Hobbies And Interests
Wastewater
Wastewater, better known as sewage, is mostly water; the trick is to get rid of the small percentage that is everything else. Once filters and gravity have done their work, bacteria are introduced. They feast on a slurry of fat, sugars and starches, better known as kitchen grease. Bacteria break down the grease hydrocarbons into carbon dioxide and water.
Plastic
Styrene is a toxic byproduct created when plastic foam is made, and we use a lot of plastic foam. Scientists found that a common bacteria, Pseudomonas putida, which usually dwells in the soil, has a hankering for styrene. P. putida eats the carbon in the styrene and converts the rest into PHA, a stretchable plastic that can be reused to coat cardboard or even to build medical implants. Even better, the bug likes to dine on plastic foam, too -- so all those cups and plates that now fill landfills and would otherwise take thousands of years to break down can be recycled efficiently.
Biomass
Biomass, essentially, is anything industry can grow and harvest but we can't eat. Think of cornstalks, nutshells or even grass clippings. The stuff can be buried or burned, but scientists have found a better solution: turn biomass into fuel. Genetically engineered thermophilic bacteria are used. "Thermophilic" means the bacteria like heat, and the hotter the environment, the faster the bacteria work. The little moonshiners feast on sugars present in biomass waste and turn cellulose into ethanol, an alcohol now used in gasoline.
Metals
Bacteria are everywhere; one estimate, funded by the National Science Foundation and the U.S. Department of Energy, guesses there are 5 million trillion trillion of them on Earth -- that's a 5 followed by 30 zeroes' worth of just this one type of microorganism. They like to live in large groups, called colonies, and when bacteria colonies form on metal -- remember, they're everywhere -- they can eat away at the metal. Scientists first noticed a century ago that bacteria corrode lead. They're also partial to stainless steel and other metals. Bacteria can be "slime-forming, acid-producing, sulfate-reducing, nitrate-reducing, iron-oxidizing and iron-reducing," say researchers Sten B. Axelsen and Trond Rogne. They also attract fungi and other living things and trap water that can help turn metal to metal dust. That's a headache for builders and sculptors, but a boon for industries looking for eco-friendly ways to get rid of the heavy-metal waste products of the Industrial Revolution.