By Royce K. Bailey M.D., M.P.H., F.A.A.C., M.A.A.C.

Plastics are one of the greatest inventions of all time.  Modern life depends on them.  They are in everything from appliances, insulation, cars, clothing, to food and water containers. etc.  Are plastics making us sick?  Which ones, if any?

Going Green
So you’re trying to be green and reuse your plastic water and juice bottles, butter/margarine tubs and plastic food storage containers.  STOP IT!!  85% of the rest of the world throws away this stuff without recycling.*   Recycle it, don’t re-use it.

BPA=A Hormone Disrupter 
Bisphenol-A (BPA) is an endocrine/estrogen-like disrupting chemical in animal studies.  At low doses, BPA causes cell and tissue changes that can cause early puberty, behavior problems, breast and prostate cancer, altered immune function and metabolic problems.  The CDC reported in 2008 that 93% of tested individuals had BPA in their urine.  Higher levels were seen in woman and children.  It was first synthesized in 1891, BPA came into use as a synthetic estrogen in 1936.  It was passed over for a stronger synthetic estrogen diethylstilbestrol (DES) in the 1940s.**  In the 1950s, chemists discovered that, combined with phosgene (used during World War I as a toxic gas) and other compounds, BPA yielded the hard, clear, lightweight, polycarbonate plastic of shatter-resistant headlights, eyeglass lenses, DVDs and baby bottles.  In the US, BPA has been in the lining of food and beverage cans since 1963.  Japan has replaced BPA to line their cans since 1997 with natural resin.  BPA is crucial in making polyester.  In the U.S. alone more than 2.3 billion pounds (1.04 million metric tons) of BPA is manufactured annually.

How Do You Get BPA In Your Body
BPA is found in those indestructible water bottles (not the disposable ones), sippy cups, pacifiers, beauty supplies, toys, running shoes, etc.  During the manufacturing process, not all BPA gets locked into chemical bonds.  That residual BPA can work itself free, especially when the plastic is heated, whether its a Nalgene bottle in the dishwasher or hot car or a food container in the microwave.  BPA can also be picked up by humans in the soil, water and dust.  By putting boiling water in new and old BPA-type polycarbonate bottles released 55 times more BPA.  Acidic foods, like tomatoes, and fatty foods (like gravy) causes more leaching of BPA from their cans.  The Environment Working Group found BPA in more than half of the 97 food cans it tested, with the highest levels coming from chicken soup, infant formula and ravioli.  The FDA estimates that the average adult American consumes, on average, a cumulative 11 micrograms of BPA a day through diet, mostly from canned foods.  Is that too much?  Most adults process it in less than a day, it is broken down into glucuronide, but babies and fetuses do not excrete it quickly.

Human Studies
Studies in humans are limited, but the American Medical Association (JAMA) found high levels of BPA was associated with heart disease, diabetes Type 2, and abnormal liver enzymes.  This did not prove that BPA caused these problems.  Most manufacturer and retailers are phasing out BPA and phthalates in their products, including Walmart, CVS, Nike and Proctor and Gamble.  Canada has called it a “toxic substance.”  California and other states are trying to ban polycarbonate with BPA.

What Makes The Poison?
Toxicologists function under the well known theory that “the dose makes the poison”– the more chemical you ingest, the sicker you get.  That’s why the FDA states that you are safe.  You would have to ingest 500 pounds of canned foods and beverages a day to reach the safety standards set for BPA in the US and Europe.  But if you are not directly poisoned, could you be harmed by BPA and phthalates?   BPA and phthalates are endocrine disruptors–chemicals that interfere with, mimic, shut down or modify the chemical signals that regulate everything from metabolism and reproduction to our bodies’ response to stress.  Therefore, by theory, tiny doses can cause problems if the exposure is at a critical time in development.  SO, the volume of the foreign chemical may not be as important as “the timing makes the poison”  Not until recently could these tiny doses be even measured.  Is it possible that early exposure to chemicals like BPA makes us grow up to be chubby, infertile and prone to sickness as children and adults?  This is the thinking of many in the medical community who feel vaccines, given at the wrong time, may trigger autism.

Phthalates
BPA contains phthalates (a wide range of chemicals).   Phthalates are in car dashboards, vinyl shower curtains, raincoats, and even your rubber ducky, to make them pliable.  Phthalates are in beauty products, like nail polish to prevent chipping.  75% of 2450 men, women and children tested (ages 6 to 85) had seven different phthalates in their urine.  Children had the highest chemical levels.  Lower sperm counts and other reproductive abnormalities were found in men with the highest levels of certain phthalates in their urine.  In girls, phthalate levels seven times higher than the control group correlated with early puberty (breasts at age 2 to 6) in Puerto Rico.  Early puberty has been linked to cancer (breast and prostate).  People with higher than average phthalate levels tended to have larger waists and increased insulin resistance.  Higher levels of BPA and phthalates during fetal and childhood development could affect the brain structure, function and behavior, like causing attention deficient hyperactivity disorder (ADHD), scientists suggest.  It does in rats and mice.  High BPA levels can interfere with chemotherapy.

