Recently I have come to aware of the issue of Great Pacific Garbage Patch from the media. It is large region in the Pacific Ocean that has accumulated much man-made garbage carried there by ocean current. Amount them are many plastic trash. On one hand plastic are very durable because they are not biodegradable. On the other hand plastic are photodegradable, meaning under the exposure of sunlight, they will slowly break down into smaller and smaller pieces. The result is a high concentration of pollutant in the water that is nearly impossible to clean up.
To most people this problem is nothing more than just a scientific interest. After all we don't venture into the middle of the ocean. So this problem is out of sight, out of mind. But today I have personally experienced the effect of photodegradation right in my own backyard.
Two years ago my mother has spent several months in my home. In her spare time she has built a vegetable garden in the yard. Being, shall I say, a resourceful person, she has reused many trash items to build a trellis. For example she scavenged many plastic bags that we would have throw away and used it as ties to the stakes.
Unfortunately, after she has left, we have not given the garden proper upkeep. It was quickly overrun by weeds. And finally I have to clear it out. As I was dismantling the trellis, I found the plastic bags have become very flaky. After exposed in sunlight for 2 years, the have all photodegraded. As I tried to remove them, they just break down into small pieces of white plastic and scattered all over the garden. There is just no way for me to mop up these tiny pieces from the soil. Who would have thought plastic bags can turn into a much bigger headache after it has degraded like this.