Is Your Takeaway Pizza Box Toxic?

A relaxed evening with a good film, a few beers and a pizza from the local takeaway — what could be better? Well several news reports could ruin your evening and this time it’s not the food police complaining about junk food — but toxic pizza boxes.

Those square cardboard boxes could be home to toxic substances according to both the Food and Drug Administration (FDA) in the US and a team of scientists from Denmark. Two different studies have highlighted possible problems with takeaway food boxes — so let’s take a look and find out what the researchers have found.

Keeping the grease at bay

There is nothing worse than carrying your pizza home and then finding that the grease and moisture from the hot food has transferred to the box — which suddenly collapses in a soggy mess. Packaging manufacturers use chemical coatings to stop this happening — and some of these chemicals belong in a group known as perfluoroalkyl ethers and the FDA is concerned.

On their website, they state:

The FDA is amending the food additive regulations to no longer provide for the use of three specific perfluoroalkyl ethyl containing food-contact substances (FCSs) as oil and water repellants for paper and paperboard for use in contact with aqueous and fatty foods because new data are available as to the toxicity of substances structurally similar to these compounds that demonstrate there is no longer a reasonable certainty of no harm from the food-contact use of these FCSs.

Perfluorinated compounds (PFCs) have been widely studied and links have been seen between PFCs and development in infants. Higher PFC levels were also found to be a factor in the time it took women to get pregnant and with irregular menstrual cycles. The ban was described as ‘a first step to improving food safety’ in one news report.

Recycling old boxes

Meanwhile, a study carried out by scientists in Denmark looked at contamination in recycled paper and board food contact materials — pizza boxes. In a paper published in Food Additives and Contaminants the researchers found that they could only identify 3% of the contaminants responsible for aryl hydrocarbon receptor (AhR) toxicity. AhR is a human protein that has roles in signalling and development.

The team prepared an extract from a pizza box by boiling it in ethanol and then tested the AhR toxicity of the extract in a cell assay. To separate the components in the extract, the team used HPLC — followed by analysis using GC-MS and UHPLC-MS which allowed the team to identify some of the compounds in the sample. Some of the deliberations when performing this type of analysis are covered in the article, Recent Advances in the Applications of Mass Spectrometry to Environmental Matrix Analysis.

The Danish scientists conclude that some toxic agents in recycled paper and board materials still have to be identified and recycled paper and board could contain compounds that shouldn’t be there.

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