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Participant Information and Consent

Please take the time to read the following information. If you have any further queries, please contact at UCL's Plastic Waste Innovation Hub.

Invitation to participate

The Big Compost Experiment is a nationwide research project about the role and effectiveness of compostable and biodegradable packaging. It is one of the research initiatives of UCL’s Plastic Waste Innovation Hub, an 18-month interdisciplinary research project (funded by UKRI and EPSRC) aimed at developing new ways of designing out plastic waste. It comprises a short online survey of your opinions on compostable and biodegradable packaging, and how you process food waste. There is also an optional home composting experiment for those who wish to participate further.

Project aims

This study is for everyone, whether you compost or not. By taking part in this study, you will be helping us to determine the viability of biodegradable and compostable plastics. The data we collect from you will feed into our Live Composting Map, a live map of home-composting activities across the UK, and, with your consent, we will keep you up-to-date with the project as it develops. However, you also have the option to remain anonymous; we won’t need to bother you again.

Taking part

Your participation is entirely voluntary and confidential. You will be notified and given the option to consent before submitting any personal information. The first part of the experiment is a short survey: We would like to know what you think of biodegradable plastics, what you do with them, and if you ever compost them yourself. If you do engage in composting, then there is a second part to the experiment. We ask if you would place a few biodegradable plastic items in your compost under controlled conditions, and then report back on whether they compost or not. For further information see our Experiment Guidelines.

Information handling

The lawful basis for processing your personal data will be for the ‘performance of a task in the public interest’. Request for personal information is kept to a minimum and is anonymised, which means that your responses will not be identifiable. Your personal data will be kept strictly confidential and will only be processed by the research team for the purposes of this study. We will minimise the processing of your personal data wherever possible. UCL Data Protection provides an oversight of UCL's activities involving the processing of personal data. If you are concerned about how your personal data is being processed, or wish to withdraw your information from this project, please contact UCL Data Protection in the first instance at For further information see our Privacy Notice.


You have the option to share photographs of your home composter and your chosen biodegradable and compostable item(s). You can also choose to post them anonymously on our Gallery page, in order to help us promote composting across the UK. Any images will only be displayed with your consent. For more information see our Photography Guidelines.

What will happen to the results?

The results of this project will be shared with policymakers and manufacturers, as well as other interest groups concerned with plastic waste. Your responses will be anonymised, so you will not be personally identifiable in any presentations, reports, or publications. We would also like to keep you updated about the progress of the project, which we will do through our Blog on the Big Compost Experiment and UCL's Plastic Waste Innovation Hub websites. A summary of the results will be made available in 2020.

Health and safety

The home composting experiment involves digging or handling food waste and compost. People with allergies should seek advice first before participating. Under 18s should be supervised by a responsible adult.

Further questions?

If you have any other questions, please contact Danielle at UCL's Plastic Waste Innovation Hub at

Concerns or complaints?

If you have any concerns or complaints about this study, please contact Danielle at UCL's Plastic Waste Innovation Hub at, or the Chair of UCL's Research Ethics Committee at

Further information

The Big Compost Experiment was conceived by Danielle Purkiss and Professor Mark Miodownik from UCL’s Plastic Waste Innovation Hub. The test and images were created by Danielle Purkiss, food photography by Studio-SP, and the website was designed by Ten4.

This is one of a series of research initiatives currently being undertaken as part of UCL’s Plastic Waste Innovation Hub, jointly funded by UK Research and Innovation (UKRI) and the Engineering and Physical Sciences Research Council (EPSRC). The Hub brings together a multidisciplinary team of experts from across UCL, who are devising and testing new interventions in eliminating plastic waste.

Thanks for reading this, and for taking part in the Big Compost Experiment!

If you compost and want to take part in a home composting experiment, you’ll need:

  • a selection of identical compostable or biodegradable items (see list below)
  • a net bag and clip to securely close it (see guidance below)
  • a plastic milk bottle cap (or similar) and permanent marker pen to identify your items

If you do not use a composter but you're interested in finding out more, please see our Composting Processes page for more information.

1. Choose your experiment items

Select the type and quantity of compostable or biodegradable plastic items from our list that you would like to test. Please only select items that display the following manufacturer information:

  • 'compostable' (only)
  • 'home biodegradable'
  • 'home compostable'
  • 'suitable for home composting'
  • TUV OK Compost 'HOME' certification mark
  • Din Certco 'HOME COMPOSTABLE' certification mark

NOTE: If testing multiple items together please ensure they are an identical type and brand (one type and brand of item per net bag).

2. Prepare your experiment equipment

To make locating your experiment items in your compost easier, please compost your items in a plastic net bag (the kind of net bag used to hold fruit in a supermarket would be ideal). Use a permanent marker pen to identify your items on a plastic milk bottle cap (or similar) and add to your net bag. To test fruit and veg stickers please stick each label on a plastic milk bottle cap first then add to your net bag. Use a permanent marker pen to identify them. You will have the option to upload photographs of your composter and experiment equipment to help us analyse your results. See our Photography Guidelines for more information.

NOTE: Please ensure you use a perforated net bag. This is so a sufficient flow of oxygen, organic waste and microorganisms can come into contact with your experiment items.

3. Create a login account

Create a login account and share a few extra details about what composter you will be using for the experiment, its location in the UK for our Live Composting Map, and your composting method. Please set the duration of your experiment according to how long it usually takes you to make compost. There is the option to share photos of your composter and experiment items and equipment, if you wish. Please indicate on your form if you would like to share your images on the Big Compost Experiment website. See our Photography Guidelines for more information.

4. Start your experiment

Securely close the net bag containing your experiment items and identifying markers and add to your composter. Carry on composting as usual. We'll send you an email reminder when your experiment is due to finish and it's time to look for your net bag and items.

5. Submit your results

When your experiment timer has finished, please look for the net bag and items in your compost. You can use a trowel, spade or household sieve to locate it. Under 18s must be accompanied by a responsible adult. Check the contents of your net bag for any traces of your items. If there are any traces please compare them with our 'Scale of Degradation' in the results form in your login account and share any other useful observations about your experiment. There is the option to share a photo of your results. Please indicate on your form if you would like to share your image(s) on the Big Compost Experiment website. See our Photography Guidelines for more information.

NOTE: Once you have completed your experiment, please dispose of any item remains in your general waste collection. Check locally for recylability of other experiment equipment and rinse before recycling.

How to take a photograph of your experiment equipment

Pre- and post-composted items and equipment

  1. Place your biodegradable or compostable items on a clean surface alongside any secondary packaging (if applicable) and net bag. A contrasting surface is preferable (i.e. one on which the items will stand out).
  2. Orientate items and packaging (if applicable) in order to capture any compostable labelling or certification marks (if displayed). If testing multiple items together please ensure they are an identical type and brand (one type/brand of item per net bag).
  3. Position your camera approximately 1 metre above the objects. Position items clearly within the viewfinder of your camera or camera phone, so that all edges of items are visible. Please ensure no recognisable features (people, faces, house number, etc.) are visible in the image.
  4. Take a photograph (while keeping your hand steady!)
  5. Upload photographs via your login account, with the option to display them on our Gallery page.