Phthalates and Testosterone

phthalates and testosteroneI just came across an interesting paper titled Human Testis Steroidogenesis is Inhibited by Phthalates. And it’s a good one…or bad depending on your perspective.

The purpose of this research was to examine the impact phthalates have on Steroidogenesis, or the formation of steroids by the adrenal cortex and testicles. It’s a very long paper, so lets just cut to the chase and look at how the scientists summed up their findings in the conclusion…

We provide the first evidence that (phthalates) can inhibit testosterone production in the adult HUMAN testis. Note the word human…not rat. Phthalates are a family of chemicals used in plastics and many other products…and scientists learned long ago that they’re toxic to rat testis. But this was the first study to test it on human testicle cells directly; and they responded just like rat testicles do…

Quote Number 2:

In both models (phthalates) significantly inhibited testosterone production. Note the word Significant. One more reason to avoid plastics, or any other product that emits a strong smell, no matter how lovely the scent. Because aside from making plastic soft and pliable, phthalates also absorb odors, so you’ll find them in scented things like cologne, shampoo, soap and deodorant. Whenever you pull a product off the shelf at the grocery store that has a strong fake scent; it very likely contains plenty of this testosterone suppressing chemical.

But that’s not the only place you’ll find it…

Manufacturers of phthalates often deny this; but that New Car Smell everyone knows about is largely created by the soup of phthalates found in the plastic materials used to build cars interior. And you’ll find a similar smell when you whiff new shower curtains, carpets, flooring, roofing, hoses, and even injection molded shoes. Because this chemical is in the manufacture of almost everything with plastic.

Phthalates & Endocrine Disruption

A second study published in the Journal of Clinical Endocrinology & Metabolism verified that phthalate exposure causes significant declines in testosterone production, but not just in men, but in women and children as well. Here’s a quote from John D. Meeker, lead author of this study: We found associations between markers of phthalate exposure and testosterone levels among multiple age groups and in both sexes, including children.

This second study is one we really need to pay attention to because scientists tested for 13  different urinary phthalates; then checked serum testosterone levels in more than 2200 people of both sexes.

So the the sample size was large and diverse and they tested for several different phthalate metabolites. And they found that those who had multiple phthalates in their blood experienced the most significant decline in testosterone. As a matter of fact, in one group T levels plummeted by a massive 24 percent.

Phthalates and Male Fertility

In our final paper, federal researchers followed 501 young couples for four years and monitored them as they attempted to have children. And the researchers found that phthalate are much more likely to cause fertility problems in men than in women. According to Germaine Buck Louis, the lead author of this paper… It’s the males in the study that are driving the effect…they’re the signal.” After the paper went live the New York Times picked up on it, interviewed the scientists and wrote an excellent article.

Here are a two quotes…

A growing body of work over the last two decades suggests that phthalates can rewire the male reproductive system…interfering with the operation of androgenic hormones, such as testosterone, that play key roles in male development.

That mechanism, some experts believe, explains findings that link phthalate exposure to changes in everything from testicular development to sperm quality.


So here’s what you need to take from this… Excessive exposure to phthalates can rewire the male reproductive system and negatively impact testicular development, semen quality and androgenic hormones…including testosterone. So its important you take steps to avoid scented manufactured products, such as cosmetics, household cleaners, air fresheners, etc. You should also avoid plastics whenever possible and start using glass, wood and metal to store and prepare food.

And finally…

When you buy a new product that has a strong, new car smell when you open the box; place it outside for 48 hours to allow the phthalate gasses to escape before you bring it into your house.


Urinary Bisphenol A, Phthàlates, and Couple Fecundity Human testis steroidogenesis is inhibited by phthàlates Phthàlates Linked to Testosterone Reductions in Both Genders

Related Posts

Testicle Facts That You Need To Know!  Interesting Testicle Trivia

Testicle Facts That You Need To Know!  Interesting Testicle Trivia

Use HER Body Odor To Spike YOUR Wood

Use HER Body Odor To Spike YOUR Wood

How To Increase Penile Girth With Natural Methods

How To Increase Penile Girth With Natural Methods

Do Women Prefer Girth or Length? The Absolute Truth

Do Women Prefer Girth or Length? The Absolute Truth
{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}