Ep 38 Lead Poisoning: Heavy Metal Episode

00:00:00
Speaker 1: John was a well nourished, playful, and co operative child with no history of developmental problems. According to the admitting nurse, John was admitted to the hospital because he had developed an ear infection, but that was easily treated. In the ensuing months, John returned periodically to the clinic for treatment of his chronic ear aches, but by the time he was two years old, he had developed symptoms that were not at all routine. In May nineteen forty one, his parents rushed him to the hospital. A few hours earlier, he had bent over to the left and couldn't straighten up, they told the admitting nurse, and since that time he had been acting crazy like John had been eating plaster, they said, and the previous day he had eaten some paint. At the hospital, he fell to the left side when he tried to walk, and he reeled around to the left. He didn't respond to his name or questions. The hospital raised the possibility that John suffered from lead poisoning, encephalitis, and secondary anemia. The blood work showed three hundred and ninety micrograms of lead per desolator of blood, almost eighty times the level considered by the CDC to be dangerous for children seventy years later and at the time clearly a cause of acute poisoning. When told that paint from the window sills was dangerous, his mother said she had not realized its danger and had caught him on frequent occasions with a mouthful of paint chips. She promised that in the future she would make every effort to keep the child away from the paint. In mid June nineteen forty one, after more than a month in the hospital, john symptoms subsided and he was sent back home, But two months later the mother was back at the social service department. In the words of the social worker, the family had contacted the real estate agency several times about repair work, but with no success. There continued to be problems of loose plaster throughout the home in spite of their efforts at repair. The social worker contacted the health department, which promised to investigate the home conditions, but we know neither the results nor what befell John in subsequent years. Wow, Yeah, that's so sad. Yeah, it really is, unfortunately not uncommon.

00:02:51
Speaker 2: Oh no, that's like one case, that's like one story of millions.

00:02:56
Speaker 3: Yep.

00:02:57
Speaker 1: Yeah, So what was that from that was from the book Lead Wars. Hi.

00:03:06
Speaker 3: I'm Aaron Welsh and I'm Erin Almond Updyke and this is this podcast will Kill You. And today we're talking about lead poisoning. Lead poisoning. Yeah, it's a huge topic. Do we say that every single time? Yeah, we absolutely do. Is it always true? It always is?

00:03:26
Speaker 2: Yeah, I'm excited for this one though.

00:03:28
Speaker 1: We also say that every time. And it's also true every time.

00:03:31
Speaker 3: I know this is genuine people, really is Okay?

00:03:37
Speaker 2: Well, it's also quarantine garantiny time.

00:03:41
Speaker 3: That's right. What are we drinking this week? Today? We're drinking the Fall of Rome.

00:03:47
Speaker 2: We are then, it's named that for reasons that I will tell you later on in the episode.

00:03:51
Speaker 1: Yes, it will become quite clear if you can't figure it out already.

00:03:55
Speaker 3: And what is in the Fall of Rome? It's basically a sangria, it is.

00:04:00
Speaker 2: So it's red wine, brandy, cut up oranges, lemons, green apples, and then a cinnamon stick tossed in there, and maybe serve it over ice with a splash of club soda.

00:04:12
Speaker 1: Try to avoid leadlined mugs.

00:04:16
Speaker 2: Yes, please avoid leadline mugs.

00:04:18
Speaker 1: We will post the full recipe for our Quarantine UNI, as well as our non alcoholic plusy Berita version on this podcast, will Kill You dot com, as well as all of our social media channels.

00:04:29
Speaker 3: Yeah, we have.

00:04:30
Speaker 1: Merch including shirts, mugs, not leadlined, nope, sons, etc. All these are available from our website. Just click on merch.

00:04:44
Speaker 3: That's all.

00:04:44
Speaker 1: Let's just talk about lead poisoning.

00:04:46
Speaker 3: Show's do it. Let's do it all right, but first let's take a little break.

00:05:14
Speaker 1: All right.

00:05:14
Speaker 3: So lead.

00:05:16
Speaker 1: Everyone knows what lead is, right, I mean, it's a metal, It's a metal. Okay, episode over, just kidding. Lead is a metal, it's a heavy metal. It's an element on the periodic table PB. That's its name. I assume you're gonna say why, right, Erin.

00:05:35
Speaker 3: I'm very excited about it.

00:05:37
Speaker 1: Actually excellent, good because I'm not going to say why. And I've done a lot of biokem on this podcast, but never have I had to do pure chemistry before.

00:05:48
Speaker 3: Ooh fun, I'm.

00:05:49
Speaker 1: Not gonna do it, Erin, Aaron, I can't. I don't know enough chemistry to be able to explain it. Well, okay, okay, we're just going to talk today about what happens one's lead gets into your bodies.

00:06:01
Speaker 4: Okay, it seems like chemistry to me, but sure, sure that doesn't feel like chemistry. In our bodies, lead, the element exists as what's called a cat ion. That means that it's a positively charged molecule. Okay, So as it floats around through our bloodstream, it's floating around as a single molecule that is positively charged. Because it has a positive charge, it's attracted to other things in our blood that are negatively charged. If you think of something like a magnet where you have a positive and a negative pole, Yeah, it's just like that. Inside of our bodies, positive things are attracted to negative things and vice versa. Okay, So in our bodies, it turns out that one of the things that is negatively charged are proteins. Okay, oh protein, Yeah, proteins, yeap. Pretty much proteins are negatively charged. They have an end group that is negatively charged, and so lead in our bodies tends to bind to proteins.

00:07:03
Speaker 3: That's really interesting.

00:07:04
Speaker 2: Also, I feel like I should have known that all proteins were negatively charged, and now I'm embarrassed.

00:07:09
Speaker 1: But hey, you know what, you don't have to be embarrassed there, and there's always things to learn, all these things to forget too. So a lot of the toxicity of lead poisoning is because lead ends up binding to proteins and screwing up the way that they function. Makes sense, That's kind of the basic pathophysiology of it, Okay. The other thing is that because essentially all lead is, I know, it's it's kind of hard to think of lead as just this positively charged molecule because when you think of a metal, it's like this, like a piece of metal, right, right, But in our bodies it's just a tiny little ion. And because it's so tiny and because it's charged, it can pass freely across a lot of membranes very easily.

00:07:50
Speaker 4: Oh okay, Okay, which is also bad news, very bad news, because it's not supposed to be in our bodies.

00:07:57
Speaker 3: Okay.

00:07:58
Speaker 1: So what I'm gonna do first, now that you you know the very basics of why how lead can end up causing problems in our body. It binds to proteins and it can cross membranes, We're gonna first talk very quickly about what it might look like if somebody, say, came to the emergency room or their doctor. What are the kinds of symptoms that might make someone think, hey, this could be lead poisoning, and then we'll talk about exactly how each of those symptoms might happen. Okay, all right, So the common symptoms that might make someone think we're looking at lead poisoning are things that are actually pretty general. Abdominal pain, especially very severe abdominal pain, joint pains, severe headache. You might have increased intracranial pressure, which means increased pressure in your cranium in your skull. And then neurotoxic effects, which we'll talk in more detail about anemia and kidney dysfunction.

00:08:57
Speaker 2: Okay, and so this is all like these things could all happen at once or over the period of weeks or like, what is the time scale?

00:09:06
Speaker 1: Great question. The timescale kind of depends on the timescale of exposure.

00:09:10
Speaker 3: So a lot of.

00:09:11
Speaker 1: These symptoms you might not see until blood lood blood lead levels. That's going to be so hard to say for this whole episode, by the way.

00:09:19
Speaker 3: Well, is it as hard as gerardia?

