9 ms·

Chemicals in plastics alter the brains of baby boys, making them “more feminine”

57 points by notsony 11y ago

stenl 11y ago
It annoys me when news stories don't link to their sources. Here it is: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2605.2009.01019.x/abstract http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2605.2009.... 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.
- refurb 11y ago
  I'm glad someone looked up the actual paper. Not surprising that the findings were weak.
- stdbrouw 11y ago
  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/retropower_final.pdf http://www.stat.columbia.edu/~gelman/research/published/retr....
  - carbocation 11y ago
    Accounting for multiple testing by Bonferroni, none of the results is significant (at least, none reported in the abstract).
- rcthompson 11y ago
  And since they're doing multiple tests, 0.05 isn't even a stringent enough threshold: https://xkcd.com/882/ https://xkcd.com/882/
  - chimeracoder 11y ago
    Actually, it's worse than that - theoretically, they should be doing an F-test, but those are essentially useless[0] except as exercises for unfortunate undergraduates. This gets into the flaws with hypothesis testing (and p-values) as a tool altogether, though. And while I would love to see the natural sciences eschew these rather rudimentary heuristics in favor of the more sophisticated modeling tools that we already have, I'm not holding my breath on that happening anytime soon. [0] http://andrewgelman.com/2009/05/18/noooooooooooooo/ http://andrewgelman.com/2009/05/18/noooooooooooooo/
- formulaT 11y ago
  I couldn't see the article, only the abstract. But what they report in the abstract is some regression coefficients for a "masculinity score" and associated p-values. A very simple analysis, and not much that can go wrong there. My only concern is with cherry picking the chemicals. It wasn't clear if they were only reporting specific chemicals that had significant relationships, or if all the chemicals that would be expected to have a significant relationship did.
striking 11y ago
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.htm#current http://www.fda.gov/newsevents/publichealthfocus/ucm064437.ht... 2: http://well.blogs.nytimes.com/2013/09/27/ask-well-is-it-safe-to-eat-soy/ http://well.blogs.nytimes.com/2013/09/27/ask-well-is-it-safe...
Red_Tarsius 11y ago
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-human-evolution-6424e217df68 https://medium.com/@GregDowney1/plastics-tiny-penises-and-hu...
- notsony 11y ago
  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-game-addiction-are-leading-to-masculinity-crisis-says-stanford-prison-experiment-psychologist-10238211.html http://www.independent.co.uk/news/science/porn-and-video-gam...
  - jfnjewkf 11y ago
    That's probably the worst article that I've read in the last year.
    - notsony 11y ago
      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
deleted 11y ago
[deleted]
le_lenny_face 11y ago
The same thing happened in Taiwan several years ago, where the combination of plastics and boiling hot water used in milk feeding bottles for babies caused the male testicle size to literally shrink in diameter over the years.
acjohnson55 11y ago
I find a small part of me wondering if this wouldn't actually be kind of a win for humanity.
- voidlogic 11y ago
  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&holding=npg http://www.ncbi.nlm.nih.gov/pubmed/19997098?dopt=Abstract&ho...
  - acjohnson55 11y ago
    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.
  - cpncrunch 11y ago
    The article itself talks about less "playfighting" so it's not exactly an "assumption" of the OP. Perhaps it's an assumption of this study.
  - deleted 11y ago
    [deleted]
- ffn 11y ago
  The term feminisation as used in the article title is actually not what you think it is. I'm not in your head, but I would guess you're associating feminisation with being nicer, less aggressive, less violent, less hateful, more loving, more caring, prettier, and other such positive things (which incidentally are more associated with oxytocin than the xenoestrogens, bpas, and whatnot that they're talking about), but here, feminisation strictly means a hormonal imbalance. You can argue the accuracy and the validity of the science all you want, but the observed effects of this so-called "feminisation" is penis-related birth defects for boys and earlier puberty + menopause for girls. You are, of course, entitled to your own opinions and views on this matter, but as a man, I personally would prefer to have as large and functional penis as naturally possible.
jasonkostempski 11y ago
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 11y ago
  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 11y ago
    You can get a reverse-osmosis water filter. Mine fits under my kitchen sink. I love it.
seanp2k2 11y ago
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 11y ago
  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.
y-satellite 11y ago
Should probably be marked in the headline that this is from 2009.
imissmyjuno 11y ago
> Girls' play So a lack masculinity is equal to femininity? Yay gender binaries
fithisux 11y ago
So, you mean that in ancient Rome/Greece people used plastics?

