Recycling contamination: Understanding it and preventing it

Recycling contamination, when materials are sorted into the wrong recycling container or not properly cleaned before finding their way into the waste stream, not only causes risks in terms of Health & Safety but often leads to increased costs associated with poorer quality end product and a reduction in the overall amount of material that that can be recycled.

Join WRAP's webinar - Tackling Contamination in Dry Recycling; a Case Study

Though many local authorities are doing all they can to tackle contamination on a local level, there is limited evidence that their efforts work, in large part because approaches vary, they happen somewhat ad-hoc, and projects are set up in such a way as to make monitoring and evaluation difficult.

Add to this the challenges of communicating with residents and businesses in a practical, relatable way - acceptable levels of contamination are subjective and guidelines can be inconsistently applied - and we begin to understand how preventing contamination, whilst entirely possible, isn’t necessarily all that straightforward. For example, though the term ‘contamination’ is used widely by those of us working in the sector it is not a term that householders really use or understand.

So, what are the biggest barriers to reducing contamination and how do we start to knock them down? Research carried out by WRAP in 2020 reviewed existing evidence on contamination and led to a small qualitative assessment, providing for the first time some real insight into people’s behaviours when it comes to contamination.

As you might expect, recycling is something more and more householders are doing. At the same time contamination is widespread and on the rise. In fact, our research reveals that 82% of UK households add one or more items to their recycling collection that are not accepted locally.

Interestingly, the more problematic forms of contamination aren’t necessarily the most common, but when contamination does occur it is most often associated with the householder not recalling communications around the recycling collection scheme in their area. In addition, people who tend to contaminate their recycling containers are more likely to have children in the home.

This is where the research can really help us get to the root of the problem. For example, our study indicates that people tend to contaminate due to three considerations; individual – one’s own understanding, circumstantial - factors tending to be outside one’s own control, and item based.

Whilst the circumstantial and item based reasons play a part on some occasions the individual tendencies are always present and therefore factors such as lack of knowledge, optimistic recycling, following what seem like logical but incorrect rules of thumb, and making inconsistent snap decisions about whether or not something is recyclable are key causes of contamination.

We also know that there are, broadly speaking, two distinct behaviours when it comes to recycling. Those who, even when they are sure an item can be recycled check anyway. And those who, despite best intentions, are inclined to guess if what they’re throwing in the recycling bin can in fact be recycled. Both groups can of course contaminate, though it is this second group, more often than not, that do.

For that reason, when it comes to developing interventions that tackle contamination, frequent checking is the most effective behaviour to promote. Lastly, understanding that there are reasons people guess; so it’s about making guessing more successful through communications that focus on specific contaminants and the consequences of contamination when it happens. Giving people positive feedback and practical information should they make a mistake can help to reinforce understanding.

To this end, WRAP has developed a range of tools, guidance and communication resources specifically for Local Authorities. Including the Tackling Contamination Guidance which provides an update for Local Authorities still facing regular problems with the quality of the materials collected, on ways to tackle contamination. As with all of the resources we create, it is free to download and can help you develop policies, practices and communications that are effective in tackling contamination.

For more information on WRAP research watch the recording of our recent webinar and see the results of our work with the Re3 Waste Management Partnership on contamination register for our webinar on Thursday 15 July at 09.30.