I have my spiels. I have a summer safety spiel about sunscreens and insect repellents. A winter safety spiel about helmets for skiing and not venturing out on thin ice. Then there are the year-round safety spiels. Wear your seat belt. Look both ways. Don't talk to strangers. It's my job to keep kids safe.
Increasingly I find myself having to give environmental safety spiels. Children are uniquely vulnerable to environmental contaminants for a number of reasons. For one thing, infants and young children tend to mouth objects. Children also breathe proportionally more air than adults and are also closer to the ground and so are exposed to more contaminants in soil and dust. Lastly, children's still-developing nervous and endocrine systems may be more at risk.
One group of environmental hazards I've found to be of particular potential risk to children is of plasticizers. Plasticizers are man-made chemicals used in the manufacture of many household plastic products. Two kinds in particular are of concern. Phthalates are chemicals added to poly-vinyl-chloride (PVC) products to make them soft and flexible. Bis-Phenol A or BPA has the opposite effect. It is used to impart hardness to certain kinds of plastics such as polycarbonate.
Phthalates are used in medical devices like intravenous tubing, but also in food packaging and baby toys like rubber ducks, bath books and soft vinyl blocks.
BPA can be found in many baby bottles and sippy cups. BPA is also used in some composites and sealants used in dentistry.
Phthalates are also ubiquitous contaminants in soil, air and dust. One particular phthalate, diethylhexylphthalate or DEHP, is produced at the rate of almost 2 tons per year. Human exposure comes largely from food contaminated during growing, processing or packaging.
So what exactly are the health risks of plasticizers? Both phthalates and BPA are known as endocrine disrupters. They can act like hormones in the body or block the actions of the body's own hormones. There are few studies on the effects of these chemicals on human health, therefore much of our knowledge is extrapolated from animal studies. Rodents exposed to high levels of phthalates in utero had an increased incidence of abnormalities of the male reproductive tract as well as decreased birth weight. In animal studies, BPA exposure was associated with early puberty as well as increased body weight.
Still the real risks of these chemicals to humans are unclear and can be interpreted differently by various entities. For example, in 1999 The American Council on Science and Health issued the so-called "Koop Report" which stated that certain phthalates were unlikely to pose a health risk to children. On the other hand, that same year the European Union banned certain phthalates in the manufacture of children's toys. As I write this article U.S. lawmakers are considering a ban on using phthalates in toy manufacture in this country.
Exposure to phthalates and BPA is hard to avoid, partly because manufacturers are not required to list these chemicals as contents of their products. Some products market themselves as "phthalate-free" or "BPA-free." For example, Born Free makes baby bottles and sippy cups without BPA. Eden Foods avoids BPA in its canning process. Since the European Union bans certain phthalates from toy manufacture, buying EU-approved toys provides a certain degree of protection.
Recycling codes (those little numbers inside the triangles on the bottoms of plastic containers) can also provide clues to chemical content. For example, No. 3 plastics seen in plastic toys and food packages may contain phthalates. Hard plastic containers with the No. 7 may contain BPA. Therefore it is best to avoid both of these categories of product.
Because chemicals leach out of plastic when heated, avoid microwaving plastic bottles or food containers. Discard old scratched bottles as well. And as always, keep reading and learning about environmental health. One Web site that I have found helpful is the one run by the Children's Environmental Health Network which is http://www.cehn.org.
Dr. Carolyn Roy-Bornstein is a board certified pediatrician with Merrimack Valley Child and Adolescent Health and Merrimack Valley Hospital. Her office is at Merrimack Health Center, 62 Brown St. adjacent to the hospital. She can be reached at 978-521-8108. Parents are invited to e-mail questions for future columns to CRoy.MVCAH@comcast.net.