Most of us are aware that processed, packaged foods aren't so good for us, filled as they are with preservatives and food that's been mechanically or chemically taken apart and then reconstituted (pink slime anyone?). Now, a new study, recently published in the Journal of Epidemiology and Health has looked at what those foods are packaged in, and found that the stuff that food comes in — the shrink-wrapped plastic, the lined cans — as well as the processing equipment they are made on, can leach chemicals into those foods.

Taken as a group, the materials that are involved in the processing of food are called Food Handling Materials (FHMs), and the impacts of the chemicals in many of them (and the combinations or possible compounds by which they form in the body) are unknown. The total number of chemicals used in FHMs is more than 4,000. Known toxins, like formaldehyde, and know hormone disruptors, including bisphenol A, tributyltin, triclosan, and phthalates can all leach into food from packaging, handling or processing machines.  

"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," write the authors of the report. The effects of chronic, low levels of many of these substances in the body is unknown, as are their effects on developing fetuses. 

Establishing exactly which substances (and combinations of substances) cause health issues, and over what timeline, is difficult to test for, since there are differences in the way different people's bodies store and metabolize chemicals. Rate of ingestion varies from person to person — even among people who might live in the same house and eat similar foods. But currently, the health effects of these chemicals aren't being examined or tested for, which "casts serious doubts on the adequacy of chemical regulatory procedures."

These regulatory procedures aren't likely to change anytime soon, so if you want to protect your health, avoiding packaged, processed foods is a simple way to avoid the chemicals inherent to them. 

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Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

Chemicals in food packaging could affect your health decades later
Another reason to avoid pre-packaged, processed foods: People who eat more of them have higher levels of unhealthy toxins in their bodies.