Justin: Good morning Kirsten.
Kirsten: Good morning Justin. Have a good weekend?
Justin: Yes.
Kirsten: Awesome. We’re back, this is This Week In Science, it’s 8:30 in the morning on Tuesday, the 18th of September. Welcome, welcome, welcome to all you listening out there. We’ve got a lot of Science right?
Justin: Big week in science News. My goodness.
Kirsten: Actually, I thought last week was bigger.
Justin: This week is the biggest I’ve ever seen.
Kirsten: Ever.
Justin: Ever.
Kirsten: We have an interview at the top of the hour, the 9 o’clock.
Justin: The biggest interview we’ve ever had on this show.
Kirsten: Ever.
Justin: Ever.
Kirsten: Well that might be next week. I’ll see what I can do about that but…
Justin: Why are you guys – we have an invited guest today, no. Today’s show.
Kirsten: You got to tease for next week too.
Justin: Oh, yes right.
Kirsten: Okay, today…
Justin: But next week will be even bigger but your mind won’t be blown with how much bigger it could be unless you’ve listened to this show.
Kirsten: Right. We are going to be speaking with Dr. Rolf Halden, assistant professor in the Department of Environmental Health Sciences at Johns Hopkins Bloomberg School of Public Health. He studies Toxicology basically and there’s a lot of stuff in our environment that we need to be aware of, things that are going into products through the chemical industry that go through those products.
Justin: And then through our systems.
Kirsten: Yes.
Justin: Biologically (unintelligible).
Kirsten: Into water, into agricultural use, into plants, animals, into us.
Justin: Into us.
Kirsten: And how is that affecting us? We’re basically going to be talking with him about a compound called – two compounds Triclosan and Trichlocarbon.
Justin: Yum.
Kirsten: Yes, these are compounds that are commonly put into anti-bacterial soaps.
Justin: Which is great because I think we’ve just left…
Kirsten: This is necessarily good for you.
Justin: …like national hand washing week.
Kirsten: Yes.
Justin: That was like last week.
Kirsten: National hand washing week and…
Justin: And I’m a little bit themed up for that today, actually. I’m all about hand washing today.
Kirsten: We like…
Justin: And I’ve got a lot of stories…
Kirsten: That’s a good thing because there’s an issue with men washing their hands.
Justin: That’s my story, I got that one. They brought that one.
Kirsten: I’ve got some brain stories. We’ve also… I also have a hole in the Arctic story.
Justin: Yes, I don’t know, should we go with the hole in the Arctic? I’ve also got one about bubble gum that doesn’t stick to your shoe. I don’t know, what’s more important these days?
Kirsten: What’s bigger?
Justin: I don’t know. It’s getting hard to decide.
Kirsten: Yeah. If you’d like to join us for the next half hour, 752-2777 is our phone number, www.twis.org or thisweekinscience.com. If you want to join us online in our forums and… let’s get started.
Justin: Are we answering the question about what happens when you fall through the planet earth?
Kirsten: No, I’m going to give that one more week.
Justin: One more week, okay.
Kirsten: I got two responses from people this week. And one of them I can’t open because it’s in Linux and I’m not going to open it.
Justin: I’m getting close, I’m getting close.
Kirsten: I am fortunately…
Justin: I almost forgot it figured out.
Kirsten: I know how much people who use Linux love unit Linux, and how they think it’s superior but I just…I haven’t gotten there yet. I’m sorry I have to say I’ve just stayed with the same band.
Justin: But here’s the thing the email in here Kirsten, the question is what happens if you can create a hole from one end of the earth to the other right down the center…
Kirsten: Yes.
Justin: …and it’s insulated so there won’t be any temperature variances. And it’s slick so that if you rub along the side you won’t catch yourself on fire.
Kirsten: Yes.
Justin: If you fall into this hole what happens? Do you just go to the middle and stop? Do you go to the middle and explode?
Kirsten: Are you crashed? Are you exploded?
Justin: Zip out the other side and get projected out towards the middle.
Kirsten: Right.
Justin: What happens?
Kirsten: What happens?
Justin: So, that’s the question.
Kirsten: What happens to you when you get to the center of the earth?
Justin: And apparently the air pressure is the same, which at first didn’t make any sense to me.
Kirsten: Well it’s just, it’s a hypothetical question.
Justin: You don’t have actually more air, more atmosphere on top of you as you go down really than you do on the surface here. That actually make sense now. That one I grappled with.
Kirsten: You would have more.
Justin: No, very little more. Just that the tube’s worth more. That’s why…
Kirsten: No, he was just saying it’s not even part of the equation.
Justin: It is, is it because…
Kirsten: No. It’s not even part of the equation. Not even for any logical reason. It’s just to take it out of the equation.
Justin: For the logical, that’s one for the logical reason because you don’t really have more atmosphere at… on top of you. It didn’t make sense at first, and now it does.
Kirsten: But you do.
Justin: No you don’t.
Kirsten: Yes, you do.
Justin: It’s no, because it’s just the tubes worth.
Kirsten: If you are at the center of the earth? No.
Justin: If you went down the tube…
Kirsten: To the center of the earth.
Justin: …if the tubes worth of atmosphere more above you…
Kirsten: Justin, you’re wrong.
Justin: I’m not wrong. I’m not wrong.
Kirsten: You are.
Justin: It didn’t make sense at first, now I get it because there’s not really more atmosphere on top of you. Unless you got rid of all the earth and put more atmosphere in there, then the pressure would go up.
Kirsten: You’re thinking about it in the wrong way. We’ll talk about it after the show.
Justin: Okay, stories, stories lots of stories.
Kirsten: I like the idea of talking about men today. Let’s talk about men.
Justin: Oh my goodness. Okay this is here I’ve got – this has got one of those preambley titlely things that leads into the story, where is that? Here we go. Ready for work now, finally.
Healthy hygiene hand washing habit found habitual in the hers hibernating in the his. Observational study finds 66% of men don’t wash hands in public restrooms, 88% of women do. So, the girls definitely…
Kirsten: And the number for men has been decreasing. That’s the problem.