00:09:21
Speaker 1: Yes, maybe harder, But until blood lead levels are above about sixty that's when you might see some of these acute symptoms like abdominal pain, and joint pains. But lead is something that can build up in your body slowly over time, or you could be exposed to a large amount in a short period of time. So it kind of just depends on what your exposure is and where you were exposed. Okay, okay, So we talked about those general symptoms. One of the big things that we see in lead poisoning, and even though it's probably not the most detrimental or acutely important.

00:09:59
Speaker 3: Is anemia. Yeah.

00:10:00
Speaker 1: Anemia means low blood count, So low red blood cells, okay, not enough red blood cells. Your red blood cells are what carry oxygen. So that's pretty important, right.

00:10:12
Speaker 2: We've talked about it in a hookworm, I think.

00:10:14
Speaker 1: Yeah, we totally did for sure, yea, And in hookworm it's totally different because you're losing blood. What happens in lead poisoning is that lead actually blocks the action of an enzyme. Remember that enzymes are proteins, and lead is binding to proteins. It binds to and blocks the action of an enzyme that is essential for the synthesis of hemoglobin, which is hemoglobin is what's in your red blood cells that actually carries the oxygen. So if you can't make hemoglobin, then you can't make red blood cells, then you can't carry oxygen, and your anemic.

00:10:51
Speaker 3: Okay, that's interesting.

00:10:54
Speaker 1: Yeah, it also ends up leading to a number of different problems down the line where it can cause kidney dysfunction, both because it's messing up hemoglobin synthesis and because it actually can deposit in the tubules of your kidneys and cause direct damage to your kidneys.

00:11:17
Speaker 3: Yikes.

00:11:18
Speaker 1: Now, your kidneys, as it turns out, are really important in regulating your blood pressure.

00:11:24
Speaker 3: Right, so if you start.

00:11:25
Speaker 1: Messing with your kidneys, you can end up causing your kidneys to raise your blood pressure in your body. Why does it raise the blood pressure because, great question. So your kidneys. The way that they interact with your blood pressure is when your kidney sense low blood flow, they release a hormone that tells your brain, Hey, we've got low blood flow. You need to increase the blood pressure. Oh and so yeah, so the damage that lead can cause to your kidneys reduces the flow of blood through your kidneys, and that releases hormones that says, hey, the blood pressure is low, we need to constrict our vessels and increase this pressure. But when in reality, what ends up happening is then you have high blood pressure hypertension.

00:12:10
Speaker 2: Because it's not about the blood volume, it's about these like false signals exactly exactly. Oh cool, yeah, okay, okay.

00:12:18
Speaker 1: So now we've talked about hemoglobin, we've talked about kidney dysfunction, we've talked about hypertension. That was so many things all at once, boom. Another thing about lead is that so it's this charged molecule, right, It turns out it's functionally kind of similar to calcium. Calcium is also a charged molecule, a positively charged molecule. So lead can compete with calcium in our bodies. Where do you find calcium in our bodies? Erin bones, bones, So lead can end up depositing in bones. It can deposit in joints, and it can disrupt the normal synthesis of bones.

00:12:56
Speaker 3: So this can cause.

00:12:57
Speaker 1: Joint pain, bone pain, and then all things like osteoporosis or osteopenia.

00:13:02
Speaker 3: And that's how you can see lead poisoning.

00:13:05
Speaker 1: Yes, an X rays, lead lines in X rays. Now, as we know, it's a small charge molecule, it can cross membranes, it can cross the placenta. So in pregnant people with high lead exposure, it can cause still birth or different types of malformations in the fetus. It also can cross the blood brain barrier classic classic, So that means it interferes with our central nervous system. It does this in a whole bunch of different ways. So by binding to certain enzymes or certain proteins, it can inhibit the release of important neurotransmitters, things that your brain releases to communicate with your body. It can increase the release of others. So it basically just completely messes up the normal functioning of your central nervous system. So some people with lead poisoning a very classic sign are certain types of peripheral neuropathies. So nerve problems in your peripheral nervous system as well as your central nervous system. So you might have things like what's called wrist drop where you can't flex your wrist anymore, huh, or foot drop where you can't flex your foot anymore. Yeah, And so that means you can imagine it might lead to things like clumsiness because your feet aren't working properly, weakness. In severe cases, it can lead to paralysis, and once it gets into your central nervous system. Your brain can actually end up absorbing that lead directly, which can lead to direct neurotoxicity on your brain cells.

00:14:42
Speaker 3: That sounds pretty stink and bad.

00:14:45
Speaker 1: It's pretty stink and bad, yes, Okay, So in children this is especially bad, yeah, because it can end up interfering with the development of the nervous system. Right, So let's talk about children in more specific because both adults and children are susceptible to lead poisoning, but children are especially susceptible. There's a number of reasons why. First of all, in adults, only about one tenth of the amount of lead that you ingest, like through your mouth or your mucous membranes, is actually absorbed in your gi tract only about ten percent.

00:15:26
Speaker 3: Okay, okay.

00:15:27
Speaker 1: If you inhale lead, about forty percent of that lead is absorbed through your lungs. So inhalation of lead is a lot worse than absorption. But in children, their guts, because they're not fully developed, probably actually absorb a much higher proportion of the lead that they ingest. Oh, so they're absorbing lead at a higher rate. So right after the bat they're at higher risk. But because kids are Also kids, they're more likely to like eat dirt that might be contaminated, to lick a lead paint.

00:15:59
Speaker 2: Water, just put their hands in their mouths.

00:16:02
Speaker 1: Exactly right, and so they're more likely to be exposed to lead in the first place, and then they're absorbing more of what they're exposed to.

00:16:10
Speaker 3: Oh wow.

00:16:11
Speaker 2: So I my assumption was that it was just the behavioral risk was higher for children. I didn't realize it was also their bodies like a physical higher risk category.

00:16:21
Speaker 3: Aaron, it gets even worse. H oh no.

00:16:23
Speaker 1: Yes, because children's blood brain barrier isn't fully formed, lead is even more likely to make it into the central nervous system.

00:16:31
Speaker 3: Oh my gosh.

00:16:32
Speaker 1: And because their central nervous system is still developing on a cellular level, they're more susceptible to the effects of lead on their nervous system cells.

00:16:42
Speaker 2: So it's like a lot more permanent damage can be exactly yep.

00:16:46
Speaker 3: Yeah.

00:16:46
Speaker 1: It also distributes in their body tissues differently, so it's more likely to go into soft tissues than it is to bones in children versus adults. And that probably also has to do with just the differences in like water and fat content in babies versus adults and things like that.

00:17:03
Speaker 3: Okay, yeah, I.

00:17:04
Speaker 2: Have I like a question what is considered a child, Like at what point do they become no longer at like a high risk category. I assume it's a spectrum, right, with certainly just being of higher risk.

00:17:14
Speaker 3: But that's a really good question.

00:17:16
Speaker 1: So in looking into this, a lot of the data looks at children who are school age because that's when you can start to see some like of the behavioral and like neurocognitive issues that can develop. But lead exposures in children tend to be highest when they're about two years old or less. Okay, so that's when exposure risk is the greatest is when they're very little, because that is when they're toddlers and putting things in their mouths and stuff like that. But that's a good question in terms of, like, your brain isn't fully developed until after you're a teenager, so presumably the effects in that your susceptible effect wise would continue through young like adolescents. Okay, but the exposure is going to be a lot less in that age group.

00:18:01
Speaker 3: Okay, gotcha.

00:18:03
Speaker 1: That's a really good question though. Okay, So while the early symptoms of lead poisoning or the acute symptoms of lead poisoning in children might be similar to adults, where they'll have things like abdominal pain, joint pains, clumsiness, staggering, things that we heard in the first hand account. Once the brain is involved, it can get a lot more serious and a lot more long lasting in children, because if a child is exposed to high levels of lead, once the brain is involved, it can progress to loss of consciousness and eventually death. If they survive, though, they often have lasting cognitive impairments. And what we have found that has taken unfortunately too long, is that even at very low levels, chronic exposure can also cause these kinds of cognitive impairments.

