research excerpt pulled from:
http://spectregroup.wordpress.com/2009/09/17/what-eats-plastic/
GARBAGE PATCH IS SIZE OF CONTINENT
http://www.digitaluniverse.net/upcycling/articles/view/135971/
The World’s Largest “Landfill” is the Middle of the Ocean
There is a large part of the central Pacific Ocean that no one ever visits and only a few ever pass through. Sailors avoid it like the plague for it lacks the wind they need to sail. Fisherman leave it alone because its lack of nutrients makes it an oceanic desert. This area includes the “horse latitudes,” where stock transporters in the age of sail got stuck, ran out of food and water and had to jettison their horses and other livestock. Surprisingly, this is the largest ocean realm on our planet, being about the size of Africa – over ten million square miles. A huge mountain of air, which has been heated at the equator, and then begins descending in a gentle clockwise rotation as it approaches the North Pole, creates this ocean realm. The circular winds produce circular ocean currents which spiral into a center where there is a slight down-welling. Scientists know this atmospheric phenomenon as the subtropical high, and the ocean current it creates as the north Pacific central or sub-tropical gyre. Because of the stability of this gentle maelstrom, the largest uniform climatic feature on earth is also an accumulator of the debris of civilization.
If plastic doesn’t biodegrade, what does it do? It “photo-degrades” – a process in which it is broken down by sunlight into smaller and smaller pieces, all of which are still plastic polymers, eventually becoming individual molecules of plastic, still too tough for anything to digest. For the last fifty-odd years, every piece of plastic that has made it from our shores to the Pacific Ocean, has been breaking down and accumulating in the central Pacific gyre. Oceanographers like Curtis Ebbesmeyer, the world’s leading flotsam expert, refer to it as the great Pacific Garbage Patch. The problem is that it is not a patch, it’s the size of a continent, and it’s filling up with floating plastic waste. On our return trip to Santa Barbara, we discovered something never before documented -a Langmuir Windrow of plastic debris. Circular ocean currents with contrary rotation create long lines of material, visible from above as streaks on the ocean. Normally these are formed by planktonic organisms or foam, but we discovered one made of plastic. Everything from huge hawsers to tiny fragments were formed into a miles long line. We picked up hundreds of pounds of netting of all types bailed together in this system along with every type and size of debris imaginable. Sometimes, windrows like this drift down over the Hawaiian Islands. That is when Waimanalo Beach on Oahu gets coated with blue green plastic sand, along with staggering amounts of larger debris. Farther to the northwest, at the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve, monk seals, the most endangered mammal species in the United States, get entangled in debris, especially cheap plastic nets lost or discarded by the fishing industry. Ninety percent of Hawaiian green sea turtles nest here and eat the debris, mistaking it for their natural food, as do Laysan and Black Footed Albatross. Indeed, the stomach contents of Laysan Albatross look like the cigarette lighter shelf at a convenience store they contain so many of them.
It’s not just entanglement and indigestion that are problems caused by plastic debris, however. There is a darker side to pollution of the ocean by ubiquitous plastic fragments.
As these fragments float around, they accumulate the poisons we manufacture for various purposes that are not water-soluble. It turns out that plastic polymers are sponges for DDT, PCBs and nonylphenols -oily toxics that don’t dissolve in seawater. Plastic pellets have been found to accumulate up to one million times the level of these poisons
that are floating in the water itself. These are not like heavy metal poisons which affect the animal that ingests them directly. Rather, they are what might be called “second
generation “ toxics. Animals have evolved receptors for elaborate organic molecules called hormones, which regulate brain activity and reproduction. Hormone receptors
cannot distinguish these toxics from the natural estrogenic hormone, estradiol, and when the pollutants dock at these receptors instead of the natural hormone, they have been shown to have a number of negative effects in everything from birds and fish to humans. The whole issue of hormone disruption is becoming one of, if not the biggest
environmental issue of the 21st Century. Hormone disruption has been implicated in lower sperm counts and higher ratios of females to males in both humans and animals.
Unchecked, this trend is a dead end for any species. A trillion trillion vectors for our worst pollutants are being ingested by the most efficient natural vacuum cleaners nature ever invented, the mucus web feeding jellies and salps (chordate jellies that are the fastest growing multicellular organisms on the planet) out in the middle of the ocean. These organisms are in turn eaten by fish and then, certainly in many cases, by humans. We can grow pesticide free organic produce, but can nature still produce a pesticide free organic fish?”
CANADIAN TEEN DECOMPOSES PLASTIC BAG IN 3 MONTHS
http://blog.wired.com/wiredscience/2008/05/teen-decomposes.html
The Waterloo, Ontario high school junior figured that something must make plastic degrade, even if it does take millennia, and that something was probably bacteria. (At between one-half and 90 percent of Earth’s biomass, bacteria’s a pretty safe bet for any biological mystery.) The Record reports that Burd mixed landfill dirt with yeast and tap water, then added ground plastic and let it stew. The plastic indeed decomposed more quickly than it would in nature; after experimenting with different temperatures and configurations, Burd isolated the microbial munchers. One came from the bacterial genus Pseudomonas, and the other from the genus Sphingomonas. Burd says this should be easy on an industrial scale: all that’s needed is a fermenter, a growth medium and plastic, and the bacteria themselves provide most of the energy by producing heat as they eat. The only waste is water and a bit of carbon dioxide. Amazing stuff. I’ll try to get an interview with this young man who may have managed to solve one of the most intractable environmental dilemmas of our time. And I can’t help but wonder whether his high school already had its prom. If he doesn’t get to be king, there’s no justice in this world.