Justin: Yes we’ve been back-sliding a little bit.
Kirsten: Why have man been back-sliding? Men are stubborn, is that it?
Justin: Wait a minute, lights flashing…Good morning, TWIS minion you’re on the air with This Week in Science.
Man: Yes.
Kirsten: Hello.
Man: Hi. Am I on the air?
Kirsten: You are on the air.
Justin: Yes. You’re live on the air, in front of tens of thousands of people.
Man: Look, Justin?
Justin: Yes.
Man: Listen to the woman. The pressure would crush you, even if its the size of a little tube. If the air is connected, the pressure would crush you. It doesn’t matter what the section is, it matters that the pressure will be, much higher.
Kirsten: Yes, it’s air pressure.
Man: Listen to her.
Justin: So, the air pressure is then the result of gravity?
Man: Thank you. Take care.
Kirsten: Thank you very much for calling.
Justin: Thank you for clarifying but I still don’t get it. I don’t believe it. I don’t get it yet. I just don’t. Because I understand as you go under water the pressure gets bigger and your ears hurt, and…
Kirsten: You know what?
Justin: Huh?
Kirsten: I’ll bring an answer for you.
Justin: Okay.
Kirsten: Next week when we bring other people’s answers to the hypothetical.
Justin: Yes.
Kirsten: How does that sound? I will describe, I will describe this phenomenal question.
Justin: So, in the meantime I’ll stick to my guns. Is that what you’re saying because I have no…
Kirsten: You should just be quiet.
Justin: Back to the – okay so, yes men don’t, aren’t said – they don’t wash their hands. This is my favorite part though. A separate study says that when people were asked how often they wash their hands? 92% of people said, “Yes we wash our hands after every time.”
Kirsten: How about when spies are in the bathroom?
Justin: See but then this is the alteration to the study then because this is other whole part. Because they hire these people to go stand in these public restrooms like where, Turner Field in Atlanta, Museum of Science and Industry, the Shed Aquarium, Grand Central Station in New York, Ferry Terminal in San Francisco.
Kirsten: I love it, lurkers in the bathroom, the best.
Justin: Well here’s the thing if you are in the women’s bathroom and I’m just I’ve never really hung out there but I can assume that if there’s a lady just sort of standing there, a woman will assume maybe she’s waiting for her partner, because woman go in pairs, that happens.
If you are in a men’s restroom and there’s just somebody standing there, and here’s the thing, if you’re getting hired to work on one of this surveys, chances are you’re not really one of the top-tier workers in our society. And probably your parents can also – I’m just saying if your job is to be in a bathroom counting how many people wash their hands, your attire might not look that…
Kirsten: You’re probably an undergrad or a grad student doing research course.
Justin: At best or at worst you answered an add to make $5 an hour doing surveys…
Kirsten: Right.
Justin: …in a bathroom. Okay. So, the thing is too this is another thing – I like this part too because when they went into the stadium…
Kirsten: Mm hmm.
Justin: …the stadium, the men went from 66% all the way down to 57%. And women, the women, however, that was like one of their better showings, they were 95% in the stadium. The sports are in there.
Kirsten: Right, because there are lots of people in there and it’s gross.
Justin: See that’s how the women are seeing it, right. That’s what the women are thinking. What the men are thinking is, I’m in a room of 40 guys urinating all at once. I’m more concerned with the splatter, than I am with washing my hands, I want to get out fast.
Kirsten: Get out. The psychology of it might be different. Oh my goodness! So, what’s the reason that we live as long as we do? Longevity, the age, the age mortality is increasing.
Justin: Increasing.
Kirsten: As time goes on, it’s increasing. Medical Science might be one and Technology might be one thing behind it. But it’s also, at the point where we are right now, why is it that women survive passed the age of menopause?
According to evolutionary theory there is a hypothesis that suggests that as soon as an organism is done reproducing, there’s no need for it to stick around anymore. So, why would it?
So, the grandmother hypothesis of this, the alternative hypothesis of this suggests that, women after they reached the end of their childbearing years, they stick around to be play grandmother and to help ensure the success of the later generations; ensure the success and survival of the genes that they have helped to pass on.
But the theories – the model, not the theory, the models to this point have left men out of the equation because it’s too complicated to include men. But finally some researchers…
Justin: Because men can reproduce damn near forever.
Kirsten: Forever almost, exactly. It takes much longer for men to lose their childbearing, their fertility.
Justin: Their (baby batter).
Kirsten: Exactly. And this is really interesting what they call it, they call it the wall of death, which is the point at which you end your reproductive years and you should die off. “The wall of death”, I love this.
But it turns out that just a few individuals in a society, men reproducing into their 50’s, 60’s, 70’s, 80’s, 90’s even can have a very strong effect on the population as a whole because men pass on their genes not only to the male children but the female children as well.
So, they pass on their longevity, the fact that they’ve lived as long as they have and they are surviving, and not dying from any odd causes. If men were to start having babies regularly into their 90’s, the longevity of the human race may just expand.
Justin: Well except for, and here’s the other thing the later in life that you have children, the more likely there’s going to be a chromosomal problem so, we’ll live forever. But maybe…
Kirsten: But in this study…
Justin: …we’re scared of our own shadow.
Kirsten: In this study researchers looked at hunter gatherer groups in the Dobe !Kung of the Kalahari and Ache of Paraguay. They also look at forager-farmer groups in Yanomamo of Brazil and Venezuela and the Tsimane, an indigenous group in Bolivia. No, then they looked at Canadians as their control group. Let’s go with these… and then, Canadians.
Justin: Yes.
Kirsten: In the tradish… the less developed societies men were as much as 5-to-15 years older than their female partners on average…
Justin: Is that like (rural) Ottawa?
Kirsten: Not in Canada and in a more developed country, Canada, the age difference between men and women is on average of about only two years. So, in these traditional societies that maybe even support having many wives you have one alpha male who lives, who lives to a nice old age, who’s having children…
Justin: Could you write that down?
Kirsten: What?
Justin: Where that is? The many wives.
Kirsten: No, you need to go to the Kalahari Desert, Justin.