00:18:54
Speaker 3: Right, there is no safe level.

00:18:56
Speaker 1: There is no safe level exactly, Aaron. There's also some interesting research into what happens. So in your blood stream, lead only lasts for about thirty five days. That's the half life of lead in your blood. It's about thirty days, so your kidneys actually are helping to excrete lead. But once it deposits in your bones, the half life is like ten to twenty years.

00:19:21
Speaker 3: Oh my gosh.

00:19:22
Speaker 1: Yeah, so lead can if you're exposed to very high levels of lead while you're young, and it ends up depositing in your bones. It can be many years later where that lead sort of slowly leaches out of your bones.

00:19:35
Speaker 2: And then once it leaches out of your bones, then it's in still in your body.

00:19:39
Speaker 1: Still it goes into your bloodstream, and from there it can potentially still cross the blood brain barrier and end up affecting your brain.

00:19:46
Speaker 3: Wow.

00:19:48
Speaker 2: Could you as a child have been exposed chronically to lead and then you only see it twenty years from then?

00:19:56
Speaker 3: Great question. Arin.

00:19:57
Speaker 1: There's now some research being done where it seems like elevated lead in elderly people that were exposed when they were young, like people who are elderly now who were exposed to high levels of lead when they were young, because it used to be that pretty much everyone was being exposed to high levels of lead can actually lead to cognitive decline and dementia in elderly.

00:20:20
Speaker 2: People because it's finally leaching out of their bones exactly into their blood brain barrier. Oh my gosh, or crossing a blood brain barrier.

00:20:27
Speaker 3: Holy cow. Yeah.

00:20:29
Speaker 1: Yeah, So yeah, that's lead poisoning biology wise.

00:20:36
Speaker 3: Wow. Mm hmm.

00:20:38
Speaker 1: We do have treatment, but really the treatments that we have. It's called keelation therapy, where you basically, either orally or through IV give drugs that help to bind up the lead so that it doesn't cross your membranes and get into your organs and you can.

00:20:55
Speaker 3: Just excrete that lead.

00:20:57
Speaker 1: It really only tends to work if your blood levels.

00:21:00
Speaker 3: Are quite high, like forty or sixty.

00:21:04
Speaker 2: Okay, so if you do kelation and you your blood levels are fifteen, that.

00:21:11
Speaker 1: Doesn't seem to do much from what I have read, yea. And what else happens is if you have very very high levels of lead in your blood that doesn't reflect your total body concentration of lead. So even for example, like the child John in the first hand account who had three hundred and ninety's that outrageously high. Once you give keelation therapy, that will reduce your blood lead levels, but then over time it will start leeching out of your organs and your bones where it has already deposited, and your blood levels will rise again to sort of equilibrate, and then you might have to kelate multiple times, which is probably why he was in the hospital.

00:21:55
Speaker 3: For so long.

00:21:56
Speaker 1: Yeah wow, yeah, So the most important thing to do with lead poisoning is to eliminate the source of exposure to begin with, figure out where someone was exposed, and try to stop that exposure and prevent it from happening in the first place.

00:22:12
Speaker 3: Yeah. Well yeah, I'll get into it. Yeah. Yeah.

00:22:18
Speaker 1: So yeah, that's the biology of how lead really does.

00:22:21
Speaker 3: The number on your body. It really does. Yeah.

00:22:25
Speaker 1: So Aaron, how did it get here?

00:22:29
Speaker 3: What the heck? Great question.

00:22:32
Speaker 5: Let's take a short break. Okay, Lead.

00:22:57
Speaker 2: This was a really interesting episode to research because it was so different than what we usually do.

00:23:02
Speaker 3: Oh my gosh. Yeah.

00:23:04
Speaker 2: So it's like, instead of reading about the evolutionary the evolutionary origins of this or that bacteria or virus or something, I got to read about how humans used a metal in different ways throughout history.

00:23:15
Speaker 3: Oh that's cool, yeah.

00:23:17
Speaker 2: And what that meant for their health. Okay, let's get started. So it turns out that lead is one of the longest used metals, Like it's.

00:23:25
Speaker 3: Been around for ages. There's no lead age the.

00:23:28
Speaker 2: Way there is like an iron age or a bronze age, but lead was used during all of these metal ages. And the reason that there wasn't a specific lead age is because it's not a very sexy metal like it's it didn't really cause like a revolution, I guess, or like a huge change that.

00:23:46
Speaker 3: I mean, it's.

00:23:47
Speaker 1: Title lead not a very sexy metal.

00:23:49
Speaker 3: Not very sexy metal.

00:23:51
Speaker 2: Lead is soft and dull, and so people didn't really want to use it in jewelry or decoration or making weapons. Instead, lead was used to carry out some of the grunt work like plumbing, architecture, et cetera, especially in Greek and Roman times, and it was also used for pigments going back to the Paleolithic times. Wow, it's been around since people since before people.

00:24:14
Speaker 3: Could write about lead.

00:24:15
Speaker 1: Yeah, I mean it's it's just a part of our earth, so that makes sense. But wow, that's it's so interesting that humans were using it for so.

00:24:24
Speaker 3: Long, so long.

00:24:26
Speaker 2: Okay, how about some etymology real quick. Yes, I think this might be one of the most exciting etymology things that we've done on this podcast.

00:24:34
Speaker 3: For me, I don't know.

00:24:36
Speaker 2: Okay, this is not really etymology. But so, first of all, the use of lead was so widespread in ancient times that there's even an Egyptian hieroglyph for lead.

00:24:45
Speaker 3: What isn't that cool? Yeah?

00:24:48
Speaker 2: Okay, but etymology, So, as you mentioned, The chemical symbol for lead is PB capital P, lowercase B, and that actually comes from the Latin plumbum plumbum, which actually has older roots even in some pre Hellenistic language, so like pre Greek, and plumbum was used to refer to basically any metal that was silvery, had a low melting temperature, and was easily oxidized. And these are the characteristics of lead, along with tin, zinc, and some other metals and alloys. To distinguish from the rest of those metals, though, lead was often called white lead so people could distinguish them.

00:25:24
Speaker 3: Okay, but the.

00:25:25
Speaker 2: Word plumbum plumbum, does that sound like anything to you?

00:25:30
Speaker 3: Like plumbing, yes, and plumber.

00:25:34
Speaker 2: Yeah, lead was used in Roman water pipes, so that's how plumbing and plumber got their names.

00:25:41
Speaker 1: Oh man, I never even put that two and two together.

00:25:45
Speaker 2: I know. So it prefers like plumbing refers to the actual metal, which was lead, that was used to construct those pipes.

00:25:53
Speaker 3: Wow.

00:25:54
Speaker 2: Isn't that Like my mind went just like dropped out of the back of my head.

00:25:58
Speaker 3: Eology is cool, bro it? Yeah, I love it.

00:26:03
Speaker 2: And you can also find literary references to lead, most of them using lead to describe something as being weighed down like a heart of lead, as well as expressions like I'm gonna pump your guts full of lead, like because angels of dirty souls. Yes, and then there's the word plum itself plumb, which means upright or level, and that comes from the fact that historically people would use lead tools like a plum bob to get a true vertical line.

00:26:32
Speaker 3: WHOA, I didn't know that.

00:26:35
Speaker 2: It's so cool, Okay, But this isn't the history of lead. This is the history of lead poisoning. And it turns out that that reaches back almost as far as the use of lead itself, which is unsurprising. Yes, descriptions of lead poisoning date back basically to I don't know, around six thousand years.

