We, here at SciShow, don’t need  to tell you that science has led   to the discovery of some pretty worrying facts.

Sea levels really are rising,  pandemics really do happen,   and Valve still doesn't have a  release date for Half Life 3. But sometimes, those shocking headlines don’t  really match what the researchers actually said.

The media grapevine can take a normal paper with   appropriate caveats and turn  into an unmitigated shocker. Not SciShow though. We’re cool, I promise.

While there, of course, are some  real, concerning things happening in   the world right now, not every scary  science headline is what it seems. If you’re watching this video, you probably  love some critical thinking about good science,   so sit back, relax, and let  us put your mind at ease. [♪ INTRO] So, first of all, you might have heard that a  spoonful of sugar helps the medicine go down. But have you heard that there’s a  spoonful of microplastics in your brain?

If you have, there’s a good chance that that  news didn’t make you want to bust out into song. A team of US researchers set out to find how much  microplastic was making its way into our organs. They got liver, kidney, and brain samples from  cadavers and used a method called Py-GC/MS.

Basically, they used chemicals to dissolve  all of the organic tissues in the sample,   which left behind any inorganic  solids that they could measure. And the researchers found that  people who died in 2024 had nearly   1.5 times more microplastic in their  brain than those who died in 2016. The samples from 2024 had almost 5000 micrograms  of microplastic per gram of brain tissue.

Which, if you take the average mass  of a human brain as 1300 grams,   that’s 6.5 grams of plastic just in your brain. Or, about the mass of a plastic takeout spoon. That’s bad news bears for you if your  preferred amount of brain plastic is zero.

And that is my preferred amount of brain plastic. That’s the amount there should be. Fortunately for us, some other researchers  have reason to believe that we don’t actually   have as much plastic clattering around  up there as the initial study suggests.

Their critique has to do with methodology. Py-GC/MS is known to overestimate  the amount of plastic in tissues. And our environment has a lot of plastics already,   so even in a high quality lab environment, that  has the potential to contaminate the process.

Secondly, the process of performing Py-GC/MS  can create byproducts that mimic microplastics. For instance, fat molecules release some  of the same compounds that polyethylene   plastic does during Py-GC/MS, and  the brain tissue is about 50% fat. So some of the compounds that were reported to be  microplastics might have been just normal old fat.

Plus, the researchers only looked at about 50  brains total, which isn’t a huge sample size. Like, some would argue that that is too  small to draw meaningful conclusions from. And all this said, we’re not even sure what  the health implications of brain plastic are.

Even though it’s hard to imagine it would  be good for you, we simply don’t know if   microplastics cause health problems  or are just associated with them.’ And I feel like if there were a whole plastic   spoon of microplastic in my  brain, I would have noticed. I just feel like I would have noticed. Also, while we’re at it,   you are definitely not eating a credit  card’s worth of plastic every week.

I did a video about this a couple of years ago, in  case you are into being un-scared about plastic. And if you’re super into being un-scared  about plastic, we’ve got another one for ya. Another recent scary plastic-based  headline isn’t about your brain.

It’s in your kitchen. There was a recent hullabaloo about  how black plastic cooking utensils   like spatulas and stuff might contain  dangerous amounts of flame retardants. And I don’t know about you, but my grandma’s  secret ingredient was love, not flame retardants.

The flame retardant that people  are specifically concerned about   is called decabromodiphenyl ether, or decaBDE. DecaBDE was found to be possibly bad for humans,  so the US Environmental Protection Agency started   banning its use in 2009 and completely banned  its manufacturing and distribution since 2021. However, sometimes it can still show up in black  plastic items due to manufacturing quirks.

See, the EPA didn’t ban the recycling  of plastic products with decaBDE,   because they calculated that any plastic  that already contained it had it at such   low amounts that it would be super  unlikely to cause any health issues. But a group of scientists from an organization  called Toxic Free Future wanted to confirm that,   so they analyzed 203 black plastic  household products for flame retardants,   and more specifically,  bromine, which is in decaBDE. Out of those 203 items, the researchers narrowed   down the top 20 plastic products  with the most bromine in them.