Justin: All right.
Kirsten: Anyway it’s an interesting hypothesis that possibly it is this longevity of males that is supporting the longevity of our…
Justin: I like it.
Kirsten: …people of humanity as a whole.
Justin: Well this wall of death actually kind of goes into my next story here. Because it could be another element that’s missing from what they’re looking at here, seemingly innocent enough sounding, genomic study. Social regulation of gene expression in human leukocytes offers us a kind of crosswords of sorts that may tie into this wall of death, depending on how this research is going to progress into the future.
One direction could explain the suffering of the lonely hearted, or, if it goes the other way could send those lonely hearted already on the dark path of silent despair to a ill-fated doom that no measure of willful wanting will remove them from.
The study looked into the casual observance of the past and those…the connection between people who were alone, isolated or lonely basically having shorter life spans and having more ailments and illnesses, right?
Kirsten: Yes.
Justin: So, what they did was they compared genes between very lonely people to those who are social butterflies. And the very lonely people, I think one of the things they had to qualify was for about at least the last four years they felt like they had no significant connection to another human being. I mean this is, loneliness.
Kirsten: That feeling alone.
Justin: This is yes, isolation. What the study identified was a clear genomic fingerprint of social isolation. 209 genes stood out in the loneliest people. Here’s the thing, out of the 200 genes say, out of, what, thousands of thousands of genes in the body what’s the big deal?
The thing is this is – I’ll just read the quote “ These 200 genes weren’t sort of a random mish mash of genes they were part of a highly suspicious conspiracy of genes. A big fraction of them seemed to be involved in the basic immune response to tissue damage.
Says Steven Cole, Molecular Biologist at UCLA, “Others were involved in the production of antibodies, these genes.” So, the findings suggest that the loneliest people have unhealthy levels of chronic inflammation, associated with Heart and the Artery disease, Arthritis, Alzheimer’s and other ailments. So, the question becomes then what came first, the genetic propensity for these illnesses or the isolation?
Kirsten: Right.
Justin: Is this isolation causing a difference in the genes? Is it the sort of the wall of death, the body deciding well, we haven’t even had a shot at reproducing for a long time. Chances are we’re not going to… wall of death. Okay call it up, okay. But, or this is an indication that perhaps lonely people are somehow are being avoided based on the genetic difference like there’s something that we’re not aware of but…
Kirsten: It’s a chicken and the egg kind of question.
Justin: But there’s another one.
Kirsten: Does lonely cause it? Does the immune system cause loneliness?
Justin: Do we avoid people who have this gene difference because maybe we’ve decided they can’t be [unintelligible]? Even though we don’t know what the signs are, we couldn’t write it down.
Kirsten: But there’s something about them.
Justin: Something suddenly different that, or is it an indication of something more sinister about the human heart.
Kirsten: Why are you reaching this far?
Justin: Well actually I’m only reaching back to your story the wall of death. I was just supposing that. I didn’t know that anybody had thought of this before, that we might self-select ourselves from removal of the human hurt some sort of self sacrificing eugenic social suicide of non-participation, right? So, to achieve this genetic isolation of our deficiencies for the greater good, we just don’t date, we don’t leave the house, we become isolated and lonely. And…
Kirsten: There’s some kind of switch in our head that says…
Justin: Yes, that just says… leave.
Kirsten: You’re out.
Justin: I must not damage the…
Kirsten: Oh my goodness.
Justin: In any case this is – the study suggests that aspirin, due to its anti-inflammatory and blood thinning properties may assist with the majority of the ailments caused by this genetic variance.
Kirsten: That’s interesting.
Justin: Making the need for social suicide in the face of medical science a noble gesture that will likely go unnoticed, but then, the lonely are used to being unnoticed.
Kirsten: But, just take two aspirin and call them in the morning.
Justin: Go meet somebody, go down to the… Take yourself out to your local bookstore, not the one – not the hole in the wall one with all the used books on the wall. You go to the bright, shiny new one. You’re not there to buy a book, you’re there to look at something that’s an impressive topic something like, find, look, stare at the cooking books for a while. That’s one I think that works well on the ladies. Because they imagine that you cook, and therefore you’ll be somebody worth dating.
Kirsten: Right. Researchers have been taking a look at the brain, not related to the loneliness and whatnot, but related to intelligence and what makes the brain what it is. What makes who we are, who we are?
Justin: Selective brain damage, that’s my guess.
Kirsten: (Dan) from Portland, Oregon sent me this story. A researcher, Richard Haier of the University of California, Irvine and Rex Young of the University of New Mexico have come up with a theory called the Parieto-Frontal Integration Theory or P-FIT.
They’ve done a review of many years of brain imaging studies and they’ve identified what they call the stations along the path along which information is processed that allow us to actually be intelligent or perform behaviors which one would consider intelligent, suggests that areas related to intelligence are also related to attention, memory and some more complex functions like language, the ability to speak well.
Justin: What are you saying I’m sorry…
Kirsten: Yes, attention Mr. Attention Memory Deficit…
Justin: …you said… I was trying to find my next story here.
Kirsten: And so, a lot of what – some people think that intelligence has to do with the speed at which information is processed. So, if you have good connections and large number of connections between these information processing centers it will allow a flow of information to occur more quickly. So, this might be one other aspect…
Justin: Wrong bad thinking.
Kirsten: …P-FIT hypothesis, the P-FIT theory. What they basically think is that intelligence can be inherited and since genes work through Biology, there must be a biological basis for intelligence, so, what is it and what are the structures that determine it and how are they organized to allow us to be smart?
To answer this question, researchers from the Salk Institute for Biological Studies and the Telethon Institute of Genetics and Medicine in Italy report in Nature Neuroscience this week that there’s a gene, a factor called COUP-TF1, and this factor, this gene ensures that the frontal areas of the brain don’t get too big and squeeze out the sensory areas of the brain.
There’s a fine balance between the information processing centers for attention in the front of the brain, frontal region and the sensory areas like the visual cortex and the back of the parietal cortex, all of this somatosensory cortex that allows us to sense motion of our body and to initiate motion.