00:26:53
Speaker 3: Ago, okay.

00:26:54
Speaker 2: And these descriptions, yeah, really long time. And these descriptions didn't necessarily identify as the source of the symptoms it could.

00:27:02
Speaker 3: It was more just.

00:27:03
Speaker 2: Describing somebody who had clearly a case of acute lead poisoning. But some actually did make the connection between lead exposure and lead poisoning. So some like scrolls from ancient Egypt, for example, discuss the role of lead in intentional poisoning because people would sometimes use lead acetate to intentionally poison people who and lead poisoning in minors in ancient Rome also allowed people to make this connection between exposure and illness. The history of lead poisoning can basically be divided into occupational exposure and then non occupational exposure. So since lead was used in so many ways like making glass or coins or kitchenware or statues or pigments or food additives, or plumbing or roots or gutters or shipbuilding.

00:27:47
Speaker 1: Like literally all the things that humans have ever done or used.

00:27:50
Speaker 2: Ever, everything, everything, then if you were involved in any of these trades, there were tons of ways to get exposed. But the biggest exposure probably happened for miners who would experience acute lead poisoning. So this is where the concept of miasma also probably gained some support because people who spent Yeah, I.

00:28:12
Speaker 3: Never even thought about that, Because these people who.

00:28:15
Speaker 2: Spent a lot of time in or near mines which were also located in geographically or geologically very specific areas probably got sick.

00:28:24
Speaker 3: Oh my gracious, isn't that cool? Yeah, not cool for them, but very interesting. It's very interesting.

00:28:32
Speaker 2: And there was so much lead mind historically, and there still is today. I mean it has only gone up over time basically that current estimates though, of the number of workers who were exposed to lead during the Roman Empire was around one hundred and forty thousand people per year. So what Yeah, lots of lead exposure. That was just in lead miners. So even if you weren't a lead miner, though, there were plenty of ways that you could encounter enough lead to experience acute or chronic lead poisoning, and ancient Rome was not the only place that you had a high chance of getting that. In China, for example, cookwar had a super high content of lead. So some ancient bronze vessels contained over thirty percent lead. If you cooked anything in those, like, it's just going to leach out into your.

00:29:20
Speaker 1: Food, calling it bronze and it's mostly lead.

00:29:23
Speaker 2: Yeah, And drinking vessels were also made of lead or lead alloys. Lead tumblers have been found in graves dating back to three thousand BCE. And let's throw an ancient Egypt into the mix as well. Wow, but ancient Rome is infamous for their use of lead in like all facets of life. So if your veggies weren't sweet enough, no problem, just cook it in a lead pot or add lead acetate. You could. You could become exposed by handling lead coins or yarns, many of which were treated with lead salts. Children's toys were made of lead. Candle holders and wickholders made of lead or pewter could be partially evaporated while burning the candle.

00:30:07
Speaker 3: And then there's.

00:30:08
Speaker 1: I'm sorry, real quickly, does lead make your vegetables taste sweeter?

00:30:15
Speaker 3: Yes? I'm still stuck on that.

00:30:16
Speaker 2: So like lead acetate was a common or like something called Roman sapa.

00:30:21
Speaker 3: I think something like that.

00:30:22
Speaker 2: It was basically like you added for some reason, adding lead acetate and made things sweeter, like it imparted a sweet taste.

00:30:32
Speaker 3: Oh that is horrible.

00:30:33
Speaker 2: Oh yeah, well just wait, I mean here, so yeah, okay. And then there's lead paint of course, lead in cosmetics or hair dye. And then there's the medicinal uses of lead. So lead was prescribed to remove scars, to curb nocturnal emissions. I don't know how exactly to.

00:30:54
Speaker 3: And have some guesses, but I don't think they're right to this one is horrific.

00:30:59
Speaker 2: To heal the belly button of a newborn after the umbilical cord has fallen off.

00:31:03
Speaker 1: Oh no, you don't need to heal that.

00:31:06
Speaker 3: No, nope. The good is supposed to be there to.

00:31:11
Speaker 2: Help scorpion stings, for preserving your singing voice in contraception.

00:31:17
Speaker 3: So get this.

00:31:18
Speaker 2: You were supposed to smear a honey and cedar and lead mixture on your cervix before having sex.

00:31:25
Speaker 3: Okay, so many issues with that.

00:31:27
Speaker 2: Oh my goodness, even just honey and cedar alone. Don't smear anything on your service.

00:31:33
Speaker 3: Don't smear anything on your cervix, please, my goodness.

00:31:39
Speaker 2: Lead was also used to soften tumors as i medicine and to heal anal fissures. Oh no, Aaron, I feel like these are one hundred percent all problematic. Yes, and uh so for these things, you know. For some of these medicinal uses, lead lotion was great, while sheets of lead were used for others. And then so our quarantini is asangria the bases red wine. Lead was used in wine making for centuries and centuries, so it could be used to stop fermentation or to add color or sweetness. That's why we decided to have asangraa for this one. And then there's the lead pipes of ancient Rome. So in ancient Rome, water pipes were made of lead, and this lead sorry, and this led to an interesting health disparity, kind of the opposite of the one that we see today. So those who were wealthier often had more access and exposure to lead, like having lead water pipes. So we see some of the most prominent cases of lead poisoning in richer populations and among the aristocracy. Interesting later investigation, archaeological and anthropological investigation of sort of ancient Roman water pipes shows that the water was constantly it wasn't sitting in pipes ever, the way that it does now, and so there probably wasn't a lot of lead leeching into that water. In addition to the fact that it was probably coded on the inside with like other scaly metals, and so the water itself was more or less protected from the lead in the pipes. But okay, anyways, okay, but so there's been a lot of retrospective diagnosis, which you know, so take this with a grain of salt, of many of the Roman emperors from fifty BCE to two hundred and fifty CE, and that suggests that they were basically all.

00:33:39
Speaker 3: Suffering from too much lead.

00:33:41
Speaker 2: I mean, yeah, I mean, And so I can't go this entire episode without talking about the fall of the Roman Empire, which is why we named our quarantine need thiss So. A few decades ago, a guy named Jerome Noriagu published his hypothesis that the decline of the Roman Empire was caused by widespread lead poisoning, especially among the wine drinking and lead water consuming aristocracy, and that the decreasing fertility and higher rates of psychosis that followed really caused this like massive intellectual and structural decline.

00:34:17
Speaker 3: Wow, this was not the first like this.

00:34:20
Speaker 2: This is kind of an older hypothesis, but when he published his paper, it gained a lot of attention, and there's been a ton of response papers, either in support or more often refuting this hypothesis. Studies examining the amount of lead in ancient Roman bones show similar lead levels as in modern populations. Interesting or modern populations have higher lead which is yeah ye, And in general, this hypothesis doesn't really have a lot of widespread support anymore. So lead poisoning may have contributed, but it probably wasn't the main cause.

00:34:56
Speaker 3: Multifactorial let's say.

00:34:58
Speaker 2: Yeah, but despite this, we decided to perpetuate the false notion by naming our quarantining the Fall of Rome.

00:35:07
Speaker 3: So it's good name still, I know, I like it.

00:35:12
Speaker 2: So we know that people were likely experiencing acute chronic lead poisoning based on how much lead they used, but when did they start making the connection between exposure and illness? And that would have been really difficult to do because lead poisoning can manifest in so many different ways, especially with chronic low level lead poisoning. Yeah, there do seem to be reports of epidemic or pandemic lead poisoning, which were often called pandemic attacks of colic, the first of which was sometime during the seventh century CE, and these pandemics continued until around the sixteenth century, when a German physician figured out it was linked to wine that was supplemented by lead. And so from that point onwards, a lot of countries were like, no, you cannot use lead in wine making anymore, and so that probably in some ways lowered chronic lead exposure, but obviously it was still around. It was just like one tiny little area of life. So in cosmetics, for example, people used to use it to as like a paste to hide smallpox scars and just to make themselves prettier.