Xeno Estrogens
Further complicating this issue is the stew of other estrogen-mimicking chemicals to which we are routinely exposed.  Synthetic xeno estrogens (one of many hormone disrupters) not only comes from BPA and phthalates, but are released from other plastic products like dental sealants; are in makeup, hair spray, shampoo, pesticides and meats, to name a few.  Europe has outlawed hormone treated meat, including estradiol (one form of estrogen***), but it is routinely used in cows in North America, Australia, New Zealand and Argentina.  North America has the highest rate of breast and prostate cancer in the world.  How much estrogen from meat are Americans getting?  The FDA says very little; the European researchers say a lot.  Investigators today indicate that our environment is saturated with chemicals that act like estrogen in our bodies, including BPA.  Synthetic estrogens collect in our fat and are more biologically harmful/active than natural estrogens by negatively affecting our DNA.

Phytoestrogens-Plant Estrogens
Virtually everything we eat -- grains, beans, nuts, seeds, seed oils, soy, flaxseed, berries, fruits, roots, vegetables, cabbage, alfalfa and fennel -- contains phytoestrogens.  Phytoestrogens change the way estrogen is metabolized by blocking conversion of estrone to dangerous 17B estradiol.  They also decrease (down regulate) estrogen receptors (doorways on the cells), thus reducing the amount of estrogen (yours or synthetic) that gets into your cells.  Phytoestrogens also stop the production of estradiol, by inhibiting the enzyme "aromatase".  They also occupy, thus neutralizing, the estrogen receptor sites to prevent harmful estrogens from turning on potentially destructive pathways.  This is done by binding to estrogen synthetase, thus inhibiting production of harmful estrogen in the body.  Researchers continue to say mixed phytoestrogens are not harmful at dietary doses!  So eat a plant based diet to protect yourself.

Oops? I Just Micro Waved That In Plastic!
So you just took out the left overs and put them in the microwave and covered them with plastic wrap.  Are you going to die???  Good Housekeeping did a study to see if any BPA/Phthalates leeched into the micro waved food from the plastic.  The good news was the products tested contained no phthalates or BPA and they did NOT pick up any after micro waving.  Here are the products tested:

Tupperware CrystalWave lid
Tupperware Rock ’N Serve container
Tupperware Rock ’N Serve lid
Rubbermaid EasyFind Lids lid
Rubbermaid Premier lid
Glad SimplyCooking Microwave Steaming Bags
Ziploc Brand Zip ’n Steam Microwave Steam Cooking Bags
GladWare Containers with Interlocking Lids container
GladWare Containers with Interlocking Lids lid
Ziploc Brand Containers with Snap ’N Seal Lids container
Ziploc Brand Containers with Snap ’N Seal Lids lid
Webster Industries Good Sense storage container
Webster Industries Good Sense storage container lid
United Plastics 21 oz Bowl
Saran Premium wrap
Saran Cling Plus Clear Plastic Wrap
Glad Cling Wrap Clear Plastic Wrap
Reynolds Clear Seal-Tight Plastic Wrap
Ziploc Brand Storage Bags with Double Zipper
Ziploc Brand Freezer Bags with Double Zipper
Glad Freezer Storage Bags
Reynolds SlowCooker Liners
Kid Cuisine All Star Chicken Breast Nuggets container
Kid Cuisine All Star Chicken Breast Nuggets film cover
Stouffer’s frozen Homestyle Classics Lasagna with Meat & Sauce tray
Stouffer’s frozen Homestyle Classics Lasagna with Meat & Sauce film covering Tupperware CrystalWave container
The following items contained low levels of phthalates or PBA but the chemicals did not leach into the food during microwave heating:
Rubbermaid EasyFind Lids container
Rubbermaid Premier container
Glad Press’n Seal Multipurpose Sealing Wrap
Glad Food Storage Bags

Recycling Number
Many plastic items are marked with a resin ID code, usually a number (1 through 7) or a letter abbreviation, which indicates a particular type of plastic. The code is typically found on the bottom of a container and is often displayed inside a three-arrow recycling symbol.  Resin ID codes are used to help identify different plastics for recycling.

Plastic #1: Polyethylene Terephthalate (PETE)  
Common uses: 2 liter soda and juice bottles, cooking oil bottles, peanut butter jars.  This is the most widely recycled plastic and often has redemption value under the California "Bottle Bill."   #1 plastic contains no BPA, but  these bottles contain a potentially carcinogenic element (something called diethylhydroxylamine or DEHA).  They are safe for a single use only, but if you must keep them longer, it should be no more than a few days, a week max, and keep them away from heat as well.

