What is the difference between decompose and biodegrade

Anything biodegradable will break down quickly and safely into mostly harmless compounds. But what makes a substance biodegradable? Anything that is plant-based, animal-based or natural mineral-based product is usually biodegradable.

According to the American Society for Testing and Materials ASTM biodegradables are anything that undergoes degradation resulting from the action of naturally occurring microorganisms such as bacteria, fungi, and algae. Although quickly is not defined biodegradable products are broken in way less time than non-biodegradable products like plastic for instance. Biodegradable objects can be much more than plants, as most people assume. Compostable means that a product is capable of breaking down into natural elements in a compost environment.

The breakdown process usually takes about 90 days. The ASTM defines compostables as anything that undergoes degradation by biological processes during composting to yield CO2, water, inorganic compounds and biomass at a rate consistent with other compostable materials and leaves no visible, distinguishable or toxic residue.

Producer claim that his product or packaging is biodegradable. Here are the following options:. Originally, compostability referred to the ability to initiate a process that lead to the creation of compost, while biodegradability referred to the ability to degrade through a biological process.

The difference between the two is that bio-degradation is a naturally-occurring process while composting is human-driven. Composting is an accelerated biodegradation process due to optimized circumstances. Composting includes human management, while biodegradation does not exclude it. Methane is created during anaerobic composting. It is 26 times more potent than carbon dioxide as a greenhouse gas and is a significant contributor to global greenhouse gas emissions.

The aerobic process of composting does not produce methane because methane-producing microbes are not active in the presence of oxygen. Both words are often used as synonyms but do not mean exactly the same. However, legal definitions exist for compostability.

In other words, plastic packaging must fulfil following rules to be accepted for industrial composting. Basically, the legislation defines under what conditions, at what speed and what the composition of the compost must be.

Skip to content Search for: Search Close. Close Menu. Etymologically Speaking What is Compostability? So, if there is no CO 2 production for plastic in respirometry tests, where does the year estimate come from? Although polyethylene bags don't biodegrade, they do photodegrade. When exposed to ultraviolet radiation from sunlight, polyethylene's polymer chains become brittle and start to crack.

This suggests that plastic bags will eventually fragment into microscopic granules. Scientists do know that many plastic break down into microplastics, as of yet, however, scientists aren't sure how many centuries it takes for plastics to completely break down and 'disappear'.

That's why some people give a year estimate, while others prefer a more conservative year lifespan. Explore the science ideas and concepts around biodegradability and bioindicators. Bioplastics are a form of plastic that can be made from renewable bio-based resources. Discover more about the difference in meaning between biodegradable and compostable. This article has lots of links to Science Learning Hub resources for primary teachers related to the recycling and biodegradability in the Material World strand of the New Zealand Curriculum.

Information to relevant articles, activities and media are grouped under the following headings:. In this Biodegradability experiment students set up an experiment to determine the biodegradability of different substances.

Find out more about backyard composting on this website. Single-use plastic shopping bags have been banned in New Zealand from 1 July