Nature's Cleaning: Microbes

Aside from all the chemicals and gadgets that humans have produced to clean up spills, nature has a way of cleaning itself. One of the most interesting techniques for cleaning spills involves speeding up a process that has been around since millions of years before man. Biodegradation is a natural process by which microbes alter and break down complex compounds into simpler substances to gain energy and nutrients. The resulting products can be carbon dioxide, water and simpler compounds that do not affect the environment.

Microbes include bacteria, archaea, fungi and protists. Viruses might also be categorized as a major type of microbe, though there is debate as to whether viruses can be considered living creatures.

Microbiologists have found microbes living just about everywhere, including in soil, water, air, animals, plants, rocks and even in humans. A handful of garden soil contains hundreds if not thousands of different kinds of microbes. A single teaspoon of that soil contains over 1,000,000,000 bacteria, about 120,000 fungi and 25,000 algae. Microbes have been around for billions of years because they are able to adapt to the ever-changing environment.

However, the biodegradation process is relatively slow, and when an oil spill occurs, workers must act fast to protect the environment. Speeding up the process can be accomplished in two ways: adding fertilizing (nutrients) and/or seeding (adding more microbes). When technology is used to speed up the process, it is known as bioremediation. In recent years, the U.S. Environmental Protection Agency has determined that bioremediation is a safe and effective oil-removal option.

Oil isn’t the only substance tested for cleanup by microbes. Certain U.S. Army installations have tested the effectiveness of using microbes to remove explosive products deposited in soil after years of ammunition manufacturing and disposal. First the explosives-tainted soil is mixed with water and placed in a treatment container. The mixture is given regular doses of oxygen and a food source, which spur growth in microbes that already live in the soil. While “eating” the food, the microbes break down the explosives so the soil can be returned to its original site.

Even the most complex science can’t make up for the birds, animals and beaches that have been harmed by oil spills. That’s why prevention is being stressed more and more. The oil industry is coming up with safer ways to produce, transport and store oil. Safer vessel designs play a big role. Examples include double hulls, improved steering systems, improved radar detection systems, satellite and radio communication and computer monitoring of the vessel’s operations. Better aids for navigation systems also help reduce risks.

“Biological Remediation Overview.” Environmental Directions, Inc. 1998. “Cleaning Up with Bacteria.” Discovery Channel School. 1999. Discovery Channel Communications, Inc. 27 May 2000. http://www.teachingtools.com/CrudeEnergy/OilEnvironment.htm