Justin: So, when the day comes and I want to go in and do a makeover of my brain in the future…
Kirsten: That’s right.
Justin: I’m going to be like…well I like my vision I’m going to keep that. I don’t really need the sense of smell or sense of taste.
Kirsten: No, I think I ought to get rid of them. That’s all right.
Justin: I’d take some more intelligence to push those senses just completely off the map.
Kirsten: Right. They tried genetically engineering mice to lack COUP-TF1 but they all died. So, then what they did is they got their mice to start developing and then they started selectively removing COUP-TF1 from cells in the cortex that turned into the sort of progenitor cells that lead into the frontal cortex or the visual cortex, whatever.
They got them selectively removed to stop COUP-TF1 from appearing. They say the mice survived into adulthood and they appeared to be fairly normal, although they don’t think they are.
Justin: Again, we won’t know until we teach mice to speak what the social ramification…
Kirsten: Right.
Justin: …of any of these researches are.
Kirsten: The result of the removal of COUP-TF1 from these mice is that the frontal areas did take over most of the cortex. And the sensory regions were reduced in size and relegated to an area in the very back of the brain.
Justin: Did they function?
Kirsten: They are still functioning.
Justin: Wow, so, I can be smarter ants and still be able to smell my coffee in the morning.
Kirsten: Might not smell very well though. They didn’t do those behavior tests.
Justin: I can get rid of it. I don’t even need it.
Kirsten: So, there are two genes now that are known EMX2 and this new one COUP-TF1 and they work in opposing ways. So, that EMX2 works to specify the area that visual neurons take up. COUP-TF1 prevents progenitor cells from taking on a motor area identity.
So, one of them ensures that it’s a sensory neuron and the other one ensures that it’s not going to turn into a motor or a sensory neuron. So, there’s a lot more to be learned, but this is one more step in the road to figuring out exactly how our brains are built.
Justin: And if we just went ahead and did it in people, we could learn it faster.
Kirsten: Yes, right. Tell me about your problems.
Justin: An Erie Cancer Researcher has found a way to burn salt water. That’s of course a cancer researcher from Erie, Pennsylvania – novel invention that is being touted by one chemist as the “most remarkable” water science discovery in the century. Which I did’t know there is water science, this is something…
Kirsten: Sure?
Justin: …there is something called water…because I was thinking something…
Kirsten: This study is a study of water.
Justin: Huh, well, I thought it was (hokey). John Kanzius, this is coming from the AP Kanzius happened upon the discovery, accidentally, when he tried to desalinate seawater with a radio-frequency generator he developed to treat cancer.
He discovered that as long as the salt water was exposed to the radio frequencies, it would burn. Discovery has scientists excited about the prospect of using salt water, as a fuel.
Rustom Roy, Penn State University chemist, has held demonstrations at his State College lab to confirm the observations. Radio frequencies act to weaken the bonds between the elements that make up salt water, releasing the hydrogen. Once ignited, the hydrogen will burn as long as it is exposed to these frequencies.
The discovery again, “the most remarkable in water science” – which I thought was a bogus thing, but now it’s been confirmed – biggest discovery in 100 years, most abundant element on our planet, it’s everywhere.” Roy says, “Seeing it burn gives me chills.”
The scientists want to find out whether the energy output from the burning hydrogen, which reached a heat of more that 3,000 degrees Fahrenheit – would be enough to power a car or heavy machinery or generators anything of that nature.
Roy will meet this week with officials from the Department of Energy and the Department of Defense to try to obtain research funding.
He will likely never be heard from again.
Kirsten: Yes. Likely not, like not because it’s not going to go anywhere.
Justin: Burning salt water! Not, but look at this… not a believer…
Kirsten: Color me skeptical.
Justin: …for every desktop fusion, fission, fusion story you brought, you’re going to mock my salt water on fire. How dare you!
Kirsten: All I have to say is that, I mean it’s another method. I mean sure, okay radio frequencies, they’re exciting the molecules at a high enough frequency that you get enough excitation that they break apart, that the bonds break.
And then once they’re broken you have to use other methods to ignite the hydrogen which once electrolysis happens – I mean it’s a process of electrolysis breaking the bonds of water so you have a hydroxide ion and a hydrogen ion. And then you can ignite the hydrogen and that burns and it creates heat and energy and… big whoop. We’ve known about this for a while. I’m not seeing why this is special.
Justin: Basically you’re saying the Penn State professors have basically the equivalent education of a high school science student.
Kirsten: No.
Justin: It’s kind of what you just said Kirs – which I’ll stand behind.
Justin: I think that’s probably true.
Kirsten: I mean if we see this go any further there, that’s great. But it’s like a lot of other things that we’ve seen. I mean it’s people doing the same thing over and over again with water. If it goes any further I’ll be excited about it but this is one story and…
Justin: We’re not going to hear about it.
Kirsten: …yes, we’re not going to hear about it.
Justin: We went to the DOD, the Department of Defense.
Kirsten: Researchers of the University of Tennessee in the Oak Ridge National Laboratory have been looking at how to fold proteins and they found out some pretty interesting information. Protein folding is one of the most important, and also processing intensive research areas around.
Proteins, you go whatever, they’re all around us, we know what they do. They’re a string of amino acids strung together end to end. The amino acids fold up and then they have, they make up the proteins that have active sites that bind to other things, they do things in our body.
They build things, they break things down, they’re super important, right? But the thing is we know that what they look like and they know their final shape but we don’t know how they get to their final shape. Why they take a certain folded configuration as opposed to another.
So, the question that scientists have been trying to determine is what exactly makes it fold a particular way. And so, we’ve got what their – you could be part of FOLDING@home is the way that you can send, leave your computers left online and you have it turned on.
It’s kind of like SETI@home, folding it allows your computer’s processing power to be combined with the processing power of many other computers and allow calculations to take place like, the researchers couldn’t do otherwise.
But this (S-team) in the proceedings of the National Academy of Sciences have been working with a computer called Cray XT4 Jaguar. It’s a supercomputer.
