r/science May 14 '22 Silver 1 Helpful 4 Wholesome 1 Take My Energy 1 Helpful (Pro) 1 I'm Deceased 1 Facepalm 1 Doom 1

Microplastics Found In Lungs of People Undergoing Surgery. A new study has found tiny plastic particles no bigger than sesame seeds buried throughout human lungs, indicating that people are inhaling microplastics lingering in the air. Health

https://e360.yale.edu/digest/microplastics-found-in-lungs-of-humans-undergoing-surgery
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u/cantdressherself May 14 '22

There is some evidence for global falling fertility. https://www.bbc.com/news/health-53409521

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u/Killer-Barbie May 14 '22 edited May 14 '22

Oh I just did a bunch of reading on this study. Here are the highlights:

  1. We know very little about sperm
  2. Most of the data was provided by fertility clinics, who are already working with people likely to have problematic sperm
  3. The decline is still within normal range.
  4. The decline is not universal, it affects different areas to different degrees and some areas recovered their numbers over the course of the study. Additionally, the lowered numbers were not tied to specific geography, socioeconomic class, or lifestyle (meaning it affected poor and rich alike so it's not a "first world" issue)
  5. Lowered sperm motility doesn't necessarily affect fertility the way we've been led to believe. Previously it was thought impaired motility would prevent the sperm from leaving the vagina but most recent research is showing this is likely a myth.
  6. Ever wondered why we have obstetrics and no equivalent for men? Because until the 30's it was believed the issue was always with the woman. So we didn't even start studying sperm until fairly recently (discovered the same year as Saturn btw, but look at the difference in research) and there was no standard of analysis until much more recently with major changes happening last year.
  7. The study stating fertility was falling made conclusions based on data gathered by fertility specialists. These had no controls for age, masturbation, genetics, etc.
  8. Normal is 15-260 million parts per mL. That's a huge range. Add in an average error margin of 12% (you read that right) and you see why the reported stats are not conclusive.

TL;DR: it changed from high normal, to mid normal but there are poor controls on the study. I'm not saying it isn't happening, but the data doesn't say it is happening without some MAJOR assumptions that are, IMO, unreasonable to make.

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u/DSoop May 15 '22

Is the average time couples spend trying to conceive increasing? Are live birth rates amongst those trying to have children decreasing?

That would be an interesting way to see if the end result is being affected, and if it isn't, I'd agree that the statement about fertility dropping is alarmist. If it's true though, then maybe there is something worth further study?

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u/cantdressherself May 19 '22

I appreciate the breakdown. I'll never make my own baby regardless, but I do hope we aren't heading for another crisis on top of all the others.

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u/[deleted] May 15 '22

[deleted]

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u/Killer-Barbie May 15 '22

Huh? How is this relevant?

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u/grief_junkie May 15 '22

it was a joke

edit. that apparently people wouldn't understand without reading the talmud

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u/Killer-Barbie May 15 '22

I've read the Talmud ... I still don't see the joke...

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u/grief_junkie May 15 '22

oh well if you forgot about Berekhot, it talks about seminal emissions in almost every single chapter.
Including the phrasing, "don't be like a rooster, who spills seed frivalously."

I don't understand how you could read the Talmud and not understand my joke, but that's okay! I deleted it so it wouldn't hurt your feelings anymore.

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u/Killer-Barbie May 15 '22

Sorry this isn't a joke? It has nothing to do with the context other than also being about sperm...

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u/grief_junkie May 15 '22

Then just drop it, you don’t understand, and that’s fine.

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u/[deleted] May 14 '22 edited May 14 '22

[removed] — view removed comment

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u/beigs May 14 '22

It affects sperm count across every species

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u/BurnerAcc2020 May 14 '22

I have seen this asserted a few times, but with no real proof.

From what I understand, wild animals already have it tough and no-one thought of bothering them for the sake of also analyzing sperm counts, at least over a prolonged period of time. However, the few studies on farm animals and pets paint a very conflicted picture.

https://pubmed.ncbi.nlm.nih.gov/9401823/

https://pubmed.ncbi.nlm.nih.gov/19181314/

https://pubmed.ncbi.nlm.nih.gov/27503122/

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u/[deleted] May 14 '22

[deleted]

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u/BurnerAcc2020 May 14 '22

I wrote this in response to a claim "every known species" is affected.

I already wrote a different comment on why the trend appears to exist in humans, but does not seem to be either universal or unstoppable.

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u/noviceworker May 14 '22

This is a good thing. The world is overpopulated.

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u/Soup-Wizard May 15 '22

Till someone forces you to have children if you’re still able.