“I want to say one word to you. Just one word,” enthuses Mr. McGuire in the 1967 movie “The Graduate.” Benjamin Braddock, the graduate of the title, listens meekly for the big reveal:
Then as now, plastics are all-American, the easy way to convenience, comfort, and (according to Mr. McGuire) cash. Most Americans have cupboards full of plastic containers, from Tupperware and GladWare to sandwich bags and Saran Wrap. But as we learn more about the safety of using plastic to store food, we’re becoming wary of it. Should we use aluminum foil or waxed paper instead? Or glass containers? Which are best for the environment and our health?
The packaging problem really begins in the grocery store. Is that organic, grass-fed beef truly packaged in food-safe wrap? (Probably.) Should I buy 12 single-use containers of yogurt or the gargantuan tub? (The big tub — unless you’re not going to eat it fast enough.) Is it better to buy five pounds of flour packed in paper or scoop it from the bulk bin into a plastic bag? (Depends.)
Trying to go green when it comes to food packaging is really an exercise in shades of gray, says Chris Doyle, the operations manager at Pioneer Organics, a Seattle-based organic groceries home-delivery service. “A plastic bag [or container] is a challenge any way you look at it,” he says. “What has the least post-purchasing effect, making less garbage in the world and having the bag break down in a reasonable amount of time?”
Here’s a boxed set of food-storage options, including plastic, aluminum, waxed paper, and glass.
Earl Silas Tupper, who launched the Tupperware company in 1938, is credited with creating plastic food-storage containers for home use. Today Tupperware is just one player in the plastic-container game, with numerous manufacturers producing bins in seemingly endless configurations and sizes. These airtight containers keep food fresh, so what’s not to like?
Well, recent scientific studies have raised concerns over the chemicals used in plastic food containers and whether they leach into the foods kept inside. “Bisphenol A is a chemical that’s used in a variety of consumer products, including food containers and plastic wraps,” says Anila Jacob, a senior scientist with the Environmental Working Group, an environmental-research nonprofit based in Washington, D.C. “It mimics the acts of [the hormone] estrogen. This chemical — at very low levels — is associated with breast cancer, prostate cancer, infertility, ovarian diseases, and early puberty.”
Jacob notes that a Centers for Disease Control and Prevention survey found bisphenol A in 95 percent of its 400 test participants. Bisphenol A can leach into food if the plastic begins to break down. “Two things cause the plastic to break down: heating it or intense washing,” says Vincent Cobb, the founder and president of Reusable Bags, a website that sells reusable bags and other products designed to help consumers reduce, reuse, and save.
Bisphenol A is found in polycarbonate plastics, classified by a number 7 recycling code on the bottom of the container. Typically, these are used in Nalgene water bottles and baby bottles, but other containers are made with it too, including Tupperware Rock ‘n Serve. (In April, after the Canadian government announced that it would declare bisphenol A toxic, Nalgene announced that it would no longer use bisphenol A in its bottles.)
In addition to bottles, the insides of canned goods are often lined with an epoxy resin containing bisphenol A. An Environmental Working Group study tested 97 types of commonly eaten canned food and found bisphenol A in more than 50 percent of the cans.
“Try to avoid [number 7] plastics as much as possible,” says the EWG’s Jacob. “If you’re going to use plastics for storage, don’t ever microwave them.”
Paul McRandle, the deputy editor of National Geographic’s green-consumer publication the Green Guide, also recommends washing polycarbonate plastics by hand. “The more distressed it is, the more it can melt,” says McRandle.
The Environmental Working Group encourages people to decrease the amount of canned food they consume. Not only will you reduce your bisphenol-A exposure, but fresh food is better for you, Jacob says.
Most plastics used for food storage sport the recycling numbers 4 and 5. These numbers indicate the type of resin used to make the plastic. Number 4 uses a low-density polyethylene, also noted by the initials LDPE. Number 5 is made from polypropylene, noted as PP. (Plastic bags, such as sandwich baggies and ziplock freezer bags, are usually made from plastics numbered 4 or 5.) Most research has not shown any leaching of harmful chemicals from number 4 and 5 plastics, reports the Green Guide.
LDPE is the most common plastic used in ketchup bottles, yogurt and margarine tubs, as well as GladWare, Rubbermaid, and Tupperware containers. PP is often used to make bread bags, squeezable bottles, and plastic freezer bags. McRandle lauds freezer bags for helping preserve fresh food. “We don’t have a blanket loathing of plastic. It does make a greener lifestyle possible,” McRandle says.
Although the Green Guide lists containers made with LDPE and PP plastics as food-safe based on current research, some food-industry experts have rid their kitchens of plastic. “I don’t store in plastic; I store in glass. I guess the only thing plastic is the lids,” says Goldie Caughlan, the nutrition educator for the Seattle-based PCC Natural Markets.
Caughlan tries to avoid plastic containers at the store, although she realizes making homemade yogurt is out of reach for most of us. Many consumers take pride in reusing their resealable yogurt containers, and there has been no outcry from scientists about this practice. Still, Caughlan believes these containers were not intended for sanitizing and reusing. She encourages her students to recycle them or put them to uses beyond food containment, perhaps for potting seeds or storing nails.
The safety factor of plastic and cling wraps is dependent on the type of chemicals used to make the plastic. For instance, clear food wrap is sometimes made out of polyvinyl chloride, also known by the recycling code V or PVC (number 3), which is a known human carcinogen.
The Green Guide says: “PVC’s manufacture and incineration release dioxins, which are carcinogens and hormone disruptors. In contact with foods, especially hot, fatty foods, PVC can also leach chemicals such as adipates and phthalates, shown in mice to cause birth defects and damage to the liver and kidneys.” The Green Guide also notes that PVC isn’t accepted by the majority of community recycling centers.
Culinate’s features address the practical challenges and joys of food.
Want more? Comb the archives.
Change in our kitchens
Reflections on cooking — and a career that’s based largely at the stove.
Flatbreads from around the continent
Beyond a supporting role
The great Sicilian-Neapolitan kitchen rivalry
Five ideas each month for eating better