Many of the synthetic chemicals involved in packaging and storing the food we eat can leak into it, potentially harming our long-term health, say environmental scientists in a paper published in the Journal of Epidemiology and Community Health.
Although some of these chemicals are regulated, people come into contact with them almost every day through packaged or processed foods. The authors of the commentary note that exposure is low, but it is chronic, as many of us eat such foods throughout our lives.
Food contact materials (FCMs) are usually made of plastic or contain a synthetic material that is in direct contact with foods. This includes coating, laminate in beverage cartons or the closures of glass jars.
Too little is known about the long-term impact of chronic exposure to these FCMs, say the authors, who add:
"These facts may be of relevance to scientists interested in the developmental origins of health and disease hypothesis (DOHaD), life-course effects of in utero and childhood environmental exposures, plasticity, epigenetics and related processes."
The team cites three main reasons for why long-term exposure to these chemicals "is a cause for concern."
'Consumers exposed to known toxicants'
The first cause for concern, say the authors, is that certain "known toxicants" - including formaldehyde, a substance known to cause cancer - are used legally in FCMs. Plastic bottles used for carbonated drinks, for example, usually contain low levels of formaldehyde.
Food contact materials are made of plastic or synthetic materials that are in direct contact with foods. They can include coating, laminate in beverage cartons or the closures of glass jars.
Another point the authors make is that hormone production-disrupting chemicals, such as bisphenol A (BPA), tributyltin, triclosan and phthalates, can also be present in FCMs.
The authors write:
"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."
Their third cause for concern is that the number of known chemical substances intentionally used in FCMs is over 4,000.
They also note that routine toxicology analysis does not consider potential cellular changes caused by FCMs, which "casts serious doubts on the adequacy of chemical regulatory procedures."
'Gaps in knowledge need to be filled'
But how can this issue be addressed? The authors say establishing a link between long-term FCM exposure and chronic diseases is a difficult endeavor, as there are no unexposed populations to compare results with.
Additionally, they say large differences in exposure levels between individuals and certain population groups are likely to exist.
They suggest using population-based assessments and biomonitoring to uncover any potential associations between FCMs and chronic conditions including cancer, obesity, diabetes and inflammatory disorders.
In developed countries, chronic diseases account for around two thirds of deaths, the team notes, adding that about 16% of these deaths happen before the age of 60.
"Since most foods are packaged and the entire population is likely to be exposed," they write, "it is of utmost importance that gaps in knowledge are reliably and rapidly filled."
In 2013, Medical News Today reported on a study that suggested pregnant women should be aware of unintentional chemical exposure.