1: Corn
Corn plastic containers are more environmentally friendly than traditional petroleum-based plastics.
Polylactides (PLA) are plant-based, usually corn, plastics that have an edge over the real thing: They decompose within 47 days, won't emit toxic fumes when burned and manufacturing them uses 20 to 50 percent less fossil fuels than petroleum-based plastic .
Corn-based plastics can be used to manufacture food storage containers as well as storage for consumer goods. If Walmart used 114 million PLA containers a year, company executives estimate they could save 800,000 barrels of oil every year . Cornstarch bags could replace petroleum-based plastic bags and decompose in the landfill or in your compost pile.
While the theory is that PLA is carbon-neutral because it's derived from renewable plant starches, the reality right now may not necessarily be a perfect solution. PLA is often made from genetically modified corn, the growing of which raises environmental, human-health and economic concerns, and the end result may take longer than estimated to decompose.
2: ECM BioFilm
"Biodegradable" and "plastics" might not seem like two words that should go together, but ECM BioFilms Inc. has developed a technology that makes it so. Accidentally, at that. While experimenting with dyes and scent additives in plastic fishing lures, ECM discovered some lures were decaying.
While not a substitute for plastic, using ECM's additive as an ingredient (like adding dye to the mix) in polyolefin packaging and products renders those products biodegradable. Plastic manufactured with this additive is not sensitive to heat or light degradation, which gives it a long shelf life. It will, however, completely biodegrade into soil -- whether that's the landfill, your compost pile or the side of the road -- between 9 months and 5 years.
With this technology, single-use plastics such as disposable diapers, trash bags and food containers could be a little more environmentally friendly by not sitting in landfills for hundreds of years. The technology is still a work in progress: Additives for items such as electronics casings, toys and car parts aren't yet on the market.
3: Liquid Wood
Liquid wood is made from a byproduct of paper mills.
Liquid wood is a promising new bioplastic, or biopolymer. Biopolymers fake it; these are materials that look, feel and act just like plastic but unlike petroleum-based plastic, they're biodegradable. In this case, liquid wood is made from pulp-based lignin, a renewable resource. To make biopolymers, lignin, a byproduct of paper mills, is mixed with water and exposed to high temperatures and high pressure to create a moldable composite material that's strong and nontoxic, making it a good plastic substitute. German researchers have used it to manufacture a variety of items including toys, golf tees and even hi-fi speaker boxes.
Because it's made of wood, it can be recycled as wood, either broken into pieces and used as filler or burned.
4: PHB Biocomposites
Plastic wouldn't be so bad if it was renewable and not made of global-warming-contributor petroleum, right? Well, that's a tall order. However, a material made from bacteria shows potential as an emerging new "green," biodegradable plastic. The material is a modified form of polyhydroxybutyrate (PHB), which is an energy and carbon source created by the natural biological fermentation process of many species of bacteria. Need more PHB? Feed sugar to certain types of bacteria and wait.
What makes this material special is that while it's created by bacteria, it closely resembles man-made polypropylene. It is completely biodegradable without leaving behind residue. While it's still less flexible than petroleum-based plastics, it can be used in packaging, agriculture and biomedical products.
5: Glass
Glass isn't made from fossil fuels -- it's made from sand.
Once upon a time, both moms and milkmen filled glass bottles with milk. Look around your kitchen (or just open your refrigerator) and you'll probably see a lot of plastics -- water bottles, soda bottles, food storage containers. Times have changed.
While we can't seem to live without plastic, it may actually be that we can't live with it: Studies question whether some chemicals in plastics may disrupt the body's endocrine system, causing hormonal, developmental and reproductive problems. Often plastics contain bisphenol A (BPA) or phthalates. BPA helps make plastic shatterproof (and is used in products such as baby bottles and compact discs), whereas phthalates make plastics more durable and more flexible (and are commonly found in products including plastic storage containers and toys).
Unlike plastic, which is made from fossil fuels, glass is made from sand. Not only is sand a renewable resource, it doesn't contain chemicals that can leach into your food or body, and it's easily recycled -- whether you throw bottles in your recycling bin to be turned into new bottles or reuse glass jars for storing leftovers. While it may break if dropped, at least glass won't melt in your microwave.
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