ON the first Earth Day, April 22, 1970, as crowds gathered to demand a oneness with nature and effective strategies for preventing pollution, US Secretary of the Interior Walter Hickel announced approval of the trans-Alaskan oil pipeline. Last year, the need for oil and the desire for a clean environment collided when the Exxon Valdez ran aground on Bligh Reef. The catastrophe of that oil spill demonstrated the failure of the US Environmental Protection Agency to fulfill the hopes of many on that original Earth Day.
As Earth Day 1990 approaches, it is interesting to note that efforts to clean up spilled oil may signal a renewed ``back-to-nature'' approach to dealing with pollution.
Bioremediation, the use of biological agents such as bacteria and fungi to remove pollution, was used to treat 70 miles of oil-soaked shoreline in Prince William Sound. EPA Administrator William K. Reilly called the technique ``virtually the only good news to come out of that tragic situation.''
Although the Alaskan oil-spill cleanup represents the most extensive use so far, there have been other successful applications of bioremediation. Nutrients and oxygen have been used to stimulate the microbial breakdown of gasoline contaminants in groundwater. Microorganisms have been added at polluted locations to break down toxic substances such as phenol and creosote.
Using bioremediation to remove pollutants has many advantages. Its by-products, such as water and carbon dioxide, are nontoxic and can be accommodated without harm to the environment and living organisms. The method is cheap, whereas physical methods for decontaminating the environment are extraordinarily expensive.
The physical cleaning of oiled rocks in Prince William Sound, for example, cost Exxon more than $1 million a day and, at that, was only partially successful.
Neither government nor industry can afford to physically clean up the nation's known toxic-waste sites. While current technologies call for moving large quantities of contaminated soil to incinerators, bioremediation can be done on site and requires simple equipment that is readily available.
The biological agents used in bioremediation break down pollutants by acting as natural incinerators. They may be native to the contaminated area, or can be brought to the site.
Through genetic engineering, scientists now can custom design and produce microbial strains that break down specific pollutants at particular sites of contamination. This technique has never been applied, however, partly because the EPA is still struggling after several years of discussion to regulate the way they are released into the environment.
If the emerging industry of bioremediation is to fulfill its promise, the EPA must see that the products and processes of the technique are adequately tested and regulated to protect human health and the environment.
Bioremediation cannot be viewed as a cure-all for environmental pollution. Like other technologies, it has limitations. Microorganisms cannot break down some synthetic pollutants; in other cases, such as the insecticide DDT, they can do so only slowly and under very special conditions.
However, given the imminent threat posed by toxic chemicals, it would be a grave mistake to overlook the potential of bioremediation. It is essential that safe and sane use be made of pollutant-degrading microorganisms, including those that are genetically engineered. When pollution prevention fails, bioremediation should be included in a balanced program to enhance natural cleansing processes.
Bioremediation is a technology that is in harmony with nature. It should play an increasingly important role in the continuing struggle to realize the objectives of Earth Day.