00:36:20
Speaker 3: Gosh.

00:36:20
Speaker 2: But the problem with topical lead application is that it poisons you. So many people who wore this lead based concealer would end up with ruined skin and hair loss. And this led to a fad in Elizabethan times of shaving the front of your hairline.

00:36:37
Speaker 1: Are you serious, I'm serious, that's because of lead.

00:36:41
Speaker 3: Yeah, you've seen those.

00:36:43
Speaker 1: All the pictures of them was like no hair, Oh my gracious yeah.

00:36:48
Speaker 2: According to this book I read, yeah, wow, okay. And so, even though the dangers of lead were known, cases of acute lead poison and continued to her Apparently, lead poisoning from rum could be quite an issue depending on where the rum was aged, and the Industrial Revolution basically ensured that everyone, everyone, whether you worked with lead or not, would be exposed to lead. And this period marks a kind of shift in the history of lead poisoning. So, up to this point, acute lead poisoning was definitely recognized, but low levels of lead poisoning weren't really thought.

00:37:25
Speaker 3: To be harmful, even though they very much are.

00:37:29
Speaker 2: In the late eighteen hundreds and into the nineteen hundreds, the focus on at risk populations for lead poisoning shifted from people who worked with lead to children who, as you mentioned for all of those reasons, are high risk. Chronic lead poisoning and children was first recognized in the late eighteen hundreds in Australia, but it was met with complete disbelief. Yeah, lead had been around, people have been using it.

00:37:51
Speaker 3: For ages, can't be bad. Yeah.

00:37:55
Speaker 2: It would take until the nineteen twenties for lead based paint to be banned in Australia and in much of Europe, and another fifty.

00:38:02
Speaker 3: To sixty years after that for it to be banned in the US.

00:38:06
Speaker 4: Wow.

00:38:07
Speaker 3: So doing great, doing great. Alkay. For the last bit of.

00:38:12
Speaker 2: This history section, I wanted to focus on childhood lead poisoning in the US because it's really well documented sort of the history and the politics surrounding it, and I think it's such a perfect example of how politics and public health are intertwined.

00:38:28
Speaker 1: Oh, Aaron, this is gonna be a political episode.

00:38:32
Speaker 3: I mean until the epidy meology. Oh here we go.

00:38:37
Speaker 2: Okay, So first I want to set the stage a little bit because the presence and persistence of lead poisoning throughout today is just part of a long held trend in ignoring the systemic problems in pollution, poor housing, water infrastructure, et cetera that cause huge health disparities. Over the past let's say, two hundred years, there have been huge improvements in the overall health of the world world, due in part to the advancements in knowledge about how infectious diseases are transmitted and how chronic diseases can be caused or worsened by some environmental contaminants.

00:39:10
Speaker 3: But it was.

00:39:11
Speaker 2: Really public health efforts focusing on groups of individuals or improving infrastructure that led to those improvements, rather than physicians treating the individual So things like vaccine campaigns and improved housing and workers' rights and clean food and water legislation, these things treated the underlying cause of many illnesses rather than the illness itself, and prevention saves much more than treatment after the fact.

00:39:37
Speaker 3: An ounce and ounce a pound, etc. Yeah, exactly.

00:39:42
Speaker 2: And for a long time, from the late eighteen hundreds to the mid nineteen hundreds around there, maybe of these systemic improvements really did help improve overall health, but at some point that focus sort of switched from treating groups of people or treating the underlying issues to treating the individual who is disa and reducing overall exposure, but not prevention in terms of like there was not a lot of push for improving housing quality or water purity, and those were the things that disproportionately affected people living at or below the poverty line.

00:40:14
Speaker 3: Yeah, okay.

00:40:16
Speaker 2: Lead, So even though it was known that lead was bad, the use of lead actually increased in the twentieth century. It was added to gasoline to give the cars more power, it was in paint to help the walls shine. Throughout the mid twentieth century, the US interstate highway system greatly expanded, which allowed for the deposition of lead in soils basically all over the country. And it's not like people hadn't thought of the potential danger of this leaded gasoline. As early as the nineteen twenties. People had expressed their concern, but the Lead Industries Association funded scientific research specifically to come to the conclusion that lead was a natural part of the human environment, and humans had been working with lead for thousands of years.

00:41:03
Speaker 3: It was safe.

00:41:04
Speaker 1: People have been working with lead for thousands of years. People have been dying from lead for thousands of years. Yea, oh, my gosh, the nineteen twenties, that was.

00:41:12
Speaker 2: Yeah, I mean as early as the nineteen twenties the dangers were known, but there was already pushback from the Lead Industries Association.

00:41:18
Speaker 3: Yeah, oh my gracious, And so this was their line.

00:41:22
Speaker 2: This was their stance for the next four decades, basically actually beyond that, until it was overturned by the overwhelming evidence that any lead exposure at all was harmful. But by then so much damage had been done and it's still being done. So Around the nineteen forties, physicians and researchers in the US started to become aware that lead poisoning, both chronic and acute, could lead to long term damage, so that children who presented with signs of acute lead poisoning and then recovered would probably never recover completely, but would always carry effects like developmental delays, behavioral problems, learning disabilities on. Citywide epidemics of lead poisoning in children in the nineteen fifties were seen in places like Chicago, Baltimore, New York City, Cincinnati, and Saint Louis, and these brought greater attention to the issue that lead based paint caused. But the lead Industries Association fought against these negative portrayals of lead. They embarked on or continued their propaganda machine about how much better lead was than any other material for pipes and paint and gasoline. They downplayed or outright denied the reports of widespread lead poisoning, often making fun of the victims or putting the responsibility on the parents and the child who had lead poisoning, saying, well, they should have been watching the kid more.

00:42:41
Speaker 3: Oh my gracious.

00:42:43
Speaker 2: They took the line that if it didn't affect the health of the average person, then it wasn't worth changing.

00:42:49
Speaker 1: And their definition of the average person.

00:42:52
Speaker 2: Is going to be a wealthy person who's above poverty line, white person exactly. And so this resils distance to do anything about lead obviously slowed down the social reform that was needed to actually help fix the issue of lead everywhere. In nineteen sixty seven, a physician named Jane Linfu published a widely circulated booklet that discussed the issue of lead, particularly lead based paint, and it did largely ignore the effects of gasoline and other exposures which weren't as recognized. That was sort of the standard of the time. But she framed this lead poisoning. This chronic led exposure as a public health issue, which some public health officials took exception to, saying that, no, this is a housing issue, not a matter of public health, and this was this unnecessary divide that would slow down progress for a really long time.

00:43:42
Speaker 3: Oh my god, that's infuriating.

00:43:45
Speaker 2: Well, it's a difference of labeling, and it's a difference of we don't want to be responsible for this.

00:43:49
Speaker 3: This isn't on us. Yeah.

00:43:52
Speaker 2: And so even though people clearly recognize that low levels of lead post a health problem, by the nineteen seventies, the magnitude of the problem wasn't as well known. Aaron, So you know the en Haines Survey, Yes, ado, Okay. So n HAYES stands for National Health and Nutrition Examination Survey, and basically its purpose is to document the health of the American people. So they measure all kinds of things. It's been amazing in terms of like monitoring exposures, health status, whatever.

00:44:23
Speaker 3: In nineteen seventy six, blood.

00:44:25
Speaker 2: Lead levels were included in the survey for the first time, and they revealed that one out of every twenty five kids between the age of six months and five years had blood lead levels greater than thirty micrograms per desto leader.

