Let's be clear: There's no denying the miracles provided to humanity by space-age polymers. Plastics do so many clever things, there's no imagining life without them. But here's one surprising feat they need to stop performing—the trick of adding the things they're made from to the foods they help us store.
A recent study published in the journal Environmental Health Perspectives hints that at least some of the plastics found in our kitchens appear to be getting it backwards: Instead of us storing our food in them, they're storing themselves in our food.
Researchers selected five families who regularly dine on canned and packaged foods. The families ate normally then switched for three days to a diet of foods that weren't canned or packaged in plastic before going back to their usual fare. Over the period, urine samples were checked for traces of bisphenol-a (BPA) and bis(2-ethylhexyl) phthalate (DEHP), two hormone-disrupting chemicals found in food-grade plastics. During the can- and plastic-free fresh-food phase of the operation, levels of BPA in these samples dropped by about two-thirds on average while amounts of DEHP metabolites (what's left inside us after our bodies break down phthalates) fell by more than 50%.
In the words of the study's authors, "BPA and DEHP exposures were substantially reduced when participants' diets were restricted to food with limited packaging." While it must be stressed that this is a small study that's hardly definitive, these results nevertheless suggest that our food may come with more than nutrients when it comes in plastic and that we'd be wise to adopt practices like these:
- Don't microwave any food in plastic of any kind—including so-called "microwave-safe" containers. Use only microwave-safe ceramics and glassware even if it means transferring foods from the microwaveable packages they come in.
- Don't serve or store foods, especially hot foods or foods made with fats or oils in plastic containers. Heat encourages plastic leaching, and fatty foods may more easily absorb many of the chemicals that result. Use glass, metal, or ceramics instead.
- If you opt to stash leftovers, school lunches, and other foods in plastic, use containers made from #2 HDPE, #4 LDPE or #5 PP plastics, which have been found to be generally safe for food storage.
- Avoid #7 polycarbonate food storage containers and water and infant bottles. This plastic has been found to release BPA.
- If you're unsure whether a specific container is safe but still need to use it, line it with unbleached wax paper first to ensure that food doesn't make contact with any surfaces.
- Don't wash plastic containers with dishwasher detergents containing chlorine. This harsh alkali chemical may accelerate the leaching of toxic plastic compounds.
- Avoid deli-wrap and similar products. When foods like sliced cheese and meats are sold in plastic bags and or plastic deli wrap, transfer them as soon as possible to unbleached wax paper, foil, or a safe container.
- Recycle your old plastic containers, especially those that are heavily worn and/or scratched. As plastics are more likely to leach toxins as they age, and scratches give them more microscopic surface area to do it.
- Play it safe and only use glass bottles for infant feedings. Never feed an infant out of a plastic container of any kind.
Lastly, remember what happened in the recent study: A diet of foods that hadn't been in contact with plastics or cans appeared to offer the best defense against certain unwanted chemical ingredients showing up on our daily menus. That makes your family's best bet a larder filled with fresh, whole foods and those with a minimum of packaging and processing. Stick to the good stuff, and it won't leave a whole lot sticking to you.