Paper or plastic? Or aluminum, glass, styrofoam…?

As a response to his study in Pediatrics, Dr. Frank Biro eluded to the consequences of phthalate exposure and child development.  Specifically, Dr. Biro was concerned about the amount of phthalates young girls were being exposed to and the development of earlier puberty.  See my blog post from August 19th for details on this study.

What are phthalates?

Phthalates are chemicals that are added to polyvinyl chloride (PVC) products to create plastics with increased durability and flexibility.  All plastic additives, including phthalates, are found throughout our environment because they are so extensively used in the production of consumer items.  Phthalates can be found in everything from building materials and toys, to food packaging and cosmetics.

Phthalates are a relatively unstable part of a plastic product; they “break off” the plastic products they are used to create.  Phthalates are “lipophilic”, or “fat-loving”.  So, when phthalates come into contact with lipophilic substances, they leach out of the PVC and cause contamination.  Since the compounds easily degrade and are so prevalent in the environment, phthalates can be found in food, soil, even indoor air.

What do we know about phthalates?

Hundreds of studies have been done showing the consequences of phthalate exposure in scientific animal models.  Studies have led to the idea that these compounds may act as endocrine-disrupting compounds (EDCs).  EDCs describe chemicals that change how the reproductive system works, therefore changing normal development and function.  For example, EDCs are associated with a decreased reproductive success in men (see this and other works by Meeker and Hauser) and women (see this and related articles).  It remains unclear, however, how these plastic exposures effect development of young children. It is theorized the exposures may have long-term consequences on reproductive development and health.

The problem is that we have lots of research showing the effect of phthalate exposure in scientific models.  These models do not always equal effects in human subjects. Controversy exists because we can only assume damage in humans based upon these animal studies.

We know that phthalates are not immediately toxic.  It seems that repeated, chronic exposure to the chemicals causes damage.  Exposures from different sources (food, water, air) lead to different levels of toxicity.  We do know that animals can metabolize and excrete these products, but we do not know the harm that comes in the process.  We do not have a large amount of evidence showing harm in humans.

How do phthalates effect kids’ health?

Phthalates are in breast milk and infant formula.  Indoor air has a high content of phthalate derivatives since they attach to aerosolized particles.   Kids put tons of things in their mouths including plastic teethers and toys, foods stored in plastics, and even (yes) dirt.

One review has been published in Pediatrics regarding the effects of phthalates in humans.  Since we know that these compounds are EDCs, there has been much discussion within the health community about the safe amount of human exposure while additional testing and evaluation is being performed.

The NIH and CDC have performed small studies evaluating exposure in infant and younger children.  Phthalate levels in different age groups were overall higher than expected, specifically in the younger age groups.  Even with this small amount of human data, government bodies have taken some initiative on this issue.  Certain uses of phthalates are banned from children’s items in the EU.  The US and Canada manufacturers have voluntarily changes patterns of use.

More studies, in humans of all ages, are needed to evaluate the true effects of exposure to these chemicals.

While additional information is being evaluated, how can I limit my family’s exposure?

Plastics are involved in the production, manufacturing, and packaging of millions of household items and food products.  Have you ever gone to a grocery store trying to limit your purchasing to items in other forms of packaging?  Frustrating!!  There are many websites listing items to avoid.  And, as with any consumer issue, there are a lot of “extreme” recommendations on the web.  Here are some tips on what I think are reasonable ways to decrease your exposure to phthalates:

  1. Read your labels. Avoid the word “fragrance” listed in the ingredients.  “Fragrance” is a word that often represents chemical combinations including phthalates.  Some other abbreviations to avoid in the the ingredient listing are DEP, DBP, DEHP, BzBP, and DMP.  Look for “BPA-free”, “phthalate-free”, “PVC-free”, or “melamine-free” on the packaging.
  2. Limit food exposure. Do not store leftovers in plastic, choose glass instead.  Do not heat food in plastic in the microwave.  Do not wash plastics in high-heat dishwashers.  Choose foods stored in glass, glass-bottled milk for example.  Choose sippy cups, plates, and utensils in “safer” plastics.  Websites like www.thesoftlanding.com give examples of these products (I do not endorse nor have vested interest in this site).
  3. Watch your recycle codes. If glass packaging is not an option, choose items stored in containers with recycle codes 1, 2, or 5.  Avoid recycle codes 3 and 7.

As with many things, keeping a moderate opinion until more research is available is appropriate.  Hopefully, more information regarding plastics exposure and children will be available soon.