6/29/2007

How long it takes for plastic bag to decompose ?

For everyday consumers, plastic shopping bag are cheap and easy to use, but ugly to look at when they stuck on tall trees or being littered to the street. I still remember a local news (of late 80's) profiling a young business star; he was on the news because the big profits earned from the plastic bag plant he owned. There is a social revolt going on lately to stop people using traditional plastic shopping bag due to enviromental concerns. Some want to make it "as fashionable to carry plastic as it is to wear fur", others simply baned them.
The most common type of plastic shopping bag is made of polyethylene, a man-made polymer that microorganisms don't recognize as food. In another word, they are not biodegradable like newspaper and banana peel
However, plastic bag do photodegrade. When exposed to ultraviolet radiation from sunlight, polyethylene's polymer chains become brittle and start to crack, and plastic bags will eventually fragment into microscopic granules. As of yet, however, scientists aren't sure how many centuries it takes for the sun to work its magic due to many variables. That's why certain news sources cite a 500-year estimate while others prefer a more conservative 1,000-year lifespan. It feels like these figures are just another way of saying "a really, really long time."
For me, the quickest way to solve the problem is to develop plastic bags sensitive to photodegradation and biodegradation. Consumer are willing to spend a bit more money on these new bags, instead of stop using them.

2 comments:

Debo Hobo said...

Exactly, If we don't handle up on our polution now we are in serious trouble.

Anonymous said...

Some stores (e.g., Ikea) now charge customers for plastic bags...hit folks 'where it hurts' and MAYBE they'll change. As always, there is the option of cloth bags. :)