YEAST, TAP WATER, DIRT
http://news.therecord.com/article/354044
WCI student isolates microbe that lunches on plastic bags
Getting ordinary plastic bags to rot away like banana peels would be an environmental dream come true. After all, we produce 500 billion a year worldwide and they take up to 1,000 years to decompose. Daniel Burd’s project won the top prize at the Canada-Wide Science Fair in Ottawa. He knew plastic does eventually degrade, and figured microorganisms must be behind it. His goal was to isolate the microorganisms that can break down plastic — not an easy task because they don’t exist in high numbers in nature. First, he ground plastic bags into a powder. Next, he used ordinary household chemicals, yeast and tap water to create a solution that would encourage microbe growth. To that, he added the plastic powder and dirt. Then the solution sat in a shaker at 30 degrees. After three months of upping the concentration of plastic-eating microbes, Burd filtered out the remaining plastic powder and put his bacterial culture into three flasks with strips of plastic cut from grocery bags. As a control, he also added plastic to flasks containing boiled and therefore dead bacterial culture. Six weeks later, he weighed the strips of plastic. The control strips were the same. But the ones that had been in the live bacterial culture weighed an average of 17 per cent less. That wasn’t good enough for Burd. To identify the bacteria in his culture, he let them grow on agar plates and found he had four types of microbes. He tested those on more plastic strips and found only the second was capable of significant plastic degradation.
Next, Burd tried mixing his most effective strain with the others. He found strains one and two together produced a 32 per cent weight loss in his plastic strips. His theory is strain one helps strain two reproduce. Tests to identify the strains found strain two was Sphingomonas bacteria and the helper was Pseudomonas. A researcher in Ireland has found Pseudomonas is capable of degrading polystyrene, but as far as Burd and his teacher Mark Menhennet know — and they’ve looked — Burd’s research on polyethelene plastic bags is a first. Next, Burd tested his strains’ effectiveness at different temperatures, concentrations and with the addition of sodium acetate as a ready source of carbon to help bacteria grow. At 37 degrees and optimal bacterial concentration, with a bit of sodium acetate thrown in, Burd achieved 43 per cent degradation within six weeks. The plastic he fished out then was visibly clearer and more brittle, and Burd guesses after six more weeks, it would be gone. He hasn’t tried that yet. To see if his process would work on a larger scale, he tried it with five or six whole bags in a bucket with the bacterial culture. That worked too. Industrial application should be easy, said Burd. “All you need is a fermenter . . . your growth medium, your microbes and your plastic bags.” The inputs are cheap, maintaining the required temperature takes little energy because microbes produce heat as they work, and the only outputs are water and tiny levels of carbon dioxide — each microbe produces only 0.01 per cent of its own infinitesimal weight in carbon dioxide, said Burd. “This is a huge, huge step forward . . . We’re using nature to solve a man-made problem.”
UPCYCLING
http://www.newscientist.com/article/dn14764
Plastic-munching bugs turn waste bottles into cash
Newly discovered bacterial alchemists could help save billions of plastic bottles from landfill. The Pseudomonas strains can convert the low-grade PET plastic used in drinks bottles into a more valuable and biodegradable plastic called PHA. PHA is already used in medical applications, from artery-supporting tubes called stents to wound dressings. The plastic can be processed to have a range of physical properties. However, one of the barriers to PHA reaching wider use is the absence of a way to make it in large quantities. The new bacteria-driven process – termed upcycling – could address that, and make recycling PET bottles more economically attractive.
PREVIOUSLY ON SPECTRE – BIODEGRADABLE PLASTICS
http://spectregroup.wordpress.com/2007/06/22/spectre-investor-biodegradable-plastics/
DOMESTICATING BIOTECH
http://spectregroup.wordpress.com/2007/07/20/domesticating-biotech/
GROW YER OWN BACTERIAL SLAVE ARMY
SEA MONKEYS DONE FOR GOOD
http://spectregroup.wordpress.com/2006/09/05/grow-your-own-bacterial-slave-army-sea-monkeys-done-for-good/
[SHARING IS CARING - Allow us a brief introduction: before we had a name, the Spectre Event Horizon Group used to meet weekly at a bar to commiserate and trade what our business friends call best practices. The group has expanded tremendously since then, but remains premised on smartening the crowd mind. There are no subject limits; a favorite is our sci-fi present, though we like anything that goes toward a better understanding of human behavior + ecology. Our basic idea: to connect minds with mind-blowing information, + create a space for the informal trade of very specialized investigative research, presented for the non-specialist as fair use. The Spectre email list is a moderated open forum. People are encouraged to join and to post. Contact us at spectre.event.horizon.group [at] gmail.com, or to join go to www.spectregroup.org.]
