Microorganisms can assist with accelerating the biodegradation of oil spills especially along shorelines. Clean-up crews can (& do!) accelerate this process either by adding fertilisers which encourage microbial growth or by introducing specially engineered microorganism which are purpose built to eat oil… BUT!!
Despite the success of bioremediation technology applications in groundwater remediation, a number of issues have been identified with the use of additives in bioremediation.
These include biofouling, stalling, system bypassing or short circuiting, reduction in hydraulic conductivity, contaminant plume displacement and dilution as well as pH and secondary water quality issues.
Microbes are typically included to stimulate microorganism growth and accelerate contaminant degradation in engineered bioremediation systems.
Other common additives used in engineered bioremediation include organic carbon, oxygen, nutrients, and pH modifiers. Organic carbon substrate is the most important and widely used additive.
Too much substrate generates organic acids and causes decreases in the pH of groundwater. In addition, anaerobic reductive dechlorination generates HCl that could also decrease groundwater pH.
A decrease in pH to the acidic range could potentially mobilize metals (notably iron, manganese) and metalloids (arsenic), creating secondary water quality issues and could also inhibit growth of bacteria communities such as Dehalococcoides, thereby stopping the bioremediation process.
If nitrate is used, by products including nitrite, nitric oxide, nitrous oxide, and nitrogen gas could be generated. (The predominant by product depends on the enzymes possessed by the microbes, present.)
Changes in redox conditions can also enhance solubilization of metals and promote the formation of the following undesirable products (e.g., hydrogen sulphide and methane gases) Ref 
OSE II is the Only Approved (Ecologically safe) Bioremediation agent for use on Land, Water & Sea by the UK’s Marine Management Organisation (MMO)
The world's most environmentally safe and cost effective treatment for hazardous waste, spills and contamination
Oil Spill Eater II : the natural solution! Oil Spill Eater II (OSE II) is the world's most environmentally safe and cost effective...
When OSE II is applied to an oil spill, the oil’s molecular structure begins to breakdown immediately and in a short time, visually disappears.
Bio surfactants help by connecting with the oil molecules and breaking down the covalent and ionic bonds, creating small micelles (oil droplets). The process rapidly reduces the toxicity of the oil, making it more bioavailable to indigenous bacteria that then utilise the oil as a food source.
A one step cleaning procedure; usually there is no need for additional cleaning processes, such as collecting with booms & skimmers or disposing of effluent!
Part 4 in our series of articles clarifies the differences & benefits of using OSE II as your Bioremediation solution of choice " - WHY OIL SPILL EATER INSTEAD OF FERTILIZERS?
CLEANING · CONTAINMENT · ABSORPTION · REMEDIATION
For oil spills far out in the ocean sometimes the best strategy is to do nothing. If there is no chance of the spill reaching land or drifting too close to sensitive marine areas, it can be safely left to disperse and biodegrade through natural processes.
In some situations, it may be possible to surround all or part of the oil spill with booms preventing it from spreading uncontrollably. Booms can also be used to block an oil slick from entering vulnerable or sensitive areas such as inlets, fishing grounds or shoreline infrastructure. Once contained the oil can be collected by skimmers and sorbents or sometimes burnt in situ!
The use of chemical dispersants has always been controversial. Dispersants act by reducing the surface tension that stops oil and water from mixing. This allows wind and wave action to mix the two together with much of the oil sinking below the surface. From there it biodegrades over time. The introduction of oil below the water surface, however, can affect marine life including deep-water corals and sea grass. It can also cause oil to be temporarily accumulated by subtidal seafood. The dispersant itself can also be toxic to marine life as well as humans.
Microorganisms have proven to be the most effective & cleanest means to accelerate the biodegradation of oil – especially along shorelines. Clean-up crews typically accelerate this process by adding fertilizers which encourage microbial growth or by introducing specially engineered microorganism which are purpose built to eat oil.
(Please refer to Article 3 “Concerns over the use of Additives in Bioremediation”)
Oil spill dispersants can be effective in accelerating the break-up and biodegradation of an oil spill; however there is much controversy over their use. Dispersants are designed to reduce the amount of surface oil by allowing it to mix with the water column. Doing this may push much of the oil out of sight (and out of mind); however, it is widely agreed that the process causes more unseen environmental damage than the original oil spill would have on its own.
“The key difference between dispersant and surfactant is that the dispersant improves the separation of particles in a suspension whereas the surfactant is a substance that can lower the surface tension between two phases of matter.. But all surfactants are not dispersants”
By emulsifying oil and seawater, chemical dispersants make that oil more bio-available to sea life – especially small organisms. A recent study published in the Environmental Pollution journal has found this can make the spill 52 times more toxic than the oil alone.
This increased toxicity has the capacity to effect marine life throughout the food chain including planktons and other microorganisms, sea grasses and shellfish, which in-turn affect larger marine animals who rely on them as part of the ecosystem. By upsetting the very fabric of the marine ecosystem, sea life as big as whales can be adversely affected by the use of chemical dispersants. It can also have disastrous results for communities who rely on seafood for their livelihood and diet.
In shallow water, dispersants can be so destructive that they are banned by many environmental authorities.
In these areas the sinking oil causes an oil slurry to build up on the sea floor. This slurry can coat plants, crustacean and corals with a toxic film causing untold environmental damage.
Sadly the use of traditional dispersants will remain popular amongst many stakeholders in an oil spill situation because it does help prevent surface oil from reaching beaches or affecting birds and surface life such as dolphins and penguins. In an effort to prevent these sad images from appearing on TV, however, some oil spill response plans may be causing far more serious problems beneath the ocean surface – where the most marine life exists.
CLEANING · CONTAINMENT · ABSORPTION · REMEDIATION