Food packaging chemicals may be harmful to human health over long term

Synthetic chemicals used in the packaging, processing and storage of food might be harmful to human health over the long term, according to a new commentary in the Journal of Epidemiology and Community Health. 

The authors claim that tiny amounts of synthetic chemicals leak into food. While these minute quantities in themselves do no harm, no one knows how safe we are from a lifetime's exposure to the chemicals, such as formaldehyde, through eating food previously wrapped or stored in plastics. In a commentary piece in the journal the scientists note that some of the chemicals that could cause concern are regulated but this does not prevent their being used widely in food packaging. They say that people who eat packaged or processed foods are likely to be chronically exposed to low levels of these substances throughout their lives.

Consumers exposed to known toxicants
The writers, who include Jane Muncke, from the Food Packaging Forum Foundation, in Zurich, say there is cause for concern on several grounds. Chemicals known to be toxic, such as formaldehyde, a cancer causing substance, are legally used in these materials. Formaldehyde is widely present, albeit at low levels, in plastic fizzy drinks bottles and melamine tableware. Other chemicals known to disrupt hormone production and used in food and drink packaging, include bisphenol A, tributyltin, triclosan, and phthalates. Altogether, more than 4000 chemicals are involved. Nevertheless, chemicals used in the food manufacturing process are seldom listed on packaging labels. One reason is that foods come into contact with chemicals at all stages of the supply chain, including during storage, processing and packaging. But information on the chemicals used along the way "is not shared" in the food industry, Muncke said. Even organic milk sold in glass bottles may have come into contact with chemicals leeching from the tubes connected to machine-operated pumps, she said.

Doubts on the adequacy of chemical regulatory procedures
"Whereas the science for some of these substances is being debated and policy-makers struggle to satisfy the needs of stakeholders, consumers remain exposed to these chemicals daily, mostly unknowingly," authors write. They warn that potential cellular changes caused by food contact materials, and in particular, those with the capacity to disrupt hormones, are not even being considered in routine toxicology analysis. They suggest this "casts serious doubts on the adequacy of chemical regulatory procedures".

Gaps in knowledge need to be filled
It will not be easy to monitor and assess the effects over decades of exposure to these chemicals, scientists say. There are no large groups of people who are not exposed to wrapped and processed and stored food. Studies have shown that we all have traces of these chemicals in our bodies. That means it is not possible to carry out a study comparing people who have been exposed to them with people who have not. But a population-based assessment is urgently needed as well as bio monitoring to establish any potential links between food-contact chemicals and chronic conditions such as cancer, obesity, diabetes, and neurological and inflammatory disorders, particularly given the known role of environmental pollutants, they argue. "Since most foods are packaged, and the entire population is likely to be exposed, it is of utmost importance that gaps in knowledge are reliably and rapidly filled," they say.

How high is the risk
Critics, however, insist that the dangers of toxic chemicals in food contact materials are overblown.
Formaldehyde, a known carcinogen, maybe be found in plastic drinking bottles – but it is naturally present in certain foods as well.
"To consume as much formaldehyde as is present in a 100-gram apple, you would need to drink at least 20 litres of mineral water that had been stored in PET [polyethylene terephthalate] bottles. Obviously the concern about formaldehyde from food packaging is significantly overrated, unless we are willing to place ‘potential cancer hazard’ stickers on fresh fruit and vegetables," said Dr. Ian Musgrave, senior lecturer in the medicine faculty at the University of Adelaide.
But according to Muncke and colleagues, toxic chemicals in the food supply chain are so pervasive that consumers can do little to avoid them.

Ironically, products made by large corporations such as Coca-Cola and Nestle may be a relatively safe bet. Unlike smaller companies with fewer resources, these corporations have set up in-house labs to test for chemicals in their packaging and food products, Muncke said.
"They’re doing a good job," said Muncke, who described the testing measures as a form of enlightened self-interest. "It only takes one consumer organization to go and test their products and blow up in the media that their products contain [a toxic substance]" to hurt a corporation’s bottom line, she pointed out. Unfortunately, smaller food companies do not have the financial resources to test their products for trace amounts of chemicals, she said.

We can change some habits
Food-borne chemicals are a policy issue, and until regulators step in to require broader testing of chemicals that come in contact with food, consumers will have difficulty limiting their exposure to toxic chemicals in foods, she said.
Nevertheless, Muncke said her research has influenced her own habits. She tries to buy mainly fresh organic foods to cook at home; avoids packaged foods and plastic cutlery, drinking bottles and food containers; and uses glass or stainless steel containers for storing food.

Sources: http://esciencenews.com/, http://www.sciencedaily.com, http://www.medicalnewstoday.com/, http://www.theguardian.com/, http://www.theglobeandmail.com/