1 00:00:00,920 --> 00:00:04,040 Speaker 1: Welcome to How Stuff Works Now. I'm your host, Lauren Vogelbam, 2 00:00:04,200 --> 00:00:10,959 Speaker 1: a writer in researcher. Here at How Stuff Works. Every week, 3 00:00:11,039 --> 00:00:13,480 Speaker 1: I'm bringing you three stories from our team about the 4 00:00:13,560 --> 00:00:16,920 Speaker 1: weird and wondrous developments we've seen in science, technology, and 5 00:00:16,960 --> 00:00:20,960 Speaker 1: culture today. Even babies know not to trust gifts from 6 00:00:20,960 --> 00:00:25,240 Speaker 1: shady characters up to a point, and robots smaller than 7 00:00:25,280 --> 00:00:27,440 Speaker 1: the width of a human hair could be the solution 8 00:00:27,440 --> 00:00:30,280 Speaker 1: to getting toxic lead out of our water supply. But 9 00:00:30,440 --> 00:00:34,120 Speaker 1: first I dig into why lead contamination is an increasing 10 00:00:34,159 --> 00:00:36,960 Speaker 1: problem in the United States and why it's so harmful 11 00:00:36,960 --> 00:00:42,080 Speaker 1: to begin with. When you turn on your faucet, your 12 00:00:42,080 --> 00:00:45,040 Speaker 1: the final destination, and a water droplets incredible journey through 13 00:00:45,080 --> 00:00:48,360 Speaker 1: regional and local water supply systems. That drop typically has 14 00:00:48,400 --> 00:00:51,000 Speaker 1: gone from source to treatment plant, to pump station, to 15 00:00:51,080 --> 00:00:54,120 Speaker 1: water tower, to water maine to local distribution lines to 16 00:00:54,200 --> 00:00:56,639 Speaker 1: get to you here in the United States. A lot 17 00:00:56,680 --> 00:00:59,440 Speaker 1: of that infrastructure was built immediately after World War Two, 18 00:00:59,720 --> 00:01:02,320 Speaker 1: and some of it even dates to the late eighteen hundreds. 19 00:01:02,560 --> 00:01:04,960 Speaker 1: A few towns in America still have wooden water mains. 20 00:01:05,200 --> 00:01:07,480 Speaker 1: According to the e p A, at least thirty percent 21 00:01:07,600 --> 00:01:09,759 Speaker 1: of our high use drinking water pipes are more than 22 00:01:09,800 --> 00:01:12,839 Speaker 1: forty years old. This aging infrastructure could be a huge 23 00:01:12,920 --> 00:01:16,679 Speaker 1: problem for three related reasons. First, the CDC only started 24 00:01:16,800 --> 00:01:20,720 Speaker 1: establishing acceptable blood lead levels for children in the nineteen sixties, 25 00:01:20,760 --> 00:01:22,840 Speaker 1: meaning that many of our pipes were built before we 26 00:01:22,920 --> 00:01:27,240 Speaker 1: knew exactly how harmful lead is. Second, metal pipes, depending 27 00:01:27,240 --> 00:01:29,119 Speaker 1: on what metal they're made of in the conditions where 28 00:01:29,120 --> 00:01:32,040 Speaker 1: they're laid, can last over a hundred years or as 29 00:01:32,080 --> 00:01:35,959 Speaker 1: little as fifteen. And Third, this infrastructure is literally buried, 30 00:01:36,000 --> 00:01:38,760 Speaker 1: so it's difficult to diagnose issues until something has already 31 00:01:38,760 --> 00:01:42,399 Speaker 1: gone seriously wrong, like in flint, Michigan and sabring, Ohio. 32 00:01:42,640 --> 00:01:46,120 Speaker 1: All metals break down over time through corrosion and dissolution. 