These included toys and hair accessories,   but they were mostly concerned with  contamination you could possibly ingest. Looking at you, kids, putting that  black plastic toy car in your mouth. But this is why you really only heard about  this in relation to your cooking utensils.

The researchers calculated that  black plastic utensils may be   leaching about 35,000 nanograms  of decaBDE into your food per day. The EPA says the safe limit for decaBDE exposure  is 7,000 nanograms per kilogram of body weight,   which the authors of this study calculated   to be 42,000 nanograms per day  for an adult who weighs 60kg. That 35,000 nanograms from utensils sounded  way too close to the 42,000 limit for comfort,   which is why they raised this red flag.

But the mathematically-inclined members of our   audience might be screaming at their  screens right now for a good reason. The EPA limit of 7,000 nanograms  per kilogram per day, times 60 kg…. is 420,000 nanograms, not 42,000. So what actually happened here was:   A misplaced comma made the problem  seem ten times worse than it is!

There are still trace amounts of flame  retardants in those black plastic spatulas,   but the level is well under what the EPA  considers safe when you do the math correctly. So if you didn’t get around to replacing  all your black plastic utensils yet,   you can probably cross that off your list. And before we get to our next not-so-scary  headline, here is a quick ad break.

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The next story is a lot bigger  than anything in your kitchen. Like, the size of your planet’s atmosphere. If you were tuned into the news any  time between the 1980s and the 2010s,   you probably heard a lot about  that hole in the ozone layer,   which is really less of a hole  and more of, like, a thin spot.

The ozone is a protective layer of gas around the   Earth that shields us from  harmful solar radiation. So when there’s a thin patch in  the ozone, we get less protection,   and all living things are at risk of, like,  DNA damage and also really gnarly sunburns. Scientists found that a major driver of ozone  depletion was chlorofluorocarbons, or CFCs.

These chemicals used to be super common  in household products like refrigerators,   and in aerosols like hair spray. But welcome to the 2010s, when CFCs had to go. They were banned by an international  treaty called the Montreal Protocol,   after which the entire world  phased out products with CFCs.

Hooray, problem solved! However, in 2018, you might have heard about  this, some scientists found that the levels   of CFCs in the atmosphere weren’t  dropping as quickly as they should,   indicating that there were some  renegades still making these CFCs. The researchers traced the secret CFCs  to a few factories in eastern China,   and thanks to international cooperation  between scientists and Chinese authorities,   the factories were shut down and  the ozone is again back on the mend.

So now the ozone hole is on track to  be fully healed within a few decades. You can’t stop the motion of  the ocean or the sun in the sky,   but you can stop our hairspray  from hurting the planet. And if you’re like me, all you heard  was that CFCs were going up again.

You didn’t hear about the part where  we noticed and did something about it. Now, our next scary headline  to debunk is about your diet. Intermittent fasting is a popular diet pattern   that is mostly defined by  the times you are eating.

Usually, you’d spend around 16 hours not eating,   then eat all your daily nutrition  in the remaining 8 hour window. This sounds terrible to me. Lots of people choose intermittent  fasting for a variety of reasons   including losing weight and a whole  slew of other alleged health benefits,   although the evidence behind  how well it works is….mixed.

So it might be shocking to hear that, according  to a conference presentation at the American Heart   Association, intermittent fasting was associated  with a 91% higher risk of cardiovascular death! And at first glance, this looked  like really solid science. The American Heart Association is a  reputable professional association,   and the study looked at over 20,000 participants.

The important part here, though,   is that this data was presented at a  conference as preliminary research. That means the work hadn’t been peer  reviewed or formally published yet. And for those that read past the headline,   the authors were clear that the  findings came with a few caveats.

First of all, the participants’ diets were  classified as either intermittent fasting or not,   based on their own recollection  of when and how much they ate,   and they only recorded two days of meals. It’s possible some of these people just had, like,   a weird eating pattern for a couple days, and are  not all-in on the Intermittent Fasting lifestyle. It’s also very easy to forget what  you ate for breakfast two days ago,   much less at what specific amounts or  exactly which hours you started and stopped,   which is why self-reporting data needs  to be taken with a hefty grain of salt.

