Saving the environment by banning plastic bags?
What is the influence of the 2016 ban on free plastic bags on the environment? Industrial ecologist Stefano Cucurachi received a LUF grant of €75.000 to answer this question.
170 bags per person
Although plastic bags are probably not the biggest contributor to the plastic soup, they arguably have gained the most media attention. And the amount of free plastic bags used is staggering. ‘Before the ban, we used 170 disposable plastic bags per person in the Netherlands each year’, says Cucurachi. ‘I want to find out what the impact of the ban is on the environment.’ His research will focus on the Netherlands, but the results can be applied to other countries. ‘More countries have been banning free plastic bags. My research could give them valuable information on what waste management systems are likely to work’, Cucurachi says.
'Plastic bags are a tricky type of waste. They are horrible to handle after usage. In sorting facilities, they get stuck in the systems, they block the sensors, or they fly away. On the other hand, for consumers they are great: flexible, usually durable, and cheap.'
A challenging task
Quantifying the impact of the ban on the environment won’t be easy, Cucurachi states. ‘I have to find out what the fate was of plastic bags before and after the ban. But data on waste flows of plastic bags is scarce, and in the little data that is available, plastic bags are often put together with other types of plastics. That makes it difficult to pin-point which streams went to recycling, how much was incinerated, and how much ended up in the ocean.’
Follow the plastic
Cucurachi will have to get creative with data sources. ‘You have all these different plastic waste streams, which are somewhat documented on a national and European level. But how do you fill the data gaps? How to understand how plastic bags ended up where they are?’ To answer these questions, Cucurachi will use an analytical method called Material Flow Analysis. ‘This method allows you to track the stocks and flows of materials across an economy: how many plastic bags were sold where, and were they imported or produced locally? Did these bags end up in an incineration plant, or in a recycling stream to make new products? How many likely found their way to the sea?’
After tracking the flow of plastic bags, Cucurachi will quantify the environmental impact of the bags with a method called Life Cycle Assessment. ‘It allows us to quantify the environmental impacts of products across their full life cycle. So think of the extraction of raw materials for the production – oils in this case, electricity and materials used in the manufacturing process, and even the fuel the trucks use to transport the bags’, he explains. He can then relate these products and materials to their environmental impacts. ‘Such as the greenhouse gas emissions, water usage, and the impact on biodiversity. This will be valuable information for policy-makers.’
Cucurachi adds that his role is to try and measure impacts, and identify where things do go wrong in the waste management system. But he warns: ‘It’s good to keep in mind that solving the problem of plastic pollution, and plastic bags, is also a matter of political choice and consumer behavior.’
Once a year the LUF Committee for Academic Expenditure (CWB) awards grants for scientific projects of Leiden University researchers. These grants for academic talent are often an important step towards grants by NWO and other institutions.