorganism can continue its life.

The electron acceptors

During the process in which the microorganism feeds on the contaminant (the degradation process), the key issue is the electron acceptors, the complementary part of the chemical reaction that occurs during the biodegradation process. During the breaking down of the large organic molecules into small elements, excess electrons are released into the environment and therefore an electron acceptor is required to maintain the chemical equilibrium and continue the reaction mechanism. This necessity for oxygen or iron dioxide resembles the need for oxygen in our liver to break down the complex molecules that occur during energy production and new cell generation. The process is as simple as this: we breathe oxygen to live and so do microorganisms. Oxygen molecules act as convenient electron dumps for bacteria that usually lie near the soil surface. Depending on the electron acceptor types, degradation reactions are categorized as aerobic (using oxygen) or anaerobic (using nitrate, manganese, iron and sulfate as electron acceptors). Humans can only inhale oxygen, but most insects can utilize other molecules, like iron oxide or sulfur as well.

Moreover, in order to have a successful clean up, scientists need to satisfy chemical and nutritional requirements and this is challenging for engineers. As these electron acceptors are not always readily available, engineers supplement the electron acceptors in the contaminated environment by methods like pumping air into the ground. Sometimes the microorganisms that are necessary to degrade the potential pollutant do not exist and the engineers must first inject the bacteria so that they can consume the pollutants as food.

Geobacter

One of the microorganisms most frequently studied for its degradation potential for organic and inorganic contaminants is Geobacter metallireducens, or the geobacter. Since it was first discovered, more than 20 years ago, researchers at the University of Massachusetts have been studying this incredible creature; however, they admit that there are many things that they still do not know about it. The geobacter was the first organism found to oxidize organic compounds to carbon dioxide using iron oxides as the electron acceptor. In other words, the geobacter gains its energy by using iron oxides (a rust-like mineral) in the same way that humans use oxygen. The main nutrient for the geobacter can be organic or inorganic pollutants for, and it breathes iron oxide in the way the human inhales oxygen. The geobacter can consume soil and groundwater contaminants like benzene and the gasoline additive MBTE, even in an oxygen-free environment. The geobacter, which has been found almost everywhere, even living in the dental spit-sinks, also flourishes in uranium-contaminated sites, converting soluble radioactive material to a material that is insoluble in groundwater, therefore making it easier to isolate for cleaning up. At present the geobacter is being put to work in actual clean up projects. As our understanding of the functioning of the species has improved, it has become possible to use this information to modify environmental conditions in order to accelerate the rate of contaminant degradation.

More interestingly, researchers have discovered that the geobacter spits out unwanted electrons into the circuit while consuming contaminants for energy. The geobacter exhales electricity through 20 to 30 hair-like structures, just 3 to 5 nanometers in diameter, to its surroundings. Although there is hardly enough microbe-produced electricity generated to solve the world’s energy problems, a fuel cell measuring a cubic meter would generate 2 kilowatts, and some engineers are talking about powering sewage treatment plants with a type of geobacter that harvests off the sewage itself. Just to give an idea about the direction of future research, researchers are now working on a selected gene of the geobacter. The gene that limits electricity production will be modified so that electricity production can be boosted during the degradation process. Given that, it would not be surprising if there were technology that created energy while cleaning contaminated soil or groundwater.

Clean water is a basic need for every human being, and it is our moral obligation to work as stewards for the environment; the first thing we must do is to stop contaminating the planet. However, we are faced with resources that have been previously contaminated. As one result of an increasing sense of responsibility toward nature, we are at a point where we can use natural microorganisms or plants as clean-up tools. Although mankind harshly contaminates the environment while creating an industrial and technological world, it is quite ironic that we still rely on the marvels of such divinely ordained solutions to sustain life.

References

• Martin Alexander, Biodegradation and Bioremediation, 199, Academic Press, San Diego CA USA
• Pedro J. Alvarez, Walter A. Illman, Bioremediation and Natural Attenuation: Process Fundamentals and Mathematical Models, 2005, Wiley and Sons, NY, USA
• www.geobacter.org Geobacter project, University of Massachusetts, Amherst Environmental Biotechnology Center
• Jana Weiss, Olaf Papke, and Ake Bergman, A Worldwide Survey of Polychlorinated Dibenzo-p-dioxins, Dibenzofurans, and Related Contaminants in Butter, AMBIO: A Journal of the Human Environment Volume 34, Issue 8 (December 2005), pp. 589–597

The environmental crisis humanity faces at this stage in their development is an outward manifestation of the internal crisis arising from the break with traditional beliefs and values, and their surrender to the disease of ‘problem denial’ characteristic of modern urban, industrialized societies. This state of mental and spiritual sickness takes man down a vicious and destructive spiral. Human-centred, short-term gain and economic surplus-oriented societies have led people to put their trust in science and technology to solve their problems, regardless of the cost to ‘others’. This way of life is not sustainable and creates new and worsening problems, doing perhaps inevitable long term damage to ‘other’ people, other species, the environment as a whole.