00:44:39
Speaker 3: WHOA WHOA Yeah.

00:44:41
Speaker 2: Based on the US population at that time, that calculates to around seven hundred and eighty thousand children under six years old that had lead poisoning.

00:44:50
Speaker 1: Thirty at thirty and that's really high.

00:44:53
Speaker 3: That's very high.

00:44:55
Speaker 2: And then there were enormous racial, locational economic differences in terms of the rate of lead poisoning as well. So while only two percent of white children had elevated blood lead levels, twelve point two percent of black children had elevated blood lead levels, and urban children fared worse than rural children eleven point six percent to two point one percent. In families whose combined income was fifteen thousand dollars or more so, which is like, I don't know, around thirty five to forty thousand dollars in nowadays money, one point two percent of children were affected, while in families who with a combined income of less than fifteen thousand dollars in nineteen seventy six, so less than thirty five to forty thousand dollars. In those families, ten point nine percent of children had elevated blood lead levels. Lead poisoning basically.

00:45:49
Speaker 3: Yeah, so okay.

00:45:53
Speaker 2: The early nineteen seventies also saw the emergence of another big lead researcher, Herbert Needleman, whose pioneering work on low lead level exposure would revolutionize our understanding of the risk.

00:46:06
Speaker 3: Right.

00:46:07
Speaker 2: In one study, he compared the lead level in baby teeth from children in suburban homes and in poor communities, and he found that those in the poor urban communities had almost five times the amount of lead compared to the ones in the suburbs.

00:46:20
Speaker 1: I also will say it's so genius to start using baby teeth as the level, because, like I said earlier, the levels in your blood can change much more rapidly than the levels in your teeth, and often you're testing kids that are older when the exposure happened when they were a lot younger. So it was very genius to use baby teeth.

00:46:40
Speaker 3: Yeah.

00:46:40
Speaker 2: This research was groundbreaking because it also showed that even at low levels of lead exposure, levels that were considered safe by the CDC, there were still observable long term effects of lead exposure.

00:46:52
Speaker 3: Yeah.

00:46:53
Speaker 2: Obviously, the lead industry did not like this shocking, and they brought on basically just like paid money to a prominent LED researcher whose primary purpose, it seems, was to discredit Needleman's studies and any other study showing that low level LED exposure was dangerous.

00:47:14
Speaker 3: This seed of doubt actually had.

00:47:16
Speaker 2: An influence on government decisions and regulations by the EPA, which is hugely worrying but also not surprising, especially considering climate change and stuff today. So this is a great example of how politics and public health become enmeshed, especially when the government gives equal forum to both the industry whose livelihood depends on the outcome of these studies. So this enormous conflict of interest in the scientists who are reporting their findings as objectively as humanly possible.

00:47:45
Speaker 3: Oh gracious.

00:47:47
Speaker 2: Even when a conflict of interest is clearly declared, it can still be hugely damaging once that seed of doubt is planted, all right. So, because lead poisoning was labeled as a housing problem, back to this issue, it became inherently politicized, especially in the nineteen eighties and into the nineteen nineties, where proposed lead elimination or prevention policies were labeled as leftist politics and social engineering. By this time, the scientific consensus was clear there was no safe level for lead exposure. Leaded gasoline was no longer used, and lead based paint had been banned as of nineteen seventy eight, but the risks of exposure were far from over. It wasn't like, oh, we ban these, so now no one's going to get exposed. Yeah, soil was chok full of lead around highways. Lead based paint is still You have to sign waivers anytime you move into a house that was built before nineteen seventy eight.

00:48:41
Speaker 1: My house was built in nineteen twenty nine, so yeah.

00:48:44
Speaker 3: Jeez, yeah, yeah.

00:48:47
Speaker 2: Millions and millions of houses or buildings had lead based paint, and abatement was extremely expensive and carried its own risks. So the dust created during the abatement process and even during everyday living by spitting a window with lead based paint trim could reach poisoning levels. Conservative estimates for the complete removal of lead based paint from the sixty four million federally owned housing units it was around ten thousand dollars per unit in nineteen ninety dollars.

00:49:15
Speaker 3: Ooh wow.

00:49:17
Speaker 2: So many landlords and the government also basically was like either going, We're either going to abandon ship, or we'll just ignore the problem completely.

00:49:27
Speaker 3: It's a lot easier than fixing it. Yeah, it's a lot easier than fixing it.

00:49:31
Speaker 2: And it's a lot cheaper because if you let's say you were a landlord and you were required to do lead based paint abatement and you didn't do it, you could be taken to court, which could take months or years, and then you're like, oh, here's a four hundred dollars fine, Like that's I'm sorry, four dollars fine. I don't know if that's exactly what it was, but it wasn't. That wasn't ten thousand dollars, right, And so, seeing this huge task in front of them, the public health approach switched from risk prevention to risk reduction. How can we most cheaply do lead based paint abatement was like the bottom line, and it's sort of putting a price tag on the health of the American children. It's outrageous, okay, and in walks the Kennedy Krieger Institute Study on lead based paint.

00:50:17
Speaker 3: Have you heard of this?

00:50:18
Speaker 1: No?

00:50:18
Speaker 3: I haven't, Okay.

00:50:19
Speaker 2: In nineteen ninety one, this institute began a study that would eventually be compared to the Tuskegee syphilis experiment that I talked about in our Syphilis episode, where poor black men were preyed upon by researchers to.

00:50:31
Speaker 3: Study the effects of on trades of lists.

00:50:34
Speaker 2: This lead based paint study, which began in nineteen ninety one, oh No. Nineteen ninety one, oh No, involved one hundred and eight families of single mothers with young children. The researchers placed these families in houses with varying levels of lead, from no lead to lead levels just within Baltimore's legal limit.

00:50:55
Speaker 1: I'm sorry they put people in houses with lead lead. Yes, in nineteen ninety one. Yes, single moms okay, single moms great.

00:51:06
Speaker 2: And then they would try out different kinds of lead based paint abatement while periodically monitoring the blood lead levels in the families.

00:51:13
Speaker 3: Their goal was.

00:51:14
Speaker 2: To find the most cost effective way to reduce lead based paint. So how cheaply could you achieve lower lead levels in the blood using children as biological monitors?

00:51:24
Speaker 3: Oh? Oh my god, Oh my god, oh my god. I know.

00:51:30
Speaker 2: The researchers, of course acknowledge that no lead based paint would be the best level, but they argue that most landlords would abandon the houses if required to shell out a bunch of money on lead based paint abatement, and so then these people would be would continue to live at dangerous levels. So their argument was, well, we're taking them out of houses with potentially worse lead conditions and hoping to use this knowledge to help everyone everywhere.

00:51:57
Speaker 3: Just some just some tiny children, guinea pigs, A big deal.

00:52:01
Speaker 2: Yeah, it's appalling. So this was human experimentation, and the despite their intentions, the researchers knowingly placed children in homes where they knew they could be exposed to potentially dangerous levels of lead.

00:52:15
Speaker 3: Because any lead exposure is dangerous.

00:52:18
Speaker 2: Yep, and this was well known by the nineteen nineties.

00:52:20
Speaker 1: Nineteen of course it was are you oh l Aaron, I'm raging.

00:52:26
Speaker 3: I know, I know me too.

00:52:27
Speaker 2: So when this study came to light in the late nineteen nineties, the researchers were taken to court and the court found that they had engaged in unethical research that defied many aspects of the Nuremberg Code and bore similarities to Nazi experimentation, which are it's strong language. Yeah, but it is still appalling.

00:52:48
Speaker 3: What I approved this quite honestly, well right, I mean, but they did get IRB approval, of course they did. It was then it's very concerning. It's very concerning. Yeah, wow.