Yes, it’s a supercomputer and what they’ve been looking at are very small strings of amino acids called “peptides”, they’re not full proteins but small ones that do fold up. And their calculations that took place over the millisecond actually over the microsecond timescale.
Justin: Fast, very fast.
Kirsten: So, it’s really fast timescale and this is only the beginning of what they need to be doing eventually in order to understand proteins as whole proteins folding. They need to be able to calculate over milliseconds to seconds in length of time.
Peptides, looking at them, there is a team out of Berkeley that hypothesized that you have small – so there are areas in proteins and peptides that are hydrophobic or hydrophilic. That means that they’re water repelling or water associating. And so, if they’re small hydrophobic areas that water should be able to deal with those but larger hydrophobic areas maybe are too big for water to wrap itself around and so, they end up determining a folding point in the protein.
And so, this is the hypothesis that came from Berkeley, these guys at Oak Ridge National Laboratory actually put their processing power to the test. And they found that they have and I quote, “If you have small hydrophobic molecules or groups that are themselves roughly the size of a water molecule, the water doesn’t seem to be too bothered by these groups.
But when you get hydrophobic entities as long as several water molecules, the water molecules have a problem with that. They can’t cloak themselves around the hydrophobic surface anymore, and there’s a de-wetting or drying effect as they are repelled from the surface.”
And that drying effect determines the structure that the peptide adopts. And what they say is kind of like “dry it off and then fold it up”. So, you have these dry sections that then determine what kind that gets matched together.
Justin: Mm hmm.
Kirsten: We both don’t like water, so we’re going to hide inside of the protein away from the water that surrounds us.
Justin: So, it’s kind a like, I may be extrapolating a little too far, but if you push the paper off of your (straw) to where it’s kind of scrunched up and then you drop water in different sections and that’s where it starts bending at.
Kirsten: Right.
Justin: Except the opposite because it’s a dry spots that….
Kirsten: Mm hmm.
Justin: Oh! Well that made that…
Kirsten: It’s very… that’s possible. So, this is what seems to be happening with the small peptides but now we have to start extrapolating it out too much larger links to get to understand proteins in the full.
Kirsten: …to get to understand proteins in the full. And this might – this is only one aspect of folding and there maybe many other determining factor.
Justin: We don’t have a time once again for my unfolding retrovirus story.
Kirsten: Oh.
Justin: Prions, prions…
Kirsten: Go ahead with it.
Justin: …it’s work from the Bavarian Research Corporation on Prions. Prions being the…
Kirsten: Prions are birds, prions.
Justin: Neither of them are a vehicle made by Toyota.
Kirsten: Yes. Prions are molecules.
Justin: Prions work as a trigger to set disease off in the brain and nervous system including Scrappy in sheep, BSE in cattle, of course the Creutzfeldt Jakob’s Disease AKA the Mad Cow. What they found that… is that genetic – well this getting to be – it’s too long but the thing is retroviruses, these are the viruses that have snuck into our DNA. Our findings – these…
Kirsten: And that make our DNA do their work for them.
Justin: Correct.
Kirsten: Yes.
Justin: But they’re not viruses like you’ve got the cold or something, it’s the DNA of the virus in…
Kirsten: Yes. That’s incorporated into our system.
Justin: …your DNA chain, in your double helix just kind of hanging out there. And what they found is that this Prions…
Kirsten: Gets stimulated or interaction.
Justin: …stimulate the retroviruses to actually produce stuff.
Kirsten: Oh, that might be the cause of some disease.
Justin: That’s what they’re looking into next…
Kirsten: Interesting.
Justin: …to see if there’s a connection between these ancient retroviruses and now the reason why this Prions have this unfolding effect on the proteins in our body.
Kirsten: Fascinating.
Justin: Crazy stuff.
Kirsten: We will be back in just a moment with Rolf Halden. Stay tuned for more, This Week in Science.
(Music)
(Mr. Jones): This isn’t a news report, this is the question. I actually emailed this to another Science show and they touched it. But their answer didn’t satisfy me. If you were to bore a hole straight through the earth from one end all the way to the other, line it with concrete, and insulators whatever, so that you’re not exposed to the heat inside.
Everyone agrees that if you jump down this hole you would yo-yo to a stop at the center of the earth. What I’d like you to ponder upon is how long would you bounce or maybe how long how would you perceive yourself to be bouncing to a stop in the middle.
Two, once you’re in the center, what forces would you feel as you’re suspended in the middle of the earth? Would you feel yourself being pulled every which way or would you feel weightless?
There was once a question about atmospheric pressure, but the other scientist I asked said that the atmospheric pressure in the center should be about the same as on the surface of the earth.
This topic has caused all night arguments with me and my friends. Some feel that you would be absolutely weightless. I personally feel that you wouldn’t be weightless, you would just be pulled, you would feel yourself being pulled in every direction. Not ripped apart just pulled with your own natural body weight in every direction because the earth is all around you now.
Anyway, I hope this isn’t too much of a twist for you. I know it’s a big hypothetical. If you could just touch on this, I’ll be excited. Thanks a lot.
Kirsten: Thank you. If you can answer Mr. (Jone’s) question, send your answer to me kirsten@thisweekinscience.com with the subject heading, TWIS hypothetical. I’ll read your answers on the air next Tuesday, the 25th of September. The best answer will get a 2007 TWIS Science Music Compilations CD.
(Music)
Justin: That’s a perfect song quite a song for this next guest who we’ve got coming up here.
Kirsten: That’s right. We are speaking with Dr. Rolf Halden from Johns Hopkins University. He studies contaminants in microbes in drinking water to determine the consequences of exposure to those agents and without further ado, let’s bring him on the line.
Justin: Good morning. Welcome to This Week in Science.
Kirsten: Hello.
Rolf Halden: Good morning.
Kirsten: Good morning. It’s great to have you on the air with us.
Rolf: Thanks, Yes (unintelligible).
Kirsten: Great. I heard you speak a year ago at a Science Writer’s conference and I was highly intrigued with the data that you presented. And so, I’ve been hoping that I could get you on the air since then and so, I’m quite excited that we could finally put it together.