Plus, this study looked at association  with cardiovascular disease, not causation. There were a few things that weren’t accounted  for, including the fact that people who try   intermittent fasting may already have other  risk factors for cardiovascular disease,   such as obesity, that may be  motivating them to try the diet. Some other studies have suggested that  intermittent fasting is actually good   for your heart, as a side effect of losing weight.

But even then, experts aren’t 100% convinced  that intermittent fasting is the way to go. Clearly, the research is mixed on this and  we need to wait for more research to be done. So whether you’re team intermittent  fasting or more of an all-day grazer,   we really can’t say for sure if any mealtime  patterns are going to mess with your heart.

Hopefully that helps settle your stomach a bit. Now, our last entry in our list is also about  our health, but it does not have to do with food. This time, the threat identified  by scary headlines was tampons.

A 2024 study looked at a variety of tampon brands  and types and found that they contained traces of   16 different heavy metals, including  arsenic, cadmium, mercury, and lead. And that’s especially bad when you  think about where those tampons go. Arsenic is a well-known poison,   and we’re rightfully hammered over  the head about the dangers of lead.

And given that tampons are only relevant to people  who have periods, discovering secret metals may   feed into current biases that you may have that  menstrual health is undervalued and understudied. Which, honestly, can’t blame anybody there. But before you purge your bathroom  cabinet and switch to diva cups,   you should know that most of these  metals were in trace amounts.

Like, billionths of a gram. The metals that they found in the highest  amounts were zinc, with an average of 52   micrograms, calcium, with an average of 39  micrograms, and iron, around 3 micrograms. And you eat thousands of times more  than all of those in your daily diet.

That said, we’ve only ever really studied  exposure to these heavy metals through the   oral route, so we don’t know for  sure if the amounts that we know   are safe to have in food are equal to  the safe amounts in period products. Even for the metals like lead, for which  there is no safe amount of exposure,   the researchers didn’t look at how much can  actually get absorbed into the body from a tampon. Which means it’s possible that we just  don’t absorb any lead through that route.

But you might be asking:   How are these heavy metals getting  into the tampons in the first place? And, probably, it is from the  plant materials in the tampons. Plant-based fibers like cotton and rayon are often  naturally exposed to metals in the environment,   and those metals can get sucked up  through the soil into the plant.

This study was also a broad  overview, not a deep dive. The researchers only sampled 1-2  tampons per brand and absorbency type,   which is not a big enough sample  size to say anything definitive. Still, everyone deserves to be safe  from heavy metal contamination,   so it’s definitely worth  further research to make sure.

In the US, tampons are regulated by the FDA,  and after the original study was published,   the FDA launched a lab study of  their own in late 2024 to follow up. And they found…. Nothing.

So far, the folks over at the FDA say there’s   no reason to panic and throw  out perfectly good tampons. And really, isn’t this what science is all about? We are surrounded, on all sides, by people  expanding human knowledge in exciting ways.

Sometimes that knowledge is excitingly  positive, but sometimes, a tiny claim that   comes with nuance and caveats gets blown  up into a definitive, splashy statement. And that can cause panic or feed into  upsetting storylines that just aren’t true. Of course, not every shocking science headline  is wrong, but they get their excitement from   being new, and science always requires  repeated trials and further validation.

After all, the information that is the most  surprising is what’s going to get you the clicks. The stories we talked about today aren’t examples  of science going wrong, or being unreliable. Science moves forward when researchers present  new ideas to the public and other scientists,   for other studies to investigate and verify.

But we hope that presenting a  more balanced way of interpreting   scary-sounding headlines can put your mind  at ease, and prevent some undue panic. So the next time the news is telling you  to throw away your favorite cooking spoons,   maybe just keep them in a drawer  until the other researchers weigh in. [♪ OUTRO]