- Toddler and baby foods sampled were free of food packaging chemicals.
- MPI consider “there is a negligible food safety risk” from chemicals in food packaging leaching into food.
- Pizza and corn chips contained levels of phthalates above Specific Migration Levels
With so much food being “ready to eat” there is a large amount of food packaging which has been created to transport this food – from plastics to cardboard to organic materials but do the chemicals within the packaging leak into the food? The New Zealand Ministry of Primary Industries (MPI) undertook a study to look at this question . The primary objective was to identify any dietary risk from the migration of packaging chemicals into New Zealand foods.
What are phthalates?
Phthalates are a group of chemicals used in the manufacture of plastic products. They are a colourless and odourless chemical applied to increase the transparency, durability, flexibility and longevity of plastics products. There are associations with phthalates affecting the metabolism, hormones and neurological systems of humans.
What did MPI do?
Sixteen of the 74 samples contained three phthalates moieties and 11 samples3 contained five printing inks/photoinitiators contaminants.
Only two samples contained phthalates at a level higher than a Specific Migration Limit (SML) as set out in the European Union regulation (EU No 10/2011). These were one (out of two) sample of corn chips in a plastic/foil bag and one (out of five) sample of pizza in a cardboard box. The DEHP found in the corn chips was nearly three times the SML (4.4 mg/kg where 1.5 mg/kg is the SML) and the DEHA found in pizza was one and a half times the SML (27 mg/kg where 18 mg/kg is the SML).
No samples of the printing inks/photoinitiators were greater than the recommended levels4.
To make the results more meaningful …
MPI applied all affected food items to a diet scenario to calculate how much of each substance would be eaten in a regular diet. A conservative approach was taken and the dietary scenario applied the highest concentration of contaminant found in a food e.g. the diet scenario had the pizza level of DEHA at 27 mg/kg even though only one sample in five contained DEHA.
From the diet scenario …
The ingested levels of printing inks/photoinitiators were below a health-based guidance value for all of the population but not the phthalates.
While the ingested phthalate levels were below a health-based guidance value for an adult, it was not always the case for teenagers, children and toddlers who are smaller. MPI concluded, “there is a negligible food safety risk” as the worst-case dietary scenario was used to calculate that risk e.g. very high pizza consumption over a lifetime. Yes, and this might be so in a normal dietary situation but is there “risk” in an extreme scenario of young children with a diet high in the ‘particular’ corn chips or the ‘particular’ pizza with high levels of phthalates?
The identities of the food products were not provided but here is a list of the 74 food samples tested. The foods with no chemical migration have been highlighted in green.
If you are concerned about chemical migration …
- Use the right plastic for the job and follow the manufacturer’s instructions
- Heat changes plastic wrap, so avoid cling film touching food during cooking
- Defrost meat wrapped in plastic or on plastic trays at low temperatures.
- Avoid dented food or drink cans
- Don’t heat food in supermarket bags
- Use supermarket bags with the printing on the outside
Ministry of Primary Industries. Occurrence and risk characterisation of packaging chemicals in New Zealand foods. MPI Technical Paper No: 2017/61. Wellington: Ministry of Primary Industries, 2017.
- Ministry of Primary Industries. Internet: https://www.mpi.govt.nz/food-safety/whats-in-our-food/chemicals-and-food/plastic-packaging/ (accessed 9 Jan 18).
 Chromatography separates the chemical molecules
 Mass Spectrometry identifies and quantifies the chemical molecules
 1 DETX, 5 BP, 1 HMPP, 1 IR184, 1 BP and IR184, 1 HMPP and IR184, 1 BP, DMPAP and IR184
 Recommended levels: one of the five printing inks/photo initiators detected had an EU SML, for the remaining four a threshold of toxicological concern approach was adopted to assess the risk.