Rolf: All right.
Kirsten: So, to start I’m really interested in – you study contaminants in the environment, what is it that inspired you to start looking in this direction? What brought you in this field of study?
Rolf: Okay. I work here at the Johns Hopkins Center for Water and Health. We’re looking at the connection between water quality and human health. And by training, I’ve done quite a bit of involvement of Chemistry, meaning finding chemicals out there in the environment. And so, my recent studies have concentrated on mostly man-made chemicals, how they move around in the environment, and whether they pose a risk to human health.
Kirsten: So, there’s something that you’ve called the chemosphere. Can you tell us more about this chemosphere?
Rolf: Well, the chemosphere in scientific terms is essentially the chemical environment that we all are present in. Well, think of it of all the chemicals that you’ve come into contact with, the air you breathe, the water you drink, the food you ingest and the soil you walk on. There’s many, many chemicals in there, actually millions of them.
Some have not been described yet, but there’s at least 26 million organic and inorganic chemicals, meaning ones for the looking like a carbon and others that are non-carbon chemicals like metals, and there’s – and millions of them really. And in terms of understanding human health we want to understand the interaction of those chemicals that potentially are toxic.
Kirsten: Right. How many are – so, there are millions and millions about 26 million you say in the environment. How many of those are just natural chemicals versus those that we produce as humans and put into the environment?
Rolf: The complexity really always existed in terms of biological organisms producing a lot of chemicals. But mankind also has contributed a fair amount of new chemicals to the chemosphere.
So, we are looking at about 240,000 chemicals that are inventoried and regulated by governments worldwide that means essentially that we produce these. And about 82,000 chemicals are routinely used in commerce here in the United States. And out of those we have about 4,800 so, about 5,000 that are produced at quantities exceeding one million pounds a year.
Justin: Wow, that’s quite a startling amount. And especially because all these other chemicals that are in the environment, we basically grew up with them, right? We’ve evolved alongside them so, if there was any weird interactions early on, it has probably been overcome. These new chemicals that we produce with our industry and what have you – they’re almost as though they came from another planet. They’re sort of alien to the earth, correct?
Rolf: Well, some do and some don’t. I like the thinking here so, in essence we evolved together with this complex chemistry and living organisms have evolved mechanisms of detoxifying chemicals making them less harmful. But some of the chemicals we’ve put out into the environment today, they look like nothing that was there before.
And these chemicals indeed have produced the biggest problems in human health concerns for mankind and for the earth’s population too. What comes to mind is maybe DDT, maybe the listeners can make the connection there.
Kirsten: Yes. That’s gone through.
Justin: Yes, we’ve still got it in our produce out here. It shows up, even on the organic farms sometimes.
Rolf: Yes. That’s a good point so, why is it still there, obviously it has been banned in the 1970’s because it almost wiped the Bald Eagle population of the US. But the chemical is still detectable in the environment today because no mechanisms exist to break it down.
And the reason for that is because its structure is not one of biological origin. So, we have made it and no enzymes, no breakdown mechanisms have evolved alongside with the chemical. And that makes it difficult for these chemicals to be removed.
And DDT is just one of these types of chemicals that we put out into the environment that potentially can persist over long periods of time. Essentially from a toxicological point of view, we are always interested in chemicals that what we call halogenated organic chemicals.
We take a chemical that look like it’s made by biological organism and we take the hydrogen’s off and add halogen atoms to it. These are chlorines, fluorine’s and bromines, and with that type of structure, the chemicals often turn out to be fairly persistent in the environment.
Kirsten: And that persistence means that they’re going to accumulate up through the food chain most likely. If they’re persisting in the ground they might be taken up by plants, eaten by plants, eaten by animals, that then other animals eat, and could eventually, if they have some kind of deleterious effect, have severe consequences.
Rolf: That’s right, that can happen. So, essentially the longer the chemicals sticks around in the environment, the more it can move about and find places where it’s unwanted and causes adverse effect. It could be in the environment in aquatic organism or it could come back to us and hurt us in some way.
And so, we are concerned about this what we called persistent chemicals that are moving around in the environment, make it all the way to the polar caps and you can detect them in Polar bears for example as they are the top predator.
And they accumulate a lot of the chemistry that has been moving up through the food chain. So, we see a lot of toxicants that accumulate to high levels in predatory animals, and also in humans.
Kirsten: Yes. That’s just amazing to think the things that we can do down here can end up in the water, end up going circulating to the North, to the Arctic and reflecting…
Justin: It’s not really that far away though.
Kirsten: It’s not that far away but still the cycle is an interesting cycle. Now you’ve studied a lot – your recent research has been focused a lot on triclosan and trichlocarbon . Can you tell me a little bit about why those molecules are interesting?
Rolf: Yes, I became interested in triclosan and trichlocarbon because there’s a connection to public health. These two chemicals are added to consumer products that are labeled anti-microbial or anti-bacterial. You might have seen that in the store where you pick up a bar soap.
Justin: Oh, it’s everywhere. I have a hard time finding non…soaps without it now.
Rolf: Exactly. So, mostly these chemicals are added to soaps, bar soaps and liquid soaps and now particularly triclosan also has other uses. It’s being added to textiles, to kitchen utensils, to toys and even like shoe soles and other items, deodorant contains it.
So, these are chemicals that also are man-made, they carry three chlorines each on two eremitic rings, so in a way they look a bit similar to chemicals that have caused problems in the past before. And so, we’re interested in finding out how these chemicals behave, particularly because we apparently produce much more than we did just maybe a decade ago.
Kirsten: Right. How much has the production increased over say the last decade or 20 years?
Rolf: Well, both triclosan and trichlocarbon are labeled high production volume chemicals by the EPA. So, they are on the order of at least half a million to greater than a million pounds a year of chemicals used in United States and worldwide the number is higher.
And whenever you produce a chemical at this type of scale it’s a good idea to find out what exactly happens to it in the environment and that’s some of the work that we did in the past 2 years.
Kirsten: Have you been studying where they go in the environment?