33 00:01:46,280 --> 00:01:50,560 Speaker 1: That's right, metals dissolve just very slowly. Water is corrosive 34 00:01:50,600 --> 00:01:54,040 Speaker 1: by nature because it contains dissolved oxygen, and corrosion is 35 00:01:54,040 --> 00:01:56,800 Speaker 1: what happens when metals react with oxygen and break apart 36 00:01:56,880 --> 00:02:00,360 Speaker 1: into particles of metal oxides. This is disastrous for human 37 00:02:00,440 --> 00:02:03,920 Speaker 1: drinkers because lead is so toxic, even at seemingly tiny 38 00:02:04,000 --> 00:02:08,640 Speaker 1: levels of ingestion, it can cause irreversible damage to the liver, blood, kidneys, 39 00:02:08,680 --> 00:02:11,360 Speaker 1: and brain in young children and unborn babies. It's been 40 00:02:11,400 --> 00:02:15,040 Speaker 1: implicated in lifelong behavior and attention problems, reduced i Q, 41 00:02:15,400 --> 00:02:18,440 Speaker 1: delayed growth, and even an increase in violent behavior. Although 42 00:02:18,440 --> 00:02:21,840 Speaker 1: researchers are still studying why these effects happen, the leading 43 00:02:21,880 --> 00:02:25,760 Speaker 1: idea is that atoms of lead displace other atoms and proteins. 44 00:02:25,760 --> 00:02:29,480 Speaker 1: This can seriously reduce or change ensignsufficiency in our bodies, 45 00:02:29,720 --> 00:02:33,040 Speaker 1: causing chains of issues from the cells. Up steps can 46 00:02:33,080 --> 00:02:36,040 Speaker 1: be taken to preserve pipes by controlling waters pH level 47 00:02:36,080 --> 00:02:39,519 Speaker 1: and adding protective compounds like calcium or magnesium salts that 48 00:02:39,560 --> 00:02:42,160 Speaker 1: will coat the pipes and won't harm humans. But every 49 00:02:42,160 --> 00:02:45,360 Speaker 1: water system is different and must be monitored closely, and 50 00:02:45,520 --> 00:02:48,520 Speaker 1: these are all temporary measures. A report from the American 51 00:02:48,520 --> 00:02:52,440 Speaker 1: Water Works Association suggests that updating or water infrastructure will 52 00:02:52,480 --> 00:02:55,360 Speaker 1: cost a trillion dollars over the next twenty years or so. 53 00:02:55,480 --> 00:02:57,120 Speaker 1: But this is one of those cases where the cost 54 00:02:57,160 --> 00:03:00,280 Speaker 1: is unavoidable, and as Flint is finding out, not making 55 00:03:00,320 --> 00:03:09,240 Speaker 1: needed updates is much more expensive in the long arm. Now, 56 00:03:09,440 --> 00:03:12,920 Speaker 1: Senior writer Jonathan Strickland tells the story of another potential 57 00:03:13,000 --> 00:03:17,440 Speaker 1: solution to lead contaminating our water. Supply tiny, elegant microbots 58 00:03:17,480 --> 00:03:21,160 Speaker 1: that are reusable and can scrub of the heavy metal 59 00:03:21,200 --> 00:03:27,000 Speaker 1: out of water in just an hour. One of the 60 00:03:27,040 --> 00:03:31,480 Speaker 1: more challenging aspects of industrialization is dealing with waste. That 61 00:03:31,560 --> 00:03:35,560 Speaker 1: waste can include some pretty dangerous stuff, including heavy metals 62 00:03:35,600 --> 00:03:39,280 Speaker 1: like lead, mercury, and arsenic. Some scientists in Europe are 63 00:03:39,320 --> 00:03:42,400 Speaker 1: proposing a new way to remove these toxins from wastewater 64 00:03:43,160 --> 00:03:48,280 Speaker 1: tiny robots. These robots are incredibly simple in design. Imagine 65 00:03:48,320 --> 00:03:51,120 Speaker 1: a tube of material that has three layers. The outer 66 00:03:51,240 --> 00:03:56,680 Speaker 1: layer is graphine oxide, which adds orbs lead. Yes, add sorbs. 67 00:03:56,720 --> 00:03:59,320 Speaker 1: That means it holds particles of the metal against the 68 00:03:59,360 --> 00:04:02,320 Speaker 1: surface of a microbot, the way that sand holds onto 69 00:04:02,320 --> 00:04:06,480 Speaker 1: molecules of water. The microbots middle layer is nickel, making 70 00:04:06,480 --> 00:04:09,960 Speaker 1: the tube ferromagnetic. This allows a human to control the 71 00:04:10,040 --> 00:04:13,840 Speaker 1: movement of the microbots by applying an external magnetic field. 72 00:04:13,960 --> 00:04:16,920 Speaker 1: The inner layer is platinum. The purpose of this layer 73 00:04:17,040 --> 00:04:19,880 Speaker 1: is to provide the microbots with propulsion. First, you add 74 00:04:19,960 --> 00:04:23,440 Speaker 1: hydrogen peroxide to the wastewater. The platinum reacts with the 75 00:04:23,480 --> 00:04:27,320 Speaker 1: hydrogen peroxide, causing it to break down into water and oxygen. 76 00:04:27,360 --> 00:04:30,800 Speaker 1: The oxygen forms into bubbles which escaped the microbot tube 77 00:04:30,800 --> 00:04:33,880 Speaker 1: through the back. It's like a tiny little jet engine. 78 00:04:33,960 --> 00:04:37,640 Speaker 1: According to the scientists, releasing a sufficient number of microbots 79 00:04:37,680 --> 00:04:42,599 Speaker 1: into wastewater removes of lead in just an hour. Once 80 00:04:42,640 --> 00:04:45,359 Speaker 1: the microbots have done their job, you'd use a magnetic 81 00:04:45,440 --> 00:04:47,840 Speaker 1: field to move them to a collection point and lift 82 00:04:47,880 --> 00:04:51,080 Speaker 1: them out one quick bath in a special acidic solution. 83 00:04:51,160 --> 00:04:53,880 Speaker 1: Later and the microbots are ready for another go. On 84 00:04:54,000 --> 00:04:56,880 Speaker 1: top of that, you can reclaim the lead ions from 85 00:04:56,880 --> 00:04:59,520 Speaker 1: the solution and reuse them, as well as for the 86 00:04:59,600 --> 00:05:02,960 Speaker 1: other vy metals in wastewater. The scientists hope to increase 87 00:05:03,000 --> 00:05:06,360 Speaker 1: the absorptive abilities of the microbots to soak those up 88 00:05:06,400 --> 00:05:09,280 Speaker 1: in the future. They also hope to improve the manufacturing 89 00:05:09,320 --> 00:05:12,400 Speaker 1: process to bring down the costs. This could help developing 90 00:05:12,440 --> 00:05:16,839 Speaker 1: countries process wastewater responsibly while still allowing them to manufacture 91 00:05:16,920 --> 00:05:20,080 Speaker 1: the technologies we demand, such as batteries. It will help 92 00:05:20,080 --> 00:05:23,160 Speaker 1: cut down on the environmental impact our consumption has on 93 00:05:23,200 --> 00:05:25,920 Speaker 1: other parts of the world. Maybe it could even help 94 00:05:26,000 --> 00:05:28,960 Speaker 1: us treat lead contamination and water supplies and head off 95 00:05:29,000 --> 00:05:40,320 Speaker 1: future emergencies. Finally, this week, senior writer Robert Lamb explores 96 00:05:40,360 --> 00:05:44,039 Speaker 1: research into whether young children can spot and untrustworthy offer. 97 00:05:44,560 --> 00:05:47,400 Speaker 1: The good news is they totally can. The bad news 98 00:05:47,480 --> 00:05:50,400 Speaker 1: is that their morals crumble if the offer is sweet enough. 