00:52:58
Speaker 2: And these are the two people who led the study, were renowned LED researchers and children's health advocates. So it's a there's much more discussion about this case, this experiment itself, and the court battle and so on in the book led Wars, so I encourage people to look into it.

00:53:18
Speaker 3: But still the.

00:53:19
Speaker 2: Bottom line is that in this experiment, and as it continues today, children are being used as like canaries in the mind or these biological monitors for lead content, and a society is measured by its treatment of its children.

00:53:34
Speaker 3: So the first hand.

00:53:35
Speaker 2: Account features a boy who experienced acute lead poisoning, which was treated by the doctors and nurses that he saw, but they could only help treat him, not the underlying problem. The hospital had no ability to intervene with the landlord's failure to repair the home. This is something that still happens today, and in the words of the authors of led Wars, John who was the kid from the first hand account, was differing from more than an environmental exposure to a known neurotoxin caused by shoddy landlords and peeling paint. He suffered from a social and economic system that condemned his family to poverty and racial discrimination, as well as the urban decay that put him in harm's way. What John experience was acute lead poisoning, which fortunately has been largely controlled in the US over the past century, but chronic lead poisoning caused by long term exposure to low levels of lead is still a huge problem. Look at the Flint, Michigan water crisis for example, Look at many cases of this all over the US, all over the world, there have been so many large scale lead poisoning epidemics, often associated with like lead smelters. There was one, for instance, in Nigeria in twenty ten that has caused the deaths, the deaths of at least four hundred children. Oh, it's still ongoing, this issue, my god.

00:54:55
Speaker 3: Yeah.

00:54:56
Speaker 1: Ugh, it's so infuriating because it's so preventable.

00:55:00
Speaker 2: Yeah, And the problem of led exposure can't be solved with just a medical intervention. If there's going to be any lasting change, there has to be reform at a systemic level. The issue of lead exposure and other environmental or occupational hazards. Is a perfect example of how politics and public health have to go hand in hand. The people who are in power and can make these changes are elected officials. They're not the ones at risk for lead poisoning, and they'll never be because they can afford not to be. And then to get any movement on that front, public health officials might push for more easily digested regulations, like redefining what an acceptable level of exposure is, but that undermines the credibility of public health. When presented with the suggestion that complete abatement of lead based paint was the only way to end the issue of lead poisoning, many elected officials dismiss it out of hand as a utopian dream. This viewpoint just perpetuates the cycle of poverty. Erin on that note, tell me where we stand with lead poisoning today.

00:56:04
Speaker 1: Oh, let's talk about it, Aaron Ooh, I need a quick break after that.

00:56:08
Speaker 3: Yeah, okay.

00:56:34
Speaker 1: First off, did you know that elevated blood lead levels were the first non infectious notifiable condition.

00:56:41
Speaker 3: In the US. No, I didn't know that. I neither nineteen ninety five or ninety six. Oh my God, that seems really late.

00:56:48
Speaker 1: It is very recent, even like my youngest brother was born by then, so yeah, it's wow.

00:56:57
Speaker 3: So yeah.

00:56:58
Speaker 1: Anyways, it used to be that elevated blood levels of lead were only considered when you had a blood level over sixty, since that's when the clinical symptoms are most commonly seen. Right, But at some point, I think it was in the nineteen seventies that level was decreased to ten and that was considered the safe limit. But since twenty twelve, the way that it works is there is no safe limit. I mean, we knew this from before, but since twenty twelve, there is no longer anything considered a safe limit or even a level of concern. So now what they use the CDC uses a blood lead reference value. So what that means is that they look at the blood using the en Haines data that you talked about, they estimate the average blood lead level among children in the US, and the highest two point five percent of children. That cutoff value is what they use to cons elevated.

00:58:01
Speaker 3: Does that make sense?

00:58:03
Speaker 1: Yes, so right now in twenty nineteen, that level is five five micrograms per desoleader is considered quote elevated that's what the elevated lead level is considered.

00:58:15
Speaker 3: Now.

00:58:16
Speaker 1: The CDC's push is every four years they reevaluate that and they want to get it down to as low as humanly possible. Right, that's the goal. Yeah, so that no child is exposed to any level of lead.

00:58:29
Speaker 3: That's the goal.

00:58:31
Speaker 1: Worldwide, According to the WHO, which cited the Institute for Health Metrics and Evaluation, I hadn't heard of that institute before, but they estimated that in twenty seventeen, lead exposure across the globe accounted for one million deaths in twenty seventeen and twenty four point four million years of healthy life lost.

00:58:56
Speaker 3: I just got chills.

00:58:59
Speaker 2: Yeah, that is so that it's such an incredible loss of life and life years and yeah wow.

00:59:08
Speaker 1: The highest burden, unsurprisingly, is in low and middle income countries. They estimated that in twenty sixteen, lead exposure accounted for sixty three percent of the total burden of intellectual disability across the globe. Oh my gosh, ten percent of hypertensive heart disease, which nobody thinks about being associated with lead, but like we talked about, the effects of lead on your kidneys can have major effects on your blood pressure and blood pressure just destroys your heart having high blood pressure. Yeah, and then also five percent of the global burden of ischemic heart disease, so that's when you have clots in your blood. That means your blood, your heart isn't getting enough blood. And six percent of the global burden of strokes as well, a lad it's led. Yeah, that's worldwide.

01:00:07
Speaker 3: And this is something that like it's not getting any better, not fast enough, that's for sure.

01:00:13
Speaker 1: Yeah.

01:00:14
Speaker 2: Yeah, it's going to take decades because like you said that that I'm still stuck on the whole leaching out of your bones over time, like a slow drip of poison.

01:00:23
Speaker 1: Right, Yeah, it's terrifying. So in the US, of course, it was Flint, Michigan that brought lead poisoning back to the front page news. We can't have an episode about lead poisoning and not talk about the situation in Flint, Michigan.

01:00:38
Speaker 3: Yeah.

01:00:39
Speaker 1: In twenty fourteen, if you don't know the story of Flint, maybe you don't live in the US, because I feel like, I don't know how you could live here and.

01:00:46
Speaker 3: Not have heard about this, right. Yeah.

01:00:49
Speaker 1: In twenty fourteen, the city of Flint decided to switch from using Lake Huron and the Detroit River as their water source to the Flint River because it was going to be a lot cheaper. However, the water in the Flint River was more corrosive and they did not take that into consideration whatsoever. And most of the pipes in Flint were lead pipes. The pipes that lead into people's houses water pipes made of lead. So, first of all, I mean, this was such a disaster. It's too big of a topic to even talk about in a lot of detail because the situation in Flint was managed horribly. It was so severe. Tens of thousands of homes were affected, and it took literally years for people to gain access to safe water.

01:01:43
Speaker 2: Again, even though many people now have access to safe water, the effects of that lead exposure is still lingering in.

01:01:51
Speaker 1: That way, exactly like children in Flint are going to be affected for the rest of their lives because of this. It was and remains a terrible, horrible situation. But here's the thing, It's not just Flint.

01:02:06
Speaker 3: Oh No.

01:02:07
Speaker 1: A study in twenty seventeen estimated that one point two million cases of blood lead levels over ten micrograms per desolator, which is twice what's considered elevated today?

01:02:20
Speaker 2: Right? If you shifted that to five, what would that right?

01:02:23
Speaker 3: Yeah?

01:02:23
Speaker 1: One point two million cases occurred in children between the years nineteen ninety nine to twenty ten.

01:02:30
Speaker 3: Wow.

01:02:31
Speaker 1: However, only six hundred thousand of those were reported. So that means that half potentially of children who have elevated blood levels of lead, no one is reporting that, which means we don't know, which means they're not getting treatment, yeah, or having their exposures reduced because we don't know.