Rolf: Oh, essentially we began by looking at waste water. If you think about it if you buy a piece of soap that is anti-bacterial and you used it then you essentially come in contact with it shortly for a few seconds when you wash your hands and then it’s washed down and the water ends up in the drain and then it’s carried to a wastewater treatment plant.
And so, we have asked a question of whether these chemicals are detectable for example in surface waters where the wastewater treatment plant discharge the effluent into. And our data and those of the United States Geological Surveys show that these chemicals are quite abundant in the environment.
The USGS showed that at about 58% of surface waters contain detectable concentrations of triclosan. And fairly it’s a low levels because it is highly dilute and the trichlocarbon also is detectable at these low levels which are nanogram per liter concentrations.
Justin: Is there some sort of an interaction possible between these chemicals and, I heard though it was a story a while back and I don’t remember the details of it, but a potential interaction between the chlorine that we used to treat our water, and these chemicals like if we’re washing our hands.
Rolf: Yes, actually I think the research really has exploded so to speak for triclosan particularly. Since so many products contain triclosan, it became the research focus of a lot of scientists.
And initially this chemical was only studied by the industry that wanted to use it, wanted to demonstrate that it’s safe. And now a lot of other people are looking into it and they look at… in new locations for the chemicals and find it. And they also sometimes find effects that weren’t known before and that are potentially of concern.
What you are referring to right now is the process of drinking water chlorination to provide safe drinking water, we use chlorine, and chlorine in the water to wipe out pathogens.
Kirsten: Yes.
Rolf: And if there’s residual amounts of triclosan present in the raw drinking water, then potentially you can have the formation of chloroform which is a known human carcinogen.
Justin: Chloroform, that’s what it was.
Rolf: Mm hmm.
Justin: Chloroform in my drinking water, which is great, because the next town over, like this town we’re on well water it’s… the water is undrinkable. So, it’s horrible, it’s horrible, but it doesn’t smell of chlorine. The town next door they use all river water, and it smells, sometimes the water in that town smells like a swimming pool. So, that’s it they’ve used – I mean they over chlorinate sometimes.
Rolf: Yes. But chlorine is a good thing.
Justin: Oh yes, yes.
Rolf: If you look at the health statistics since we have the chlorination process, which was implemented like in the 1920’s for the most part, we saw a dramatic decline in infectious diseases. You have to realize that from a public health concern or standpoint, we are most concerned about infectious diseases and then about chemicals. So, we’re looking in an acute health risk potentially life threatening with infectious agents.
And then we’re looking at the long term maybe cancerous risk or some other outcome if we look at chemical exposures. So, it really is important, you know, if you smell chlorine it might not be pleasant but, you know, you can be assured that you don’t ingest viable infectious agents.
Justin: But if 58% of the water that they are using to put into that chlorinated system to give you the clean water might have, be having, might be creating chloroform when you take your shower, it just gives you another reason not to use the anti-bacterial.
Kirsten: It’s not when you take your shower, it’s the chloroform would be produced earlier in the process.
Rolf: Yes. So, actually we have made great strides in protecting people, but we also made kind of a mistake in that we sometimes use too much chlorine in the disinfection process.
So, decades after we found out that we did a great job in eliminating the pathogen. We then noticed that there are some products being formed as the chlorine hits the raw water that are not only unpleasant, but actually a potential health risk.
And so, we’re looking at trihalomethanes. These are small molecules that again carry halogen (constituents) and so, chlorine or bromine atoms. And we found out that these are potentially harmful. And so, they have been regulated for several decades now and we’re keeping an eye out on those.
Justin: So, the danger is for the guy working at the water treatment plant, not for me.
Kirsten: Yes, right.
Justin: Okay, he gets paid good money.
Kirsten: Now the… one of the – I mean the key use for a trichlocarbon and triclosan is an anti-microbial agent, now what is the research saying now about these compounds staying in the water through the waste treatment plant into the environment and how are they affecting resistance of bacteria in our environment?
Rolf: So, what we found out so far, and when I say “we” use it in scientific communities, so both triclosan and trichlocarbon are fairly persistent in the environment. We can walk up to essentially every other stream in the United States and scoop up some water and we will find both chemicals in there as the detection frequency is about 60%.
And we also know that the wastewater treatment plants are not as effective in destroying the chemical as we would like them to be. It turns out that when wastewater containing triclosan and trichlocarbon enters the wastewater treatment plant, most of these chemicals are being removed from the water. So, fairly clean water exits the plant and is being discharged typically into surface water. But that doesn’t mean that the chemical is being destroyed.
We just published a paper earlier this year, where we demonstrated that for triclosan for example about half of the mass that goes into the plant is not destroyed and is ending up in unusable biosolids, unusable sludge.
Justin: Is there a potential – and this is I guess more biological than chemical, creating an enzyme that is designed for breaking down these new chemicals? Micro Engineering something to…
Rolf: It is possible to do that but it’s very expensive and you start to wonder whether you actually need to do this. I think the first question should be, do we actually need the chemical? And if we do need it, in what quantities and for what specific applications do we need chemicals?
Kirsten: Right.
Rolf: You would ask this type of question a little earlier I think we could have avoided, looking from a historical prospective a lot of issues there that we are still struggling with today. So, overuse of pesticides has given us environmental problems and human health concerns.
And maybe we see a similar situation with triclosan. If you look at the literature, you will find out to your surprise that triclosan really is not proven in providing a health benefit to the average consumer relying on anti-bacterial soap.
Justin: Really.
Kirsten: Yes. No it doesn’t.
Rolf: A lot of people don’t realize that this is actually…was just peer reviewed by a group in Michigan and they reviewed all the available studies and demonstrated that there’s no considerable benefit in using these chemicals.
And so, whenever you have a potential risk and it’s not balanced by a benefit then I think, it would be very easy to just eliminate the use of the chemical or hand it down to those applications where it actually makes sense.
And these anti-microbial agents, they do play an important role in clinical setting. So, if you’re in an operating room, you want a sterile environment so that you don’t catch an infection.
And for these types of applications in clinical setting, these agents are important and potentially life savers, but they have essentially no role for the average consumer washing their hands.
