Tuesday, October 29, 2013

Microwaving Food in Plastics

"The testing showed that more than 70 percent of the products released chemicals that acted like estrogen. And that was before they exposed the stuff to real-world conditions: simulated sunlight, dishwashing and microwaving. 'Then, you greatly increase the probability that you're going to get chemicals having estrogenic activity released,' says George Bittner, professor of biology at the University of Texas, Austin. He added that more than 95 percent of the products tested positive after undergoing this sort of stress."
Plastic is Forever:
Plastics are typically classified by a number from #1 to #7, each number representing a different type of resin. That number is usually imprinted on the bottom of your container; flip it upside down, and you'll see a recycling triangle with the number in the middle. Here's a quick breakdown of plastic resin types:

Safer Plastics:
#2 HDPE (milk jugs, toys, liquid detergent bottles, shampoo bottles)
#4 LDPE (cling wrap, grocery bags, sandwich bags)
#5 PP (syrup bottles, yogurt cups/tubs, diapers)

These three types of plastic are the safest. They transmit no known chemicals into your food and they're generally recyclable; #2 is very commonly accepted by municipal recycling programs, but you may have a more difficult time finding someone to recycle your #4 and #5 containers.

#1 PET (disposable soft drink and water bottles, cough-syrup bottles)
Polyethylene terephthalate (PET or PETE) bottles and containers are fine for single use and are widely accepted by municipal recyclers. You won't find many reusable containers made from #1, but they do exist. It's also best to avoid reusing #1 plastic bottles; water and soda bottles in particular are hard to clean, and because plastic is porous, these bottles absorb flavors and bacteria that you can't get rid of.

Polylactide (PLA) plastics are made from renewable resources such as corn, potatoes and sugar cane and anything else with a high starch content. The starch is converted into polylactide acid (PLA). Although you can't recycle these plant-based plastics, you can compost them in a municipal composter or in your backyard compost heap. Most decompose in about twelve days unlike conventional plastic, which can take up to 100 years.

Plastics to Avoid:
#3 PVC
Polyvinyl chloride (PVC) is often used frequently in cling wraps for meat, cooking oil bottles, and plumbing pipes. However, PVC contains softeners called phthalates that interfere with hormonal development, and its manufacture and incineration release dioxin, a potent carcinogen and hormone disruptor. Vinyl chloride, the primary building block of PVC, is a known human carcinogen that also poses a threat to workers during manufacture.

#6 PS
Extruded polystyrene (commonly known as Styrofoam) is used in take-out containers and coffee cups, and non-extruded PS is used in clear disposable takeout containers, disposable plastic cutlery and cups. Both forms of PS can leach styrene into food; styrene is considered a possible human carcinogen by the International Agency for Research on Cancer. It may also disrupt hormones or affect reproduction.

#7 PC
Polycarbonate (PC) is found in baby bottles, 5-gallon water bottles, water-cooler bottles, the epoxy linings of tin food cans, and medical storage containers. PC is composed of a hormone-disrupting chemical called bisphenol A (BPA), which affects neural and reproductive development and has been linked linked to cancers, early puberty, obesity, and diabetes. A far better choice is to use glass baby bottles, which is the best baby bottle option for supervised use.

Harvard Health:
When food is wrapped in plastic or placed in a plastic container and microwaved, substances used in manufacturing the plastic (plasticizers) may leak into the food. In particular, fatty foods such as meats and cheeses cause a plasticizer called diethylhexyl adipate (DEHA) to leach out of the plastic. But the levels are very low. The levels of the plasticizer that might be consumed as a result of plastic film use are well below the levels showing no toxic effect in animal studies.

The FDA, recognizing the potential for small amounts of plasticizers to migrate, closely regulates plastic containers and materials that come into contact with food. The FDA requires that manufacturers test these containers and that those tests meet FDA standards and specifications. It then review the test data before approving a container.

What about containers without a microwave-safe label? Only those containers labeled “microwave safe” have been tested and found safe for that purpose. A container that’s not labeled safe for microwave use isn’t necessarily unsafe; the FDA simply hasn’t determined whether it is or not.

Before microwaving food, be sure to vent the container: Leave the lid ajar, or lift the edge of the cover. Don’t allow plastic wrap to touch food during microwaving because it may melt. Wax paper, kitchen parchment paper, or white paper towels are alternatives. If you’re concerned about plastic wraps or containers in the microwave, transfer food to glass or ceramic containers labeled for microwave oven use.

No comments: