the recycling of cardboard boxes helps to keep them clear of bacterial contamination, a study has found.commissioned by the us organisation corrugated packaging alliance, and carried out by university of california davis and haley & aldrich, the study found that 100 of boxes tested met acceptable levels of bacteria for food packaging.with no guidelines on packaging bacteria levels existing from the us food and drug administration, a 1000 colony forming units per swab threshold was used by the study that had been developed by the university of guelph, food safety authority of ireland, and the new south wales food authority.secondary commodity markets 2015 the conference for buyers and sellers of recyclable materials takes place on 3 march 2015 in london. find out more herethe study of 720 swab samples taken from six corrugated box manufacturers in the us found that all met this threshold and that recycling had played a part in reducing bacteria levels because boxes were only used once.corrugated packaging alliance executive director dennis colley said &ldquothe singleuse approach for corrugated containers minimises the potential for contamination. after they are used, corrugated containers are returned to the paper mill for recycling. the recycling process greatly reduces bacterial loading.&rdquo 
