Environmental microbiology is the branch of microbiology that studies the role of microorganisms in the maintenance of a healthy, quality, and sustainable environment. It is the study of the composition and physiology of microbial communities in the environment inclusive of the soil, water and air; and environmental microbiologists examine the environment and test it for possible microbial contamination that may pose a public health threat. Microorganisms play tremendous roles in the environment especially as it relates to nutrient recycling, biodegradation of organic matters, and even in bioremediation such as the use of specific group of microorganisms to control and remedy the untoward effects of oil spillage in the environment.
Bioremediation is simply defined as the biotechnological clean-up of pollutants in the environment that is microbial-based or driven. Microbial degradation of pollutants (e.g. chemical contaminants, pesticides and hydrocarbons) in the environment unlike other physical degradation processes releases environmentally-friendly substances (e.g. carbondioxide and water) that have minimal or no negative effect on the ecosystem. Most physical degradation processes though rapid may adversely affect the environment negatively when compared to other biological techniques of degradation that employs microbes for pollutant degradation. Some microorganisms are also used to reduce the microbial loads of industrial wastes and sewages, pesticides, and other heavy metals before their release into the environment; and waste waters from industries and domestic homes are also treated with microbes in like manner (Figure 1).
Microorganisms have also been used to treat and recycle organic and inorganic wastes. The activities of microorganisms which help to clean-up the environment and keep it safe and free from contaminants are exploited and studied under this very important branch of microbiology. Pseudomonas species, Sphingomonas species, Wolinella species and other facultative anaerobic or microaerophilic bacteria are some of the microorganisms employed for the degradation of pollutants in the environment. The hydrocarbon-degrading activities of microorganisms have helped to contain the oil spills of coastal regions and the open sea areas where oil spillage is common; and these microbes have assisted in remediating the ecological damage caused by oil pollutants and other wastes.
Microorganisms are a critical part of all public and many industrial wastewater treatment processes because of their innate degradative abilities; and microorganisms have the ability to convert waste products such as waste water to nutrients and minerals and other environmentally-friendly products, thus lessening the impact of such wastes on the environment. Understanding the impact of microbes in the environment assist environmental microbiologists to prevent environmental problems via adequate detection of the harm.
Figure 1: A waste water treatment plant for the treatment of waste waters from industries and domestic homes.
Talaro, Kathleen P (2005). Foundations in Microbiology. 5th edition. McGraw-Hill Companies Inc., New York, USA.
Willey J.M, Sherwood L.M and Woolverton C.J (2008). Harley and Klein’s Microbiology. 7th ed. McGraw-Hill Higher Education, USA.
Rottier E and Ince M (2003). Controlling and Preventing Disease: The Role of Water and Environmental Sanitation Interventions. WEDC Publication, Loughborough University, Leicestershire, UK.
Prescott L.M., Harley J.P and Klein D.A (2005). Microbiology. 6th ed. McGraw Hill Publishers, USA. Pp. 296-299.
Maier R.M, Pepper I.L. and Gerba C.P (2000). Environmental Microbiology. Academic Press, San Diego.
Lapara T.M., Firl S.J., Onan L.J., Ghosh S., Yan T and Sadowsky M.J (2006). Municipal Waste – Water Treatment: A Novel Opportunity to show the Proliferation of Antibiotic – Resistant Bacteria? Fall, 18-23.
Duncan Mara and Nigel Horan (2003). The Handbook of Water and Waste-water Microbiology. Academic Press, UK.