Health and environment: A closer look at plastics

http://feeds.sciencedaily.com/~r/sciencedaily/~3/dfTI4MpfEOU/130123133928.htm

Scientists have been following the chemical trail of plastics, quantifying their impact on human health and the environment. In a new overview, researchers detail the risks and societal rewards of plastics and describe strategies to mitigate their negative impacts, through reconsideration of plastic composition, use and disposal.

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New Desktop Plastic Recycling Device Could Make 3D Printing More Planet-Friendly

http://thinkprogress.org.feedsportal.com/c/34726/f/638933/s/27b56911/l/0Lthinkprogress0Borg0Cclimate0C20A130C0A10C20A0C14713510Cnew0Edesktop0Eplastic0Erecycling0Edevice0Ecould0Emake0E3d0Eprinting0Emore0Eplanet0Efriendly0C/story01.htm

The Filabot. Photo by Whitney Trudo. Over the last year or two 3D printing has enjoyed a boom of sorts, as the technology has decreased to a size and price that’s at least somewhat feasible for the average consumer or hobbyist. At the same time the cost of plastic filament — the raw material 3D printers heat and then deposit to fabricate objects — has kept use of the technology beyond the reach of most individuals. But now there’s a new desktop system that not only has the potential to solve the cost-of-filament problem, but to also make 3D printing an ally in efforts to cut down on the average household’s plastic waste. The Filabot was developed by an American college student, Tyler McNaney, who raised raised over three times his initial $10,000 goal with a Kickstarter campaign to get the project off the ground. Aficionados were paying $350 for the first-run version fo the device, which can transform most forms of household plastic waste into filament, as well as recycle failed 3D printing projects for another go-round. Treehugger has the details: The Filabot can turn most types of plastic into filament, including HDPE, LDPE, PET, ABS, PLA and NYLON-101. That means the machine can turn most plastic waste you might have around your house into a building material. Things like milk jugs, soda or water bottles, trays, plastic wraps, water pipes, luggage, packaging, biodegradable plastics and even Legos can become something new. This also means that 3D printed projects gone wrong can also be fed into the Filabot to be made again, giving more room for trial and error without the fear of creating lots of plastic waste. This system lets us imagine a future where we’re not only 3D printing replacements or repair parts for our things instead of throwing them away, but using waste plastic to in the process. Filabot had a successful Kickstarter campaign last year where supporters paid $350 to get a first run version of these machines and the team is slowly working out kinks to get them out to public, though no official price has been released yet. On the other side of the equation — moving 3D printers themselves into the realm of everyday devices Americans keep in their homes — MakerBot recently unveiled a 3D printer for the consumer market. Then Cubify did them one better, releasing a consumer printer that’s smaller, more aesthetic, and, arguably most important, cheaper. To give a few examples of the scale of plastic waste problem: Only 10 percent of the 300 million tons of plastic produced globally each year is recycled. In the United States specifically, 31 million tons were produced in 2010, and only eight percent was recycled. 51 billion plastic bottles are used globally every year, while only one in five are recycled. And plastic bags and cigarettes make up 80 percent of marine litter, and plastic bag litter has become such a huge problem that country’s around the world are taxing or outright banning them. In some ways, the problem may actually be worse in the developed world. For instance, while India’s official government does a poor job dealing with trash, an informal trash economy has sprung up that successfully recycles 56 to 70 percent of the country’s recyclable material. In Europe and the United States, the amount is closer to 30 percent.

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Plastics Suck Up Other Toxins: Double Whammy for Marine Life, Gross for Seafood

http://www.motherjones.com/blue-marble/2013/01/plastics-and-chemicals-they-absorb-pose-double-threat-marine-life

Photo courtesy of Kent K. Barnes / kentkb

Some plastics are worse than others for the marine life that accidentally or intentionally eat them. That's because not only are the plastics themselves toxic but some also act as sponges for other toxins. Unfortunately the most commonly produced plastics also absorb the most chemicals. This according to a new study in early view in Environmental Science & Technology. 

The researchers measured the absorption of persistent organic pollutants (POPs)—specifically polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs)—to the five most common types of mass-produced plastics:

Polyethylene terephthalate (PET). Recycling symbol #1. Example: Water bottles.


High-density polyethylene (HDPE). Recycling symbol #2. Example: Detergent bottles. 


Polyvinyl chloride (PVC). Recycling symbol #3. Example: Clear food packaging. 


Low-density polyethylene (LDPE). Recycling symbol #4. Example: Plastic shopping bags. 


Polypropylene (PP). Recycling symbol #5. Example: Yogurt containers, bottle caps.

From this research it seems that stuff made from polyethylene and polypropylene likely poses a greater risk to marine animals (and presumably the people that eat them) than products made from PET and PVC. Though the authors note that PVC is carcinogenic and toxic all by itself.

Laysan albatross carcass filled with ingested plastic debris, Midway Island. Nearly all carcasses found here have marine debris in them. It's estimated that albatross feed their chicks ~10,000 lbs of marine debris annually on Midway. Andy Collins, NOAA Office of National Marine Sanctuaries

The authors were also surprised to find how long the plastics kept absorbing the contaminants. At one site they estimated it would take 44 months for high-density polyethylene to stop absorbing POPs.
"As the plastic continues to degrade, it's potentially getting more and more hazardous to organisms as they absorb more and more contaminants," says lead author Chelsea Rochman (UC Davis). 
The research was conducted over a year at five sites in San Diego Bay with pellets of each type of plastic immersed in seawater and retrieved periodically for absorption measurements. 
The paper:

Chelsea M. Rochman, Eunha Hoh, Brian T. Hentschel, and Shawn Kaye. Long-Term Field Measurement of Sorption of Organic Contaminants to Five Types of Plastic Pellets: Implications for Plastic Marine Debris. Environmental Science & Technology (2013). 

 

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