OTA: STEP UP SPILL BIOREMEDIATION RESEARCH

More research is needed to explore promising bioremediation techniques to combat oil spills, says the congressional Office of Technology Assessment. An OTA study said the U.S. government and industry should coordinate research on use of microorganisms to speed degradation of oil or other contaminants.

June 24, 1991

2 min read

More research is needed to explore promising bioremediation techniques to combat oil spills, says the congressional Office of Technology Assessment.

An OTA study said the U.S. government and industry should coordinate research on use of microorganisms to speed degradation of oil or other contaminants.

OTA said, "Although considerable research has been conducted in the last 10 years on development of bioremediation techniques, important questions remain about their effectiveness, possible unintended side effects of their use, and their importance in comparison with more conventional oil spill response technologies.

"Research concerning these issues has been given new momentum, in large part because the Exxon Valdez accident stimulated a general search for more effective methods to fight oil spills."

OTA said mechanical spill cleanup technologies are likely to remain the mainstay of the oil response arsenal.

But in certain nonemergency situations-cleaning lightly to moderately oiled beaches, for example-bioremediation could be used as the main technology. Mechanical methods, dispersants, and possibly in situ burning will most likely remain more appropriate technologies for immediate response to spills at sea.

BIOREMEDIATION METHODS

Potential bioremediation approaches for marine oil spills fall into three categories: stimulation of indigenous microorganisms by adding nutrients (fertilization), introduction of special assemblages of naturally occurring oil degrading microorganisms (seeding), and introduction of genetically engineered microorganisms.

OTA said the fertilization approach appears to be the most promising one because experiments suggest that biodegradation of oil spills in most marine environments is constrained by lack of nutri-ents rather than by absence of oil degrading microbes.

It said addition of nutrients on beaches fouled by the Exxon Valdez spill at least doubled the natural rate of biodegradation.

Studies have not been done on bioremediation of spills at sea, partly because of the difficulty of conducting controlled experiments and monitoring in the open ocean.

OTA said no significant harm from use of bioremediation methods for oil spill cleanup has appeared, and it may be a less intrusive approach than other methods.