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New Study: Exposure to phthalates may affect genitals of baby boys

Sarah Janssen

Posted October 6, 2008

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By now, most people have heard of phthalates, even if they aren't sure how to pronounce it (the 'ph' is silent). Phthalates are a group of chemicals commonly used in everyday products - cosmetics and personal care products, building materials such as vinyl flooring, automobile interiors, artificial leather, and in children's toys made from PVC (for example, a rubber ducky).  

There is widespread exposure to many phthalates - the CDC has found over 75% of the population carries residues of at least 5 phthalates in their bodies. Phthalates are under scrutiny because certain ones are known to be hormone disruptors and cause a reduction in levels of the male hormone, testosterone.  When testosterone levels are reduced during critical periods, such as during development of the male genitals, abnormalities occur. At least in the lab animals, these abnormalities are permanent changes that impact fertility later in life.

To date, most of the research has been in laboratory animals, where something called "phthalate syndrome" has been used to describe the cluster of abnormalities observed in males after exposure to phthalates in the womb. These outcomes include, abnormalities in the prostate gland, small or undescended testicles, a shortening of the distance between the genitals and anus (in severe cases this is a birth defect called hypospadias), and later in life poor semen quality and infertility. 

But you might wonder, can a lab rat really predict what might happen to a human? Phthalate syndrome  thus far has only been described in rats but increasingly there are more and more human studies finding similar outcomes.  

 Previous research in humans has associated early life exposure to phthalates with a reduction in the anogenital distance, alterations in hormone levels, and in adults high phthalate levels have been associated with poor semen quality.  

Now new research has found further evidence of "phthalate syndrome" in humans.  In this latest study, baby boys exposed to higher levels of phthalates in the womb had smaller penises, a shorter distance between the anus and base of the penis, and undescended or incompletely descended testicles.  Does this sound familiar? While most of these changes are not serious problems, we know from previous research that animals born with these changes end up with lower sperm counts later in life. It isn't known whether these boys will have fertility problems but as noted in an interview with the lead researcher, is very concerning that these boys have physical changes indicative of being "less masculine".

 While some phthalates have been banned in cosmetics in the EU and 6 different phthalates have been banned in toys in the EU for nearly a decade, it was just this summer that the US Congress passed a ban on the same 6 phthalates in children's toys. However, is still legal to use phthalates in cosmetics, building materials, furniture and even for some food applications. 

Although the ban is a step in the right direction, it won't eliminate some of the major sources of phthalate exposure. Here are a few tips for avoiding phthalates:

  •  Use unscented or fragrance free products. This includes air fresheners.  NRDC did air freshener testing and found 12 of 14 brands contained at least one phthalate.
  • Look on the label for cosmetics that say "phthalate free" or check the list of companies that have pledged not to use phthalates.
  • The U.S. phthalate toy ban will not go into effect until next year.  In the meantime, buy toys that are not made from PVC, or that are labeled as being phthalate free. The San Francisco Dept of the Env has been doing toy testing and also has a website listing levels of phthalates found in toys.
  • Phthalates collect on dust particles.  Do frequent dusting but use a damp cloth or wet mop to prevent the dust particles from becoming airborne. Use a vacuum cleaner with a HEPA filter.
  • Avoid buying PVC based products that are likely to be treated with phthalates - this includes most "vinyl" products  
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MG TorkOct 14 2008 02:40 PM

Thanks for the information in this article, helpful in understanding the issue.

As an aside, in a recent BPA post, a point outside safety of BPA - that all plastics are petroleum-based and "energy intensive" was made.

Stainless steel containers and glass containers are also quite energy intensive to produce AND more energy intensive to transport to market (due to the higher densities of these materials) than most plastics which can increase other pollutants. Where safe plastics are available, they have a place in helping reduce other forms of pollution and we should always be accurate in our activism toward better stewardship.

Thanks for your consideration.

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