Paracelsus' poison

Paracelsus' poison

Good news, we are not at risk from our food packaging

For most of us, food is more than fuel, it is a source of delight and an important part of healthy living. Also for most of us, our food must travel substantial distances from producer to our plate, with many opportunities for the foodstuff to be contaminated with extraneous substances like bacteria.

Like it or not, food packaging is an important part of food safety. Proper food packaging prevents foods being contaminated during transport storage and sale, as well as improving their shelf life. Ironically, in this modern age we are often more concerned about the packaging that shields our food from these contaminants than the contaminants themselves. However, a new study has confirmed that the health risks from packaging are minuscule.

Why is there concern? The very clever, modern materials that shield our food from contamination may contain chemicals that could migrate into these foods to levels that could potentially affect our health. Some of these materials, including bisphenol A (BPA) and phthalates, mimic the effects of our bodies’ endocrine hormones and could possibly affect the endocrine system at low levels.

Food Standards Australia New Zealand is the regulatory body in charge of food safety. It routinely surveys foods to ensure exposure to health risks from food contamination is low to negligible. The recently released study looks at chemicals that can migrate into foods from packaging, following up a previous survey in 2010.

81 typical foods were tested for levels of 30 chemicals (BPA, epoxidised soybean oil, di-2-ethylhexyl adipate (DEHA), two perfluorinated compounds, 14 phthalates, and 11 chemicals used in printing inks).

The good news is that half of the 30 chemicals tested for were not detected at all by sensitive analytical techniques. Of the 15 remaining chemicals, very few foods had detectable levels of these chemicals, and all but two of those that did fell well below the accepted international Tolerable Daily Intake (TDI) levels.

TDI levels are set on the basis of a wide variety of information about exposure, but typically the levels are set to 100 times lower than the amount that produces no effects in animals that have been fed the substance for over 80% of that animals lifetime.

The compounds that had levels below the acceptable TDI levels included Bisphenol A, which has been the focus of recent public concern. For Bisphenol A, only eight of the tested food had detectable levels. To give an idea of how little risk there is, you would need to consume over 100 Kg of the baked beans with the highest levels of BPA a day, every day, to reach the TDI threshold.

These results are consistent with the findings of the 2010 survey.

Two exceptions were the phthalates di(2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DINP), which were found at higher that recommended levels in a very few foods, and further studies will be undertaken as well as consultation with industry to ensure reduced levels.

Even so, the risks from these two phthalates are low. In the case of DINP, out of 48 foods tested, high levels were found in a single sample of peanut butter, four hamburgers and one pizza. You would need to consume 200 grams of that peanut butter or 0.6kg of that pizza daily to exceed the tolerable daily intake level. While this is possible, it is very unlikely[1]. Nonetheless these findings will be followed up to see why these samples had high levels, and to reduce the levels in future.

Overall, despite some headlines, the study again confirms that our foods are generally safe, and we do very well by international standards.


Update 23-01-2016: In response to an emailed comment I weighed large pizzas from one of our local take-aways. A single large weighed 0.6 kg. Yes, it is possible for some people to consume a large pizza by themselves (I can do that when hungry). But to do that daily for weeks on end, or a large proportion of your lifetime is unlikely.

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