Oxo-biodegradable plastic makes environmental and economic sense

Many of us have mixed emotions when it comes to plastic. We love the fact that it is so versatile, in fact, there is nothing quite as strong and flexible for carrying shopping and protecting our food, water and other goods from damage and contamination, but we hate the fact that it can lie or float around for decades in the environment, blocking watercourses and endangering wildlife.

28 Aug 2015 | By Michael Laurier

The good news is that there is a new technology which allows us to keep the plastic, without the environmental nuisance associated with it. Oxo-biodegradable plastic performs exactly the same function as conventional plastic but will not remain a nuisance for decades.  This technology converts the plastic at the end of its useful life into a material that is biodegradable in the open environment (not just in compost) in much the same way as a leaf, but in a much shorter timescale, leaving nothing behind, no toxic residues and no fragments of plastic.
 
Unfortunately, the most common response to solving the problem of plastic waste is to ban plastic products. This is definitely the wrong way to go about tackling the problem, and it is environmentally and economically flawed.  
 
As yet there is nothing to replace plastic in terms of strength and flexibility, plastic is much too useful to be banned.  Plastic bags are often re-used around the home as waste bin liners or garbage sacks.  When bags are banned, the sale of plastic bin liners increases.  Paper bags disintegrate when wet and are not nearly as strong as plastic, and long-life bags can harbour germs, including Salmonella and E-coli as they are very rarely washed.
 
Life-cycle assessments have shown that the environmental credentials of bio-based plastic bags, paper, cotton and jute bags are not as good as oxo-biodegradable plastic. Bio-based plastic costs four times as much as oxo-biodegradable plastic to produce and unlike oxo-biodegradable plastic it cannot be made in existing factories with the existing workforce. Nor can it be recycled along with conventional plastic in a post-consumer waste stream, which means expensive segregation. Worse still, it biodegrades only in industrial composting and does not actually turn into compost as it converts rapidly to CO2 gas. 
 
Oxo-biodegradable plastic can be programmed at manufacture to have a specific service life (typically 6 to 24 months).  If collected during this time, it can be recycled with conventional plastic.  If it find its way to landfill it is chemically inert which means that unlike bio-based plastic it will not create leachate nor methane, which is a powerful greenhouse gas, and crucially if it does escape collection and end up in the open environment, it will degrade and biodegrade until it becomes food for micro-organisms, on land or sea, leaving nothing behind.  
 
At the moment oxo-biodegradable plastic is used mainly for lightweight shopping bags, food wrappers and packaging films, but there is growing interest from farmers for plastic sheeting to protect fruit, wrap silage, inhibit weeds and conserve moisture.  The fact that the life of the product can be pre-determined at manufacture makes oxo-biodegradable plastic uniquely suitable for these applications as the farmer no longer needs to remove or dispose of tonnes of contaminated plastic after the harvest.
 
At present, the Bureau of Indian Standards does not have a standard for oxo-biodegradable plastic, but there is no need for them to develop a standard when other countries are already using  the American ASTM D6954, the British Standard BS8472 and the French Accord ACT81-505.
 
In fact 11 countries in Africa, Asia and the Middle East have legislated on the basis of these standards to make oxo-biodegradable plastic compulsory and the Indian states could do the same if they are serious about tackling plastic waste and protecting the environment for future generations.
 
Michael Laurier is the CEO of Symphony Environmental Technologies Plc