Unfortunately not all plastic is biodegradable. So we recycle the plastic we can and, in some places, ban what we cannot recycle. That seems logical, as long as we choose what is sustainable over what is profitable.
As we know, plastics differ widely in their chemical structure, properties, and degradability. The plastic identification coding system was introduced by Society of the Plastics Industries (SPI) in 1988. The number in a triangle on the bottom of a plastic container corresponds to a specific polymer composition: 1=PET (polyethylene terephthalate); 2=HDPE (high-density polyethylene); 3=vinyl, PVC (polyvinyl chloride); 4=LDPE (low-density polyethylene); 5=PP (polypropylene), and 6=PS (polystyrene). Although all plastics can be reused to a certain degree, not all can be recycled in a closed loop cycle. Using recyclable plastic as a starting material for production of new plastic items generally saves energy, but the recycling process is long, labor and energy-intensive (see the video tour of EcoStar Recycling Facility in Fitchburg, Wis.).
The majority of plastic bottles in U.S. are made of polyethylene terephthalate and high-density polyethylene, and their recycle rate is the highest, above 30% for 2012. According to the Environmental Protection Agency:
Markets for some recycled plastic resins, such as PET and HDPE, are stable and even expanding in the United States. Currently, the U.S. has the capacity to be recycling plastics at a greater rate. The capacity to process post-consumer plastics and the market demand for recovered plastic resin exceeds the amount of post-consumer plastics recovered from the waste stream. The primary market for recycled PET bottles continues to be fiber for carpet and textiles, while the primary market for recycled HDPE is bottles. … [N]ew end uses for recycled PET bottles might include coating for corrugated paper and other natural fibers to make waterproof products like shipping containers. PET can even be recycled into clothing, such as fleece jackets. Recovered HDPE can be manufactured into recycled-content landscape and garden products, such as lawn chairs and garden edging.
While recycling of polyvinyl chloride (#3, pipes, fencing), low-density polyethylene (#4, plastic bags) and polypropylene (#5, minority of plastic bottles, food containers) is also done to a smaller extent, polystyrene (#6), especially the expanded polystyrene commonly known as Styrofoam, presents a problem.
Styrofoam food containers are already banned in many cities around the world. In the U.S., the ban started in Portland, Ore., in 1990 and now has been adopted in more than 100 cities. Now the possible ban on Styrofoam is discussed in New York, Philadelphia, and Boston.
Although expanded polystyrene is recyclable, it is not a closed-loop cycle, that is, recycled Styrofoam cups are not remade into cups, but into photo frames (how many of those do we need?) or packaging material. Styrofoam is also one of the biggest component of ocean pollution and it is practically nondegradable. But most importantly, it is toxic to humans.
According to an OliveGreenMarketing.com report, the migration of styrene (the building block of polystyrene polymer) from food packaging into human tissues was first documented in 1970s, and by 1980 it was present in 100% of fat human tissue samples in the U.S. A polystyrene cup can “leak” up to 0.025% of it’s weight into a drink. Because styrene is fat-soluble, foods and drinks containing fat will extract more styrene out of the container; the same is true for hot or acid foods.
Styrene is recognized by EPA as a toxic agent: “Chronic (long-term) exposure to styrene in humans results in effects on the central nervous system (CNS), such as headache, fatigue, weakness, and depression, CNS dysfunction, hearing loss, and peripheral neuropathy.” It is a known endocrine disruptor and considered a possible carcinogen by WHO.
Why are we still using it? Simple: it is cheap. A big city like New York creates tens of thousands tons of Styrofoam waste per year, with the biggest polystyrene cup users being McDonald’s and Dunkin’ Donuts. A majority of public schools in Chicago (400,000 students) use Styrofoam containers. Can we afford not to ban it?
People in different countries can learn from each other how to encourage consumers to reuse and recycle. For example, in Monoprix supermarkets in Limoges, France, a customer must buy reusable, thick plastic bags or nylon fabric bags to carry groceries — there are no free, thin plastic bags at the checkout). In Beijing, plastic bottles recycling is credited to rechargeable subway cards right at busy subway stations. Or maybe we should follow a Dutch designer,Dave Hakkens, who shared a prototype for a plastics recycling machine, which can put recycling straight into the hands of people, right where they live.
Source: Plastic bottle recycling tops 30 percent in 2012, packagingdigest.com, November 6, 2013
Source: Bans across the US. nofoamchicago.org, November 26, 2013
Source: OliveGreen Marketing – Styrofoam, The Silent Killer, olivegreen.com.sg
Source: Styrene Hazard Summary, epa.gov, January 2000
Source: Paying With Plastic: Recycling Earns Public Transit Fares in China, ecowatch.com, August 5, 2013
Source: “Start a Recycling Centre” with Dave Hakkens’ Precious Plastic Factory, dezeen.com, November 11, 2013
Image by Mary Anne Enriquez
Video EcoStar Recycling Facility Tour, youtube