The article discusses how forests used for making cartons can store carbon, helping reduce greenhouse gas emissions. The researchers developed a way to measure the carbon footprint of cartons in Europe. They looked at the emissions from making cartons from new and recycled materials and printing them. The average carbon footprint of cartons sold in Europe was then calculated. The study also considered how the cartons are disposed of at the end of their life. The findings show the total greenhouse gas emissions for making and using one tonne of cartons in Europe.