

Chemicals in plastics alter the brains of baby boys, making them “more feminine” - notsony
http://news.bbc.co.uk/2/hi/health/8361863.stm

======
stenl
It annoys me when news stories don't link to their sources. Here it is:
[http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2605.2009....](http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2605.2009.01019.x/abstract)

The study is terrible. All the reported effects include 0 well within the 95%
confidence interval (e.g. ranges like -2.3 to +3.2), yet mysteriously the P
values end up just the right side of "significant". This reeks of confirmation
bias, or worse.

~~~
stdbrouw
Well, no, there are a couple of intervals that don't include 0 and those are
the ones they report.

Other than that, this does look like a pretty poor study. They do that classic
(but misguided) thing where they say that their study was conducted on a small
sample and so the fact that they found anything at all is super-duper-extra
telling. In reality, it just makes it more likely that any effect that is
reported will be exaggerated – as was brilliantly pointed out by Andrew Gelman
and John Carlin in
[http://www.stat.columbia.edu/~gelman/research/published/retr...](http://www.stat.columbia.edu/~gelman/research/published/retropower_final.pdf).

~~~
carbocation
Accounting for multiple testing by Bonferroni, none of the results is
significant (at least, none reported in the abstract).

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Red_Tarsius
The experiment:

 _The women, who gave birth to 74 boys and 71 girls, were followed up when
their children were aged four to seven and asked about the toys the youngsters
played with and the games they enjoyed._

The result:

 _They found that two phthalates DEHP and DBP can affect play behaviour. Boys
exposed to high levels of these in the womb were less likely than other boys
to play with cars, trains and guns or engage in "rougher" games like
playfighting._

    
    
      DEHP - used to make PVC soft and pliable, used in products like flooring
    
      DBP - used as a plasticiser in glues, dyes and textiles
    
    

I recently read an article on a similar topic:
[https://medium.com/@GregDowney1/plastics-tiny-penises-and-
hu...](https://medium.com/@GregDowney1/plastics-tiny-penises-and-human-
evolution-6424e217df68)

~~~
notsony
On the other hand...

> _Porn and video game addiction are leading to 'masculinity crisis', says
> Stanford prison experiment psychologist_

[http://www.independent.co.uk/news/science/porn-and-video-
gam...](http://www.independent.co.uk/news/science/porn-and-video-game-
addiction-are-leading-to-masculinity-crisis-says-stanford-prison-experiment-
psychologist-10238211.html)

~~~
jfnjewkf
That's probably the worst article that I've read in the last year.

~~~
notsony
Meanwhile the opposite from another psychologist:

> _Research on exposure to television and movie violence suggests that playing
> violent video games will increase aggressive behavior. A meta-analytic
> review of the video-game research literature reveals that violent video
> games increase aggressive behavior in children and young adults.
> Experimental and nonexperimental studies with males and females in
> laboratory and field settings support this conclusion. Analyses also reveal
> that exposure to violent video games increases physiological arousal and
> aggression-related thoughts and feelings. Playing violent video games also
> decreases prosocial behavior._

[http://pss.sagepub.com/content/12/5/353.abstract](http://pss.sagepub.com/content/12/5/353.abstract)

~~~
A_COMPUTER
Even exposure to a even just a picture of a gun may cause an increase in
aggression:

[https://en.wikipedia.org/wiki/Weapons_effect](https://en.wikipedia.org/wiki/Weapons_effect)

I have wondered, assuming the effect is real, if the "problem" of media
causing violence is even socially solvable if we are psychologically this
sensitive.

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seanp2k2
Related re: BPA / estrogen:
[http://m.toxsci.oxfordjournals.org/content/114/1/1.full](http://m.toxsci.oxfordjournals.org/content/114/1/1.full)

~~~
dghughes
BPA was replaced but the alternative is just as bad.

By the way BPA is still in the thermal paper used for cash register receipts.

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y-satellite
Should probably be marked in the headline that this is from 2009.

------
striking
I'd really prefer a link to the actual study or paper, because this sounds a
little... biased, to say the least. More specifically, it sounds like the
whole "Bisphenol A" thing [1] and from even before that, the "soy mimics
estrogen" thing [2].

There's nothing new under the sun.

1:
[http://www.fda.gov/newsevents/publichealthfocus/ucm064437.ht...](http://www.fda.gov/newsevents/publichealthfocus/ucm064437.htm#current)

2: [http://well.blogs.nytimes.com/2013/09/27/ask-well-is-it-
safe...](http://well.blogs.nytimes.com/2013/09/27/ask-well-is-it-safe-to-eat-
soy/)

------
jasonkostempski
I've never heard a single thing about concerns over PVC until today. Before I
even saw this article on HN I was in the process of researching it because a
friend brought up how their dad told them not to drink the water from their
faucet because it's running through PVC. I'm in the process of buying a house
that has new PVC all over and I can't find any reliable info on this concern.
Does anyone here have any sources to share?

~~~
lucaspiller
Most new water pipes in cities are made from PVC, so it's not just what your
house is made from you need to think about. I expect you could also find
articles talking about metal leaching into water being bad too. Short of
distilling your own water I don't know what you can really do.

~~~
spacemanmatt
You can get a reverse-osmosis water filter. Mine fits under my kitchen sink. I
love it.

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fithisux
So, you mean that in ancient Rome/Greece people used plastics?

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acjohnson55
I find a small part of me wondering if this wouldn't actually be kind of a win
for humanity.

~~~
voidlogic
Wow, can you imagine the reaction you would get if you made the reverse
suggestion? You are making so many assumptions- here is something to challenge
your beliefs:
[http://www.ncbi.nlm.nih.gov/pubmed/19997098?dopt=Abstract&ho...](http://www.ncbi.nlm.nih.gov/pubmed/19997098?dopt=Abstract&holding=npg)

~~~
acjohnson55
How many assumptions can I possibly exhibit in a one-sentence comment? It
seems to me you're assuming a lot about my assumptions and beliefs.

I appreciate the link though, that's pretty interesting.

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imissmyjuno
> Girls' play

So a lack masculinity is equal to femininity? Yay gender binaries