Plastic #2: High Density Polyethylene (HDPE)
Common uses: detergent bottles, milk jugs, bleach, motor oil, grocery bags, bullet proof vests and yogurt containers.  HDPE is the most popular plastic in the world and environmentally friendly.

Plastic #3: Polyvinyl Chloride (PVC)
Common uses: plastic pipes, outdoor furniture, shrink wrap, water bottles, salad dressing and liquid detergent containers.

Plastic #4: Low Density Polyethylene (LDPE)
Common uses: dry cleaning bags, produce bags, trash can liners, food storage containers and trays, play ground slides and six-pack soda can rings.  #4 LDPE has more carbon chains than #2 HDPE.

Plastic #5: Polypropylene (PP)
Common uses: bottle caps, drinking straws, ropes, thermal underwear, carpets, laboratory equipment, hernia mesh, surgical suture, loudspeakers, automotive components and stacking chairs.  PP resists fatigue, but can break down in UV (sun) exposure.  Recycling centers almost never take #5 plastic.

Plastic #6: Polystyrene (PS)
Common uses: packaging pellets or "Styrofoam peanuts," cups, plastic tableware, meat trays, take-out "clam shell" containers.  PS breaks down when exposed to acid solutions, such as adding lemon or tomato to foods, or when food contains vitamin A, or is micro waved.  It is a known human neurotoxin and a known animal carcinogen.

Plastic #7: Other
Common uses: certain kinds of food containers, ipod cases, sun glasses, DVDs and Tupperware.  This plastic category, as its name of "other" implies, is any plastic other than the named #1-#6 plastic types.  These containers can be any of the several different types of plastic polymers.   #7 plastic indicates that the plastic may contain BPA, but not always.  Recycling centers cannot recycle plastic #7.

Tips for safety
1.    Instead of polycarbonate plastic water bottles, baby bottles etc, use glass, stainless steel or aluminum bottles.
2.    When possible avoid containers that have #7 on the bottom, especially for infants and children.  Safe plastics for kids are #1, #2, #4, and #5 which contain no BPA.
3.    If you use polycarbonate bottles don’t put hot liquids in them, this releases BPA  Wash these by hand, not in the dishwasher–hot water releases BPA.  Don’t keep them in the sun or your hot car.  Don’t put them in the microwave.
4.    Opt for food in jars or cartons instead of cans–better to eat fresh/raw or frozen foods.  Acidic and fatty foods leech BPA from their cans.  If you are feeding a baby, powdered formula is safer than canned liquid formula (unless it states BPA free).
5.    Don’t reuse plastic water/soda/juice bottles.  These have no BPA in them but they may contain bacteria that is impossible to clean out.  These bottles if degraded by repeated washing, dishwasher, scratches leech a trace toxic metal antimony.
6.    Don’t microwave or heat foods in plastic containers.  This includes all plastics because when you heat plastic, even if it doesn’t contain BPA, heat will release other plastic chemicals that are harmful.
7.    The American Chemistry Council reports that phthalates are no longer being used in plastic wraps since 2006.  I still would recommend glass containers in the microwave, with glass tops or a paper towel to cover the dish instead of plastic wrap.

* The average American tosses four pounds of trash a day.
**DES was given to pregnant women to prevent miscarriages.  It caused an unusual cancer of the reproductive tract in the young women who were exposed in the womb, less so but causing testicular cancer in the men exposed in the womb.  Scientists have cataloged a long list of reproductive and other abnormalities linked to DES.
***Estradiol: This is the estrogen correlated with the highest incidence of breast, ovary and uterine cancers.

References:
Williams, F., “Is It Safe To Heat Food In Plastic?,” GoodHousekeeping.com; 2009

Hunt, P., “Microwave In Plastic?” BottomLine.com; 2/1/09:14

“Tough Questions About A Hard Plastic” Wellness Letter, University of California, Berkeley; 25 (5), 2/09:1-2.

Seliger, S., “BPA:5 Tips To Avoid The Danger In Plastics;” 2009.
http://www.fda.gov/oc/opacom/hottopics/bpa.html

Lang IA, "Association of Urinary Bisphenol A Concentration With Medical Disorders and Laboratory Abnormalities in Adults" 2008.  http://jama.ama-assn.org/cgi/content/full/300.11.1303.
en.wikipedia.org/wiki/Bisphenol_A

Adlercreutz, H. "Inhibition of Human Aromatase by Mammalian Lignans and Isoflavonoid

Phytoestrogens,” J Steroid Biochem, 1993; 44:147-153.
Andersson, A., "Exposure to Exogenous Estrogens in Food.

Possible Impact on Human Development and Health,” Eur J Endocrin, 1999;140:477-85.

Adlercreutz, H., "Dietary Phytoestrogens and Cancer: In Vitro and In Vivo Studies,” J Steroid Biochem Mol Biol, 1992; 41:331-337.
www.bisphenol-a.org

Hinterthuer, A., “Just How Harmful Are Bisphenol-A Plastics?” September 2008; Scientific American Magazine.