What Plastics Do to Our Bodies

By Martha Miller Johnson, Positively Green 2/2009

News of possible health threats associated with plastic bothered Jeanne Haegele of Chicago so much that she has quit using plastic. The 28-year-old marketing coordinator chronicles her efforts online at www.lifelessplastic.blogspot.com. “Plastic is absolutely everywhere–our food is packaged in it, our clothes are often made out of it, and even baby toys are made of plastic,” Haegele says. “It was scary that something that was such a big part of my life might be dangerous.”

Scientists are mostly worried about bisphenol-A or BPA. “It’s an endocrine disruptor and in numerous animal studies it’s been linked to cancer, infertility, obesity and early puberty,” says Anila Jacob, M.D., M.P.H., a senior scientist at the Environmental Working Group, a non-profit research and advocacy organization in Washington, D.C. “The CDC has found this chemical in 93 percent of people they have tested,” she says.

BPA is a chemical used to make polycarbonate plastic or items marked with the number 7 on the bottom. Some plastic dishes, cups, reusable water bottles and baby bottles are made out of polycarbonate. Heating foods in polycarbonate plastic increases the amount of BPA that leaches into food, Jacob says. Frances Beinecke, president of the National Resources Defense Council, an environmental action group, worries about BPA’s possible role in breast cancer. Beinecke, a breast cancer survivor, says BPA is a synthetic form of estrogen, and doctors know estrogen feeds breast cancer. “It ramps up cell division in pre-cancerous cells and it can prompt tumors to metastasize,” she says. “In animal studies, BPA has been found to cause the early onset of puberty and stimulate mammary gland development in females. The estrogen-like properties in BPA are so strong that even when male rodents were exposed to it, they had an increased risk of mammary tumors.” The studies done to date have all been on animals, Jacob says, because it’s difficult to study in humans as we have already been exposed via multiple routes. “We think the animal data is convincing enough that it warrants concern,” Jacob says.

BPA also is used to line the inside of metal food and soda cans and can leach from the can liner into the food. Acidic foods like tomato sauces and soda absorb more BPA. Other plastic containers–like those made with polyvinyl chloride or PVC and marked with the number 3 concern scientists for health and environmental reasons. PVC contains phthalates, softeners need to make the plastic bend and they have been found to interfere with hormonal development. The production of and burning of PVC plastic releases dioxin, a known carcinogen, into the atmosphere.

All food plastic wraps used to be made with PVC, but many large name brands have quit using PVC. However, the cling wrap used for commercial purposes, such as the meat department of your grocery store, often contain phthalates. Gina Solomon, M.D., M.P.H., a senior scientist with the NRDC, suggests checking the date when you buy food wrapped in cling wrap. Buying something recently wrapped is your safest bet, she says.

For its part, the FDA agrees that substances used to make plastics can leach into food. But the agency says it has studied them and found “the levels to be well within the margin of safety based on information available to the agency.”

Safer Plastics

  • #1 PETE or PET (polyethylene terephthalate)–used for most clear beverage bottles, such as 2-liter soda, cooking oil bottles and peanut butter jars. One of the most commonly recycled plastics on the planet.
  • #2 HDPE (high-density polyethylene)–used to make most milk jugs.
  • #4 LDPE (low-density polyethylene)–used in food storage bags, some cling wraps and some squeeze bottles.
  • #5 PP (polypropylene)–used in opaque, hard containers, including some baby bottles and some cups and bowls. Drinking straws and yogurt containers are sometimes made with this.

Avoid These

  • #3 PVC (polyvinyl chloride)–used in commercial plastic wraps and salad dressing bottles.
  • #6 PS (polystyrene)–used in Styrofoam cups, meat trays and “clam-shell”-type containers.
  • #7 Other (these contain any plastic other than those used in #1-6. Most are polycarbonate which contain BPA)–used in some water bottles, Nalgene water bottles, some baby bottles, and some metal can linings.

Easy Tips

  • Using plastic water bottles? Go for a metal or stainless steel container instead.
  • Using a plastic spatula? Try using a wooden spoon instead.
  • Using Tupperware? Try pyrex glass containers that go straight from the fridge to the oven.
  • Buying ready-to-drink juices? Frozen concentrate stores longer and is typically packaged in paper.
  • Using plastic cutting boards? How about a bamboo cutting board?
  • Using a plastic lunch box? A stainless steel laptop lunchbox provides a sturdy, elegant alternative.