In a competitive marketplace, packaging has to efficiently protect food, while attracting customers, but there is an increasing focus on its sustainability credentials. Many claims are made, but Greiner Packaging UK & Ireland asks: 'How do you know the CO2e impact of your plastic packaging?’, and goes on to question how you can properly know what percentage of post-consumer waste a pack contains, will it be liable for the UK plastic packaging tax, and does it have EU food approval?