57 points by notsony 11y ago

stenl 11y ago

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

refurb 11y ago
I'm glad someone looked up the actual paper. Not surprising that the findings were weak.
stdbrouw 11y ago
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/retropower_final.pdf http://www.stat.columbia.edu/~gelman/research/published/retr....
- carbocation 11y ago
  Accounting for multiple testing by Bonferroni, none of the results is significant (at least, none reported in the abstract).
rcthompson 11y ago
And since they're doing multiple tests, 0.05 isn't even a stringent enough threshold: https://xkcd.com/882/ https://xkcd.com/882/
- chimeracoder 11y ago
  Actually, it's worse than that - theoretically, they should be doing an F-test, but those are essentially useless[0] except as exercises for unfortunate undergraduates. This gets into the flaws with hypothesis testing (and p-values) as a tool altogether, though. And while I would love to see the natural sciences eschew these rather rudimentary heuristics in favor of the more sophisticated modeling tools that we already have, I'm not holding my breath on that happening anytime soon. [0] http://andrewgelman.com/2009/05/18/noooooooooooooo/ http://andrewgelman.com/2009/05/18/noooooooooooooo/
formulaT 11y ago
I couldn't see the article, only the abstract. But what they report in the abstract is some regression coefficients for a "masculinity score" and associated p-values. A very simple analysis, and not much that can go wrong there. My only concern is with cherry picking the chemicals. It wasn't clear if they were only reporting specific chemicals that had significant relationships, or if all the chemicals that would be expected to have a significant relationship did.

striking 11y ago

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.htm#current http://www.fda.gov/newsevents/publichealthfocus/ucm064437.ht... 2: http://well.blogs.nytimes.com/2013/09/27/ask-well-is-it-safe-to-eat-soy/ http://well.blogs.nytimes.com/2013/09/27/ask-well-is-it-safe...

Red_Tarsius 11y ago

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-human-evolution-6424e217df68 https://medium.com/@GregDowney1/plastics-tiny-penises-and-hu...

notsony 11y ago
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-game-addiction-are-leading-to-masculinity-crisis-says-stanford-prison-experiment-psychologist-10238211.html http://www.independent.co.uk/news/science/porn-and-video-gam...
- jfnjewkf 11y ago
  That's probably the worst article that I've read in the last year.
  - notsony 11y ago
    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

deleted 11y ago

[deleted]

le_lenny_face 11y ago

The same thing happened in Taiwan several years ago, where the combination of plastics and boiling hot water used in milk feeding bottles for babies caused the male testicle size to literally shrink in diameter over the years.

acjohnson55 11y ago

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

voidlogic 11y ago
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&holding=npg http://www.ncbi.nlm.nih.gov/pubmed/19997098?dopt=Abstract&ho...
- acjohnson55 11y ago
  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.
- cpncrunch 11y ago
  The article itself talks about less "playfighting" so it's not exactly an "assumption" of the OP. Perhaps it's an assumption of this study.
- deleted 11y ago
  [deleted]
ffn 11y ago
The term feminisation as used in the article title is actually not what you think it is. I'm not in your head, but I would guess you're associating feminisation with being nicer, less aggressive, less violent, less hateful, more loving, more caring, prettier, and other such positive things (which incidentally are more associated with oxytocin than the xenoestrogens, bpas, and whatnot that they're talking about), but here, feminisation strictly means a hormonal imbalance. You can argue the accuracy and the validity of the science all you want, but the observed effects of this so-called "feminisation" is penis-related birth defects for boys and earlier puberty + menopause for girls. You are, of course, entitled to your own opinions and views on this matter, but as a man, I personally would prefer to have as large and functional penis as naturally possible.

jasonkostempski 11y ago

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 11y ago
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 11y ago
  You can get a reverse-osmosis water filter. Mine fits under my kitchen sink. I love it.

seanp2k2 11y ago

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 11y ago
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.

y-satellite 11y ago

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

imissmyjuno 11y ago

> Girls' play So a lack masculinity is equal to femininity? Yay gender binaries

fithisux 11y ago

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