Teen Filter Invention to Pull Phosphorus out of Water

Phosphorus is commonly found in agricultural fertilizers, along with manure and other organic wastes including sewage. While it is an essential element for plant life, too much phosphorus in our water can speed up a process known as eutrophication (a reduction in dissolved oxygen within water bodies caused by an increase of mineral and organic nutrients) in streams, rivers and lakes. Soil erosion is one of the biggest contributors of phosphorus in streams. Erosion during floods for example, can transport phosphorus from the river banks and adjacent areas into streams which then carry the water to rivers and lakes.

In urban settings, phosphorus is attached to soil particles and moves into surface water through runoff. Research indicates that phosphorus can also move from groundwater into surface water through streambanks. Scientists are concerned that phosphorus concentrations in groundwater affect the water quality of surface water. A sign of highly eutrophic or phosphorus enriched water is excessive growth of algae in lakes. This excessive growth of algae can lead to diminished levels of oxygen which upset the balance of a sensitive eco-system causing the premature death of organisms including fish. Other negative impacts include changes in the types of algae found. Some algae can release toxins that can directly impact human health in a very negative way.

What can we do to combat this problem and find a way to keep the balance of sensitive eco systems? Future generations may be the key to discovering solutions to many problems in the modern world. This year, the three winners of the 75th annual Intel Science Talent Search (STS) strove to tackle some of the problems faced in the world today. One of those problems is to find a way to clean polluted streams. One teen found local motivation during a chemistry class when she was shocked to find the amount of phosphorus in the local system of waterways. Having been under the impression that the streams were clean she was not expecting to find phosphorous pollution caused by fertilizer in the water runoff.

After collecting data and analyzing seven local streams for a nine month period, the data supported the student’s findings that the highest levels of phosphorus occur directly after a storm when nutrients are being washed in from different places around the city. The student then decided that a viable solution would be to design a filter to pull the phosphorus directly out of the water. The teen set about designing a filter that was not only tiny in size (about the size of a quarter) but also designed to pack a great deal of punch. It is made from alginate; a molecule that is found in brown seaweed which is then mixed with magnesium and aluminum. When phosphorus in the water comes into contact with the metals it combines with them. These metals precipitate out of the water and become solid making them easily removed. Although simple in design it has proven to be very effective in removing phosphorus from the water. Texas Heritage Protection applauds the innovation and ingenuity of the next generation and can’t wait to see what solutions they come up with next!