"Visions of World Benefit & Global Responsibility: Perspectives of McGill Students

Monday, July 30, 2007


Ever since human civilization existed, we have viewed our environment as the universal dumping ground. We adopted a belief that in its vastness, our impacts to it would be minimal or in some cases, the effects are insignificant as long as it’s not “in our backyard.” However throughout the ages we have begun to realize the dire consequences this kind of behavior has not only to the environment but human health itself. In this day and age pollution has become a global problem and many of our pristine environments have now been contaminated by xenobiotic compounds, some so severely that life has been intoxicated and in other cases become a toxic site. Although new technologies and regulations are preventing such catastrophic situations to arise again, we still remain with areas which are heavily contaminated. In this case the only suitable solution to restoring these areas is through remediation.

The main goals of remediation is to eliminate the site, both land and ground water, from any contaminants, prevent future contamination of said site, remove contamination that may have moved off the site, and finally prevent contamination from leaving the site. There are a wide variety of remediation methods such as hundreds of physical and chemical methods as well as biological ones. As of date, the most cost effective and eco-friendly approach to remediation is biological which is commonly termed as bioremediation. In essence, bioremediation uses bacteria, fungus, and in some cases plants to degrade xenobiotic components affecting a particular site. Of these, the most common organism used is bacteria. The reason why bacteria are commonly used is because unlike any other organism on earth they have had billions of years to evolve into thousands of species. Furthermore, bacteria excel at degrading numerous organic components which they utilize as a carbon and energy source.

The fist case of bioremediation was by cleaning up military sites. With time and knowledge this later expanded to soils contaminated with explosives, pesticides, oil spills and now application to polynuclear aromatic hydrocarbons (PAH) [a very toxic family of chemicals] with an incredible efficiency of approximately 90%. The ability for bacteria to degrade these chemicals have only widen and researchers are constantly finding new bacteria that may be suitable for such purposes or enhancing known bacteria to become better degraders of these components.
It is without a doubt that prevention is more cost-effective than treatment, and this is the case with remediation overall. However, with toxic sites already in existence, the problem can’t be neglected. The costs for remediation vary widely and is dependent on many factors like how “clean” do we want the site to be, volume of the area to be treated, type/s of contaminant/s, extent of contamination, type of treatment option (in-situ, ex-situ) and so forth.

Sadly, once humanity interferes with a pristine site, this location will never achieve its original state. Although bioremediation is an amazing technology that has solved and will continue to solve many toxic sites, once a site has been exposed to xenobiotic compounds it will never be able to achieve its original pristine state. Despite this, it is important to realize that the environment is resilient and even the most toxic of sites like Chernobyl can once again support life, even if it's different from its original state. As we reach the modern age of environmentalism, industry must not “compromise” on tackling the effects its operations have on the environment. The solutions are before our eyes, and despite the cost even if we can only take a given environment to 75% of what it was originally, this 75% less human health repercussions and 75% more life than what existed prior to remediation.

No comments: