By Karen Baker, Technical Analyst
Food packaging is having its moment in the press, with plastic packaging revealed as one of the main sources of packaging waste in Europe – 37 % of all food sold in the EU is wrapped in plastic. It has been found that such packaging, although designed to reduce food waste through extension of shelf life, can be more damaging to health and more difficult to dispose of than its original contents.
Breaking down packaging
There is a growing army of people who are trying to live life free of single-use plastics, through buying local produce to bypass packaging, to making use of reusable containers. However, there is a point where it becomes impossible to buy certain items without them being wrapped in plastic, so until manufacturers change it will continue to be challenging.
There is some light at the end of the tunnel in a very recent joint study from the Universities of Portsmouth and South Florida. A synthetic enzyme has been serendipitously created, re-engineering an active region of the PETase molecule to create a mutant enzyme with an enhanced ability to attack polyethylene terephthalate (PET), one of the most popular forms of plastic used in the food and drink industry. This enzyme is even better at degrading the plastic than the one that evolved in nature, and the researchers are working to further improve the enzyme to attack in a fraction of the time.
Health risks of leeching plastic
In terms of health risks, developing alternatives to plastics from the outset would be the safer option. Recent US research news adds fuel to the fire, with 40% higher toxic phthalate levels identified in people who mostly ate food purchased at restaurants, fast food outlets and cafeterias. Many products contain phthalates, particularly take away boxes, plastic containers and food handling equipment. Even more worryingly, milk packaged in glass that passes through plastic tubes on its way from the cow to the bottle has been found to take lipophilic di-2-ethylhexyl phthalate (DEHP) into the bottle and leech into the lipid-rich milk. Phthlates pose a substantial human health risk as hormone-disrupting chemicals, and cumulative exposure is a distressing issue.
The urgency to find a solution to plastic waste, whether it is Governments encouraging societies to reduce plastic usage in the first place, or research to engineer molecules to improve performance at breaking down plastics, is very real. Experts estimate that by 2050, there will be as much plastic waste in the ocean by mass as there are fish. It’s a global problem posing serious risks to humans wildlife, and reducing plastic and evaluating our waste situation should be a priority on the world agenda.
 Characterisation and engineering of a plastic-degrading aromatic polyesterase, Proceedings of the National Academy of Sciences, April 2018.
Dietary sources of cumulative phthalates exposure among the US general population in NHANES 2005-2014, Environment International, 2018.