Project cost ($):
1 hour to prepare, 31 days for the science project experiment
Basic safety requirements
Table of Contents
This science fair project was done to evaluate the rate of decomposition of bio-degradable plastic in the natural environment. Biodegradable spoons are supposed to decompose with time, but exactly how soon does this process take place? The experiment involved using disposable spoons made from corn starch, wheat and plastic. These spoons were planted in soil.
Bio-degradable spoons lose some of their weight as quickly as within 30 days after being kept in soil
Biodegradable, decomposition, microorganisms, metabolize, composting, greenhouse gas
The materials required for this science fair project:
1. For this science fair project, the independent variable is the type of spoon used ? corn starch based, wheat based and plastic. The dependent variable is the amount of decomposition observed after 30 days. This is determined by using the digital weighing scale to measure the weight of the spoons before and after the 30 days. The constants (control variables) are the type of soil used, the length of time allowed for decomposition, the temperature and humidity.
The results showed that the weight of the corn starch based spoon and wheat based spoon had reduced after 30 days in the soil but the weight of the plastic spoon remained the same.
The chart below represents the results of our science project experiment.
The hypothesis that biodegradable spoons lose some of their weight after as little 4 weeks in the soil, is proven to be correct. At 30 days, it was evident that the corn starch-based spoons and the wheat-based spoons had begun to decompose, but this was not the case for the plastic spoons.
More than 20 million tons of plastic materials are produced around the globe every year. Out of these, only a small percentage are recycled. The difficulty faced in the recycling of plastic material is that most plastic waste matter comes mixed together with other types organic wastes. The process of separating the plastic from organic waste is time consuming and costly. However, in the case of bio-degradable plastics, the presence of organic waste actually aids the process of decomposition! Bio-degradable plastics may be a good alternative to regular plastic, in order to prevent the pollution of our environment.
Try to repeat this science fair project, this time, evaluating different environments for decomposition, such as by immersing the plastic in lake water or vegetable oil.
You could also try repeating the science project with other types or brands of biodegradable spoons, or by introducing specific species of bacteria into the soil.
Biodegradable plastic - http://en.wikipedia.org/wiki/Biodegradable_plastic