Industrialization has led to a simplified, throw-it-away world view which encourages people to dominate and manipulate all available resources in a frantic race for growth in levels of self-indulgence. The causes of environmental overload or degradation are pollution of water, air and land, and depletion of resources. Urbanization and industrialization where large amounts of pollutants are concentrated in small volumes of air, water and land have led to the overloading and disruption of the natural dilution, breakdown and recycling of the chemicals essential for life. The effluent of fertilizers, pesticides, toxic heavy metals, and (partly or wholly) treated industrial waste, is allowed to run off into lakes and streams. The effects are already very tangible: nauseating smells and tastes, smog causing reduced atmospheric visibility, corrosion of metal work, erosion of buildings; reduced tree and crop production; a decrease in biodiversity-each year at least 51,000 species in all become extinct, often as direct consequence of human activity; serious damage to human health-as in the spread of infectious diseases, irritation and diseases of the respiratory system, genetic and reproductive defects, and cancers (for example of skin and liver).

The scale and rate of environmental degradation demand serious and urgent reform. We desperately need to change our attitudes and concepts conform more with the laws of nature as ordained by God. Only if we do it so can we hope for true success in this world and the Hereafter.

As noted, excessive and wasteful use of material resources is a major factor in environmental degradation. We have three types of material resources. First, deep-mined non-renewable (exhaustible) resources such as petroleum, coal, natural gas, and minerals such as copper, aluminium, iron, and uranium which are purified from ores supplied by the earth’s crust. Fossil fuels are finite and could be exhausted quite quickly at present rates of consumption; further, when burned, these fuels are converted to waste heat and exhaust gases which are serious pollutants.

Second, there are perpetual resources, namely solar energy, wind power, geothermal energy, and flowing water. These must become our main future sources of energy.

Third, the potentially renewable resources so-called because, they can be replaced through natural processes on a human life-time scale. Examples are trees in forests, grasses, wild animals, fresh surface water, in lakes and streams, and most ground water, the earth’s most valuable resource. If these resources are used at a rate that does not reduce their availability, they can yield a sustainable source of energy. However, when the natural replacement rate is exceeded, then the supply is depleted and environmental degradation results. Some examples are typified by the covering of productive land with water, concrete, asphalt, or buildings to such an extent that crop growth declines and wildlife habitats are lost. Excessive removal of fresh water from aquifers and from surface waters leads to water scarcity. Deforestation without adequate replanting causes destruction of wildlife habitats where timber-growth cannot be sustained.

Alarmingly, nearly half of the world’s original expanse of tropical forests have been cleared. Each year, about 171,000 km2 of tropical forest are destroyed. These losses reduce biodiversity because niches for thousands of plants and animals are destroyed with the trees.

Around 35% of the world’s coastal and inland wetlands have been drained, built upon, or seriously polluted (e.g. the ‘Golden Horn’ in Istanbul). Most of our wastes accumulate in the oceans. Oil slicks, floating plastic debris, polluted estuaries and beaches, contaminated fish, are just a few of the ugly scenes that result. However, man’s carelessness not only affects other species: world-wide, an estimated 16 million people lose their homes and land due to environmental degradation alone.

Resource depletion or scarcity can be absolute or relative. Absolute scarcity occurs when supplies of a resource .are insufficient or too expensive to meet present or anticipated future demands. For example, the world’s finite supplies of petroleum oil may be used up within the next 50 years decades at present rates of consumption. Relative scarcity occurs as a result of unbalanced and inequitable distribution of a resource which, if equitably distributed would meet the demand of everyone in need.

Relative scarcity dominates the world scene at present: industrialized economies of the West, the United States especially consume a huge disproportionate share of material and energy resources at the expense of other nations. This further widens the gap between the rich and the poor countries. It is a fact that the rate of damage inflicted upon the environment, and hence the damage to the stability and security of others’ lives, has been greater in this past century than since the beginning of man’s history. The Muslim World today, once the pioneer of true civilization is being steadily corrupted by serving the lifestyle of the Western powers. The balanced, traditional lifestyle which conforms with the law of God and hence is more environment-friendly nature is being eroded at alarming speed. The Muslims and other victims of modern civilization lack control over their lives, once self-sustaining, and are forced into the global ‘cash economy’ manipulated by a small, cynical elite who gamble, quite literally, with commodity and stock prices without the least concern for the millions of human lives disrupted and destroyed as a result.

Mankind are heading toward an abyss of anxiety and insecurity while the natural world deteriorates around them. Unless we make a concerted and sustained effort to recover the fitrah state, a life-style that accords with the balance and order of creation, destruction and disorder on a hitherto unimagined scale await us in this life and, in the next, the torment of knowing we failed our responsibility. For in that life we shall be questioned in detail about what we did in this; each of our senses and limbs and organs will bear witness against us; and we will account even for every drop of water we used well or wasted.