01:02:52
Speaker 3: About their exposures. Oh my gosh.

01:02:54
Speaker 1: And like you said, that's at an elevated blood level of ten micrograms. Five is can considered elevated, So who knows what that number is if you consider it to be five micrograms?

01:03:05
Speaker 3: Yeah.

01:03:07
Speaker 1: The problem, there's many problems, but a large part of it is that most children are never tested for their blood blood levels. It's not required by the federal government or by state governments.

01:03:18
Speaker 3: Huh.

01:03:18
Speaker 1: It is only required to test children who are medicaid beneficiaries, but in reality, less than half of those children are even actually tested. So those are the children that we know are likely the most vulnerable, and only half of them are being tested and the rest of the children in the US not even tested.

01:03:38
Speaker 3: Wow.

01:03:39
Speaker 1: So people sometimes tell us to stop being so political and stick to science. On this podcast, there's no such thing. There is absolutely no such thing. There are at least two big risk factors that we know that massively increase the risk of lead exposure in children. The age of the house in which they live, right, because that's lead paint exposure, and poverty, because poverty is the biggest risk factor.

01:04:10
Speaker 3: Right.

01:04:11
Speaker 1: There are some really great maps, Vice and Vox, both the news outlets Vice and Vox made maps. So the Vox map especially, is every census tracked in the entire country. It was Vox plus the Washington Department of Health. They estimated the risk of lead exposure based on those two risk factors, the age of houses and the level of poverty in the area, to estimate the level of lead exposure risk across the whole country. Okay, h We'll put a link to those maps on our website. They're really interesting. You should check them out. Here's the thing about when you look at those maps, Aaron, We're gonna roll reverse and I'm gonna tell.

01:04:51
Speaker 3: You some history.

01:04:53
Speaker 1: Oh great, in the nineteen thirties, after the Great Depression, the Homeowner's Loan Corporation was requested to make maps of cities to assess the riskiness of mortgages for lenders to try and get lenders back to lending to people to buy homes to like fix the Great Depression or whatever.

01:05:13
Speaker 3: Okay, these maps are.

01:05:18
Speaker 1: Outrageously racist, of course. So what they did was outlined in red hence the term redlining the most undesirable or hazardous neighborhoods. From a mortgage lending perspective, guess what neighborhoods were redlined? Neighborhoods where black people lived, period. And the descriptions of why certain neighborhoods were redlined, like you can read these descriptions. They were labeled as high risk if a single black.

01:05:49
Speaker 3: Person lived in that neighborhood. Oh my god, that was it.

01:05:53
Speaker 1: So guests who didn't get home loans people who lived in those neighborhoods aka black people.

01:05:59
Speaker 3: Okay.

01:06:00
Speaker 1: So this led to continued improverishment of those areas that persists today. If you look at maps today of areas that are still where the median household income is lower than what is average for the country, it's still those red lined areas.

01:06:15
Speaker 3: Wow.

01:06:16
Speaker 1: Now, if you overlay the maps of current LED exposure risk and the red line maps from the nineteen thirties.

01:06:24
Speaker 3: They match up. Of course they do.

01:06:27
Speaker 1: The areas where people are still being exposed to major health risks are directly because of systemic, outright racism in this country.

01:06:37
Speaker 2: This is why, like there's no separation of public health and politics, between science and politics. Like it's inherent to this, and I mean, I wish that it weren't. I wish that it would be. Here's this problem, we have the money to fix it. Let's fix it.

01:06:53
Speaker 3: But it's not that because.

01:06:55
Speaker 2: There are the interests of the industries at play. There's these political parties who are backed by the industries. It's everything is so interwoven that it's impossible to talk about it.

01:07:06
Speaker 3: In a vacuum. Yep.

01:07:07
Speaker 2: And it's not effective to talk about it in a vacuum.

01:07:10
Speaker 3: No, it's useless. There's no context.

01:07:13
Speaker 2: You have to have the context, the historical, the political, the social context to understand why disease happens where it happens yep.

01:07:22
Speaker 3: Exactly.

01:07:24
Speaker 1: So that's the state of lead poisoning in the world, and especially in the US.

01:07:30
Speaker 3: Today.

01:07:30
Speaker 1: While we have seen major reductions overall in the blood lead levels of children in the US, the health disparities cannot be ignored. People who live at less than one hundred and thirty percent of the federal poverty level are more than twice as likely to have elevated blood levels. Black children are more than twice as likely to have elevated blood led levels than white children.

01:07:54
Speaker 3: Like, it's it's very bad.

01:07:58
Speaker 1: It's not a problem is isolated to just one city. It is not a problem that is isolated to just a few areas. It's rampant across the country no matter where you live.

01:08:08
Speaker 3: Mm hmm, yeah it is. So that is.

01:08:13
Speaker 1: Lead poisoning erin Wow, yeah it is.

01:08:20
Speaker 2: Well then, so, yeah, this was a very heavy episode, heavy metal episode. Huh.

01:08:27
Speaker 3: Sorry that was funny, but it is.

01:08:31
Speaker 2: I mean, it's it's it's a hugely important topic.

01:08:34
Speaker 3: Yeah.

01:08:34
Speaker 1: I think a lot of people think that lead poisoning like Flint, Michigan made the news because it was so egregious. The water that was coming out of people's taps was clearly contaminated and people were being exposed to levels of lead dozens of times. The you know, there is no safe level, but extremely high.

01:08:53
Speaker 3: Levels of lead.

01:08:54
Speaker 1: Right, yeah, and so that's I think why it made such news because it was massive and and thousands of children and adults. They haven't even tested the levels of blood in adults in flint, which is atrocious. Right, Hundreds of thousands of people are likely affected from this, and that deservedly made the news. But children are being affected by this every day, and people don't even realize that it's still a thing outside of these headline grabbing situations.

01:09:24
Speaker 2: It's a huge thing and it's not going to go away anytime soon.

01:09:28
Speaker 3: But it's such a.

01:09:29
Speaker 2: Problem because the people who are the most affected by it don't have a voice to do anything about it. And that's just part of you know, the disenfranchisement of entire groups of people because they live below ad or below the poverty line, systemic racism, all of these things.

01:09:45
Speaker 1: Yeah, yeah, yeah, But you know, let's not get political, Aarin, Let's stick to our lane.

01:09:53
Speaker 3: Do you have any sources.

01:09:54
Speaker 2: Yeah, we're scientists, not politicians, so we should only talk about science.

01:09:59
Speaker 3: Okay. I read a couple of books.

01:10:03
Speaker 2: One is called Lead and Lead Poisoning in Antiquity, So that's where I got a lot of the Ancient Roman stuff and then led Wars, The Politics of Science and the Fate of America's Children by Gerald Markowitz and David Rosner. This book was great. I highly recommend it. And then I also read some papers that I'll post a few by needlemen of course, and we'll post all of these on the website.

01:10:30
Speaker 1: Yeah, if you would like links to the Vox map that was made by both Vox and the Washington Department of Health, we will post that link as well as if you're interested in those redline maps, the University of Richmond has online interactive all of the maps that were made during that redlining time where you can see exactly what areas were redlined and the descriptions on why they were redlined.

01:10:59
Speaker 3: I need to read this. Can you see this? It's very it's very horrifying.

01:11:04
Speaker 1: So as always we'll post the links to all of our sources on our website. This podcast will Kill You dot Com. Just click on episodes and you can see the sources from this episode and all of our episodes.

01:11:15
Speaker 2: Thank you to Bloodmobile for providing the music for this episode and all of our episodes.

01:11:19
Speaker 1: And thank you, dear listeners for listening to this podcast, allowing us to make it and getting righteously angry right along with us. Heck yeah, well with that, wash your hands you feel the animals