Are you turning up the heat on plastic?

Microwaved meal by JIP licensed under Creative Commons

The UK consumes 79 million ready meals every single day with a market value of nearly £4bn. In the UK, 86 per cent of adults eat ready meals, and 3 in 10 eat ready meals at least once a week. If you have surveyed the range of ready meals in the freezers or in the chiller cabinets in the supermarket, what strikes you? Correct! That the vast majority are encased in plastic, and what do the majority of folks do but sling them in the microwave or in the oven, still in their plastic trays.

The material used for the trays is made of CPET (crystallised polyethylene terephthalate – try saying that after a couple glasses of Prosecco!) and polypropylene, because these plastics can withstand high heat. Some boast that the trays are recyclable; yes that’s helpful in reducing plastic waste, but how many actually end up in incineration or in landfill for centuries to come? What about the zillions of those thin plastic film lids floating about?

There are many health warnings about the ingredients in the foods themselves, e.g. too much fat and salt, but how many warnings do you find on the sleeve regarding the plastic trays? The words ‘microwave safe’ or ‘oven safe’ merely indicate that the receptacle will not fall apart in a gooey mess when heat is applied! Nowhere is it mentioned that heating plastic allows the chemicals in the plastic to leak out into the food. Chemicals which are known to be hormone disrupters. Multiply the number of ready meals an individual may consume over the course of a year, and the exposure to those chemicals (added to the chemicals in so many everyday plastic products) mounts up to a harmful effect on human health.

City to Sea and Natracare hosted a discussion panel: This Could Turn Toxic; it’s well worth a watch. One of the panellists, Dr Charlotte Lloyd, an environmental chemist, said:

“When we analyse plastic in the lab, one of the main methods we use is microwave extraction to get chemicals out … so don’t microwave food in plastic as the chemicals very readily leach out”.

That would include leftover takeaways, even home cooked and frozen meals! This is a scientist telling us that they take the plastic apart in the microwave to be able to analyse and identify the chemical additives.

So, if you want to have a ready meal, or rely on them for other reasons, always transfer the food to a china plate and cover with a china bowl, or to a Pyrex dish, before heating/cooking in the oven or microwave. Sound advice for us all!

(sources:, “This Could Turn Toxic”,, Cancer Research)