By releasing damaging oil break-down products into the water, dispersants create a poisonous habitat for fish. According to several laboratory investigations on a number of species, dispersed oil has been demonstrated to be hazardous to fish at all life stages, from eggs to larval fish to adults. It can cause liver damage, impede the immune system, and interfere with brain functions.
Dispersants also tend to move around in the environment more quickly than oil, which increases the likelihood that it will find its way into surface waters where it can do harm. Finally, because dispersants were not intended for use in open waters, they may actually enhance the amount of oil that reaches shoreline areas by reducing the amount of oil lost into the ocean.
While the dangers associated with dispersants are clear, their benefits as an oil spill response tool cannot be ignored. Dispersants help oil spill responders deal more effectively with large spills by breaking down the slick so that it can be cleaned up using traditional methods rather than burning it off like natural gas. This preserves wildlife resources and allows time to deploy additional cleanup techniques such as skimmers and booms.
Additionally, since dispersants reduce the amount of oil spilled, they lower the risk of contamination in nearby waters. There have been reports of dispersant helping oil reach shorelines more quickly due to their effects on wind and wave patterns, but evidence suggests that this benefit does not outweigh the risks of using them.
Dispersants and scattered oil are especially harmful to corals, prompting experts to advocate for a ban on the use of dispersants near coral reefs. Oil spill cleanup crews also use absorbent materials like straw and vegetative matter in an effort to contain the damage caused by dispersed oil. This practice is called skimming and is commonly used after major spills. Skimmed material needs to be disposed of as hazardous waste.
Dispersants help empty out oil that has been spilled onto land or into water bodies. The thick layer of oil makes it difficult for sunlight, oxygen, or natural bacteria to get at the oil beneath the surface. When oil is spilled into water, dispersants prevent it from forming large clumps that would sink or float away from shoreline. This allows the oil to spread out over a larger area and reduces its impact when burned or evaporated.
When oil spills occur close to beaches with high concentrations of vulnerable species, dispersants are used to avoid scaring off wildlife. Without the dispersant, more birds and other animals would likely drown in the spreading oil than survive once they reach shore. Dispersants also allow oil to be cleaned up more easily since it doesn't stick to anything.
Dispersants are chemicals that are sprayed on the surface of an oil slick to break it down into tiny droplets that can mix with the water more easily. While dispersants make the oil leak less apparent, both dispersants and scattered oil beneath the ocean's surface are harmful to marine life. Dispersants also contain alcohol or acids that are toxic if they get into the ocean water.
How do they work? When oil spills occur, the first thing people usually think about is how to stop the leak immediately. But once the initial shock has worn off, officials have to figure out what to do about the mess left behind. There are two types of dispersants: organic and inorganic. Organic dispersants are natural products such as soybean oil or wood pulp that break down over time into smaller molecules that are absorbed by water. Inorganic dispersants are chemical compounds that do the same job as organic dispersants but are not as stable so they need to be added to the oil periodically to maintain their effectiveness.
Who uses them and why? Oil companies use dispersants because it's easier for them to deal with a spill if the liquid part (the oil) is broken down into small droplets. This makes it possible to pour absorbent materials such as sand onto the spill instead of trying to soak up the oil with towels or other methods. Dispersants also help minimize damage to shorelines and prevent sensitive wildlife habitats from being polluted by the oil.