Plastic Problems

Recently I did a two-part podcast with KMO at C-Realm on backyard poultry and toxic burden. During the interview I mentioned some of the potential health issues associated with plastic water bottles. I particularly mentioned bisphenol A (BPA), a chemical found in hard plastics, such as the polycarbonate water bottles that so many people carry today.

BPA is an endocrine disrupting chemical, implicated in a variety of things that are troubling us. The evidence is especially strong that it causes fetal toxicity, which can result in either miscarriage or still birth. It's also connected with reduced conception, usually caused by low sperm counts or abnormal sperm production in men and/or menstrual disorders in women, and several developmental disorders and birth defects. Two that I heard a lot about while attending a conference* this year are chryptorchism (undescended testicles), and hypospadia, a condition in which the opening in the penis is along the shaft, rather than at the tip. Hypospadia, the now the second most common congenital birth defect, having increased in frequency 300% in just the last 30 years.



After hearing the podcast, one of KMO's listeners sent an email asking, "So does this go for all plastic water bottles (like the kind used for mountain bikes too?) I also send my kids to school with water bottles, so I wonder what a good substitute for those would be. I guess metal since glass could get broken."

I decided to answer the listener's question here:

First, as far as BPA goes, it is in polycarbonate plastics (which has a number 7 in the recycle mark). That includes most of the plastic water bottles like bikers use. The other common plastic bottles (that soda, juice, and water usually come in) are a softer plastic than polycarbonate. Known as PETE (for polyethylene terephthalate, and recognized by number 1 in the recycle mark), these plastics don't contain BPA, but do contain phthalates, another plasticisizing chemical that is associated with many of the same problems as BPA.

What can you do? Reduce your exposures to these chemicals (and especially your children's exposures). How? Start by choosing glass and steel when those options are available. For example, for hot or cold drinks that you carry with you, try stainless steel containers that aren't resin coated on the inside. Check Kleen Kanteen.

Some years ago, I also consciously switched from using plastic for most food storage, to using lots more glass for food storage. Ball jars (the canning jars of yore) are great for storing left overs of all kinds in the fridge — you can see what's in them, and they really do seal well. The tops can be reused hundreds of times when the food is in the fridge (unlike when they are actually used for canning purposes). I use them for storing almost every kind of food imaginable, including cheese, meat, and raw veggies. If you look in my fridge, about the only plastic you normally see is bread in its plastic bag.

Coming tomorrow: Part 2 of what you can do to reduce exposures!

* The conference was co-sponsored by the Collaborative on Health and Environment and the School of Medicine at the University of California-San Francisco. The Summit on Environmental Challenges to Reproductive Health, was held in January, 2007 at UCSF.

Endocrine Disruptors Part 1

According to the Environmental Protection Agency's definition, endocrine disruptors are chemicals that "interfere with the synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body" and from an environmental health standpoint, they are of major concern. Why? Because, hormones are naturally occurring substances, produced in the body, which act as messengers, sending signals that tell genes, cells, and systems to turn on, turn off, increase production, or decrease production. Most are associated with the endocrine system, which includes the pituitary, pineal, thyroid, parathyroid, and adrenal glands as well as the pancreas, ovaries, and testes. Endocrine glands and organs produce and release twenty different hormones that are critical in regulating growth and development, mood, tissue function, and reproduction. Like a key and lock, each hormone (the key) is associated with specific genes or cells that have receptors (the lock) for that hormone.

Let's take a closer look at how hormones influence reproduction: Just two cells, a sperm and an egg, each carrying a set of instructions embedded in molecules of DNA, join together and direct the choreography of life: Forty hours after fertilization, the cells have divided four times; by three days, twelve cells have formed. The second week, the cells begin differentiating, and by eight weeks, the organs have begun forming and the heart begins beating. At birth those two cells have transformed into trillions.

If all goes well during the development dance a healthy baby enters the world, but this dance is intricately complex—a blend of eloquent ballet, some wild cha-cha, a turn or two of twist and shout, and a bit of polka. It relies on a mind-boggling set of exquisitely timed biochemical processes, controlled by unfathomably minute quantities of hormones. These hormones act as conductor, keeping the band on beat. Just one missed beat or crossed step, and the dancers—those emergent cells that are dividing and transforming into eyes and ears, fingers and toes, livers and lungs—go astray, and the pregnancy ends in miscarriage, or a child born with birth defects or chronic health problems such as asthma, ADHD, or autism. Missed beats and missteps also increase the odds of adult-onset health and reproductive problems, or may even cause problems in the children and grandchildren of generations to follow.

Unfortunately, this dance is one that clearly seems to be going off beat more and more often: impaired fecundity (or the inability to conceive or carry a child to term) is a problem that affects at least 12% of women and their partners who are of childbearing age and trying to get pregnant, and that number may be quite conservative because it’s based on the number of women seeking help at fertility clinics, thus losing count of those who can’t afford to seek such help, or who choose not to.

Your first thought might be, “Well, women are waiting longer to conceive, so its logical that conception is down,” but that assumption caves under scrutiny: "Fertility levels have declined 50% worldwide between 1950 and 2000," Shanna Swan, a reproductive epidemiologist at the University of Rochester Medical Center, said at a recent conference (held in January at the University of California San Francisco) on Environmental Challenges to Reproductive Health and Fertility. “The most disturbing news is that the greatest increase in infecundity is among women under 25. These women and their partners should not be subfertile.”

What Swan, and dozens of other scientists presenting at the conference pointed to as a likely driver of this trend is endocrine disrupting chemicals--and there are thousands of them.

Coming tomorrow: Part 2