Almost everyone has seen photos of wildlife trapped in oil spills. Here is an experiment to show the science of how oil and soap interact.
Materials: dish soap, plastic shopping bag, wax paper and a large bowl filled with water.
Process: Tear the wax paper into small pieces and place in the plastic bag. Tie the plastic bag shut tight. Float the bag on the bowl of water. Add a few squirts of dish soap to the water.
Result: The wax paper and the plastic bag float because just like a duck, they are water repellent. The oil in a duck's feathers repeals water and helps the duck to float. When you add the dish soap, the bag sinks. Why? The liquid soap allows water to stick to the oil repellent on the bag and wax paper and thus removes it's ability to float.
How does the soap used to clean birds soaked in oil cause damage to the environment? All soap released in fresh water from washing a car and letting the rinse water run into the storm drain to washing dishes from a campsite at the river KILLS fish. Here are the facts: " Detergents can have poisonous effects in all types of aquatic life if they are present in sufficient quantities, and this includes the biodegradable detergents. All detergents destroy the external mucus layers that protect the fish from bacteria and parasites; plus they can cause severe damage to the gills. Most fish will die when detergent concentrations approach 15 parts per million. Detergent concentrations as low as 5 ppm will kill fish eggs. Surfactant detergents are implicated in decreasing the breeding ability of aquatic organisms. Detergents also add another problem for aquatic life by lowering the surface tension of the water. Organic chemicals such as pesticides and phenols are then much more easily absorbed by the fish. A detergent concentration of only 2 ppm can cause fish to absorb double the amount of chemicals they would normally absorb, although that concentration itself is not high enough to affect fish directly. Phosphates in detergents can lead to freshwater algal blooms that releases toxins and deplete oxygen in waterways. When the algae decompose, they use up the oxygen available for aquatic life." Source - https://www.lenntech.com/aquatic/detergents.htm
