Most of us do not realize the importance and functionality of diatomaceous earth.
DE often is referred to as the workhorse of the filtration industry, clarifying nearly every type of liquid, including beer, juice, edible oils, pharmaceuticals and many other important products.
So where does diatomaceous earth come from? DE is composed of the fused frustules of single cell plants called diatoms. These diatoms are considered the beginning of the food chain in our oceans and are responsible for sequestering much of the world’s atmospheric CO2. Life on earth would not exist as we know it today without DE. The vast majority of today’s commercially available DE were formed three to 12 million years ago.
How did DE start being used for swimming pool filtration?
DE got its big break in Hollywood in the 1930s. During filming of the popular Esther Williams’ aqua musicals, the pool water continuously needed to be replaced due to cloudiness. The studios enlisted local engineers who developed the first commercial pool filter. Following much experimentation, they selected DE as the ideal media to keep the water clear for filming.
From those early days, pool builders quickly caught on to the idea of DE filtration. The beautiful pool images created demand and led to the rapid growth of the residential pool industry.
A crypto catcher?
DE is capable of removing particles as small as 2- to 3 microns. Cryptosporidium is a pathogen measuring about five microns in diameter and seven in length. That makes DE an effective way to capture crypto.
In 1993, following an outbreak of cryptosporidium in Milwaukee, the New England Journal of Medicine published a study investigating the best remedy for treating water contaminated with cryptosporidium or giardia. It was concluded that DE was the most effective treatment system. Another study conducted by the University of North Carolina confirmed the superior removal efficiency of DE in swimming pool applications. The UNC study found that DE had a 99.4 percent effectiveness rating in pathogen removal efficiency.
Why does DE get a bad rap?
Diatomaceous earth is a light-weight mineral with a large percentage of void space. Thus, it is ideally suited for liquid filtration but also prone to dust concerns.
DE is a Class 1 carcinogen, but only when airborne. That fact seems to get lost when discussing any potential health risks associated with the product. Other Class 1 carcinogens include beach sand, filter sand, plaster dust and sawdust.
Chances are good you ingest trace amounts of DE through beer or soda. And that’s perfectly safe. The U.S. Food and Drug Administration has classified DE as an “incidental food additive,” given that its so common in the beverage industry that there’s always the chance of consuming minuscule amounts.
When preparing to apply DE into a filter, the operator should wear a dust mask and prepare a slurry of DE for addition to the filter system. Once DE has been wetted, the hazard is eliminated. Spills are easily cleaned up when washed away with water, avoiding any dust creation when swept up with a broom.
Mastrup is the director of filtration technology at EP Minerals in Reno, Nev.