Kirsten: Yes. What are some of the negative effects of triclosan and trichlocarbon? What is known about what they do, when they do get out into the environment?
Rolf: Yes so, now after understanding that the chemical breaks through waste water treatment plants to some extent and contaminates surface water and also accumulate in these municipal biosolids that are then applied in agriculture. We’re now, under the gun to find out what that means, what the implications are.
This is not easy because there’s many organisms living for example in soil where you apply these municipal biosolids. However, there are studies that have shown that if you have take a pathogenic organism and expose it to triclosan, that this organism can become cross resistant to 7 out of 12 clinically important antibiotics that were tested.
Kirsten: Great.
Rolf: But essentially…
Justin: Super bad.
Rolf: …the bacteria they get more robust and they can deal with drugs that previously were effective.
Kirsten: Yes.
Rolf: It was of great concern to the medical public health community because the antibiotics are our last resort in treating infectious diseases and we cannot afford to risk reducing the efficacy.
Justin: It’s one thing about these microorganisms is that they do what we can’t, which is reproduce constantly and share DNA so that they’re in a sense, learning how to evolve with and grow up with these chemicals that is going to take us several, several, several generations of evolution to ever get into some sort of balance with.
Rolf: Mm hmm. Now the scientific challenge right now is, so in the laboratory it was demonstrated that triclosan can cause multiple drug resistance, in pathogens. But this process has not been observed in the environment yet. It doesn’t mean that it doesn’t occur there, it might or it might not.
Kirsten: Right.
Rolf: But we have not looked and we – unless we look we will not find it. So there’s important questions that we now are asking, also, is the chemical bio-accumulating like other polychlorinated heremetics do. And this work is just beginning. So, really, we have not even understood now where the chemical, what places the chemical migrate. And then the next step is once you find out where it is, you start to study what exactly happens there.
Kirsten: Yes. Wasn’t there a study with triclosan in the environment actually found in what is considered a bioactive quantity in the microgram range. And, what is it… frogs I think it was – and it actually having some kind of an effect on their reproduction.
Rolf: Yes. So, the safety of these products, that is a complicated issue.
Kirsten: Yes.
Rolf: You think about it, when you go to a store and you pick up a bar soap containing for example a trichlocarbon. It contains about 2% by weight of trichlocarbon. It’s a huge amount. You can essentially take a slice of the soap and that slice represents part of the active ingredient contained in that soap. This is a huge dose or a large amount of chemical mass.
But you’re not getting exposed to it for a long time and you would get exposed through the skin rather than ingesting it. When the chemical ends up in the waste water it immediately gets diluted and that continues through the waste water treatment plant and the water exiting the plant has only nanograms per liter. So, there’s millions of times dilution going on before the chemical hits the water.
Kirsten: Yes.
Rolf: So, in essence if you these traces of these chemicals in drinking water from a toxicological point of view this is not an issue for us, but it might be for the organisms that spent their lives swimming in that water. And so, naturally the first study that we conduct when we find these man-made chemicals in water is towards looking at the effects on aquatic life like algae or frogs and fish.
And so, indeed the recent reports indicate that there are some adverse outcomes. For example algae can bio-accumulate the chemical by up to a factor of 3,000 by one recent report. And then there was evidence for disruption of thyroid hormone… abounds in frogs, initially.
Kirsten: Right.
Rolf: And fairly low levels of these were 30 nanograms per liter were tested in vitro, meaning in the test tube. And this very low concentration that are kind of typical for what we find in the environment right now were demonstrated the laboratory to have an noticeable effect.
And then these studies or these outcomes of impacting the thyroid hormonal imbalance were replicated not only in these aquatic organisms but also in rats lately. So, there’s a study now indicating that high doses of triclosan… it functions as endocrinic ruptures in rats.
Justin: And all of this for something that has no discernable health benefits.
Kirsten: And are we finding that similar levels in human blood it… have those studies been done?
Rolf: Well, whenever we mass produce a chemical that is fairly persistent we will find it and particularly, if we use it in personal care products, you can count on the fact that some of it will enter the human body. So, there’s many reports on the occurrence of triclosan and essentially you can detect it in urine, routinely in the majority of the population.
And it is also detected in blood, in human blood and it can be most detected in 97% of breast milk samples. So, the chemical is detectable at low levels, sometimes at little elevated level in number of biofluid. What that means in terms of human health, that is a very complicated question.
Kirsten: Right.
Rolf: I think there’s no doubt that these chemicals move about and that even people who don’t use these types of products certainly get exposed at this time because the chemicals are so abundant in the environment, even house dust contains a fair amount of triclosan through the presence of skin shavings.
And so the chemicals are present in the environment and current risk assessments data suggest that the levels that are present and that can be found in biofluid are not of a concern to human health. But that doesn’t imply that it’s not a concern to the aquatic bio-order for fish and frogs and so forth.
Kirsten: Right. So, even though it might not be affecting us necessarily at this point in time, it could have other effects that could be far reaching throughout our planet.
Rolf: Exactly. So, I think there’s an opportunity to kind of rethink the type of chemistry that we mass produce. I believe that whenever we manufacture large amounts of chemicals, it would be a good idea to think about whether an appropriate mechanism for their breakdown exists.
And if doesn’t, then we really should second guess whether we want to use and manufacture this chemical. Because history shows that a lot of the chemicals that turned out to be persistent in the environment, and first was thought to be safe, and later on were deemed unacceptable because of an outcome that was very difficult to foresee.
Kirsten: Right. We are out of time. Thank you so much for all this information. It’s been great talking with you today.
Rolf: You’re welcome.
Kirsten: Thank you. And I wish you luck in the rest of your research and…
Rolf: Thanks.
Kirsten: …keep protecting our environment.
Rolf: We’ll do our best.
Kirsten: Yes. Thank you. Bye. And that’s it for us today with This Week in Science. Stay tuned next week for more Science.
Justin: If you’ve learned anything from today’s show remember…
Kirsten: It’s all in your head.
Edited by: Paul V.
The podcast can be heard here: http://www.twis.org/audio/2007/09/18/148/