99 00:05:54,960 --> 00:05:58,239 Speaker 1: Here's how the study went down. Yale psychologist Karen Wynn 100 00:05:58,520 --> 00:06:02,280 Speaker 1: inside grad student are To Sammy, introduced five and eight 101 00:06:02,320 --> 00:06:04,960 Speaker 1: year olds to two characters, a nice kid and a 102 00:06:05,000 --> 00:06:07,520 Speaker 1: mean kid. They both offered stickers, but while the nice 103 00:06:07,560 --> 00:06:10,599 Speaker 1: kid offered a single sticker, the mean kid offered between 104 00:06:10,640 --> 00:06:13,000 Speaker 1: two and sixteen of the things. Most of the children 105 00:06:13,000 --> 00:06:16,000 Speaker 1: in the study had no problem rejecting large numbers of 106 00:06:16,000 --> 00:06:18,880 Speaker 1: stickers from the mean kid, except when the offer hits 107 00:06:18,960 --> 00:06:23,400 Speaker 1: sixteen because sixteen stickers is sixteen stickers. Who cares if 108 00:06:23,400 --> 00:06:26,360 Speaker 1: there's an increased wedgie risk? Right? Fair enough, those are 109 00:06:26,360 --> 00:06:29,840 Speaker 1: elementary school kids. But what about babies? This is where 110 00:06:29,839 --> 00:06:33,240 Speaker 1: the study really lands. The researchers conducted a similar experiment 111 00:06:33,279 --> 00:06:36,000 Speaker 1: with twelve and thirteen month olds, only instead of a 112 00:06:36,120 --> 00:06:39,600 Speaker 1: nice kid, mean kid, they played nice puppet, mean puppet. 113 00:06:39,600 --> 00:06:42,680 Speaker 1: We're talking a real jerk here, slamming box lids on 114 00:06:42,720 --> 00:06:45,080 Speaker 1: another puppet who just wanted to fetch a cool toy 115 00:06:45,120 --> 00:06:47,600 Speaker 1: out of a box, as opposed to the nice puppet 116 00:06:47,600 --> 00:06:50,320 Speaker 1: who tried to help after this little Punch and Judy show, 117 00:06:50,320 --> 00:06:53,039 Speaker 1: the nice puppet offered the babies a single cracker, while 118 00:06:53,080 --> 00:06:55,960 Speaker 1: the mean puppet offered to eight percent. Of the babies 119 00:06:56,040 --> 00:06:58,960 Speaker 1: took the single cracker because clearly this Punch character is 120 00:06:59,040 --> 00:07:02,560 Speaker 1: not a cool customer. But when Punch offered eight crackers, 121 00:07:02,600 --> 00:07:05,680 Speaker 1: that's when the resolve crumbled, like the very crackers they 122 00:07:05,680 --> 00:07:08,159 Speaker 1: sought to gum and litter the backseat of Mom's car with. 123 00:07:08,400 --> 00:07:10,040 Speaker 1: So how are we supposed to feel about all of this? 124 00:07:10,480 --> 00:07:12,560 Speaker 1: I mean, on one hand, it drives home a core 125 00:07:12,640 --> 00:07:16,280 Speaker 1: fact about infant cognition. Our human larva come preloaded with 126 00:07:16,320 --> 00:07:19,000 Speaker 1: the software they need to figure out this crazy, corrupt, 127 00:07:19,160 --> 00:07:23,600 Speaker 1: and sometimes dangerous world that includes logarithmic thinking and theory 128 00:07:23,640 --> 00:07:26,760 Speaker 1: of mind, the ability to judge how another person or 129 00:07:26,880 --> 00:07:29,720 Speaker 1: puppet is thinking. But does it also mean that humans 130 00:07:29,720 --> 00:07:32,000 Speaker 1: are sellouts down to our very core, that we have 131 00:07:32,040 --> 00:07:35,920 Speaker 1: an innate weakness to stranger candy, Nigerian letter schemes, and 132 00:07:35,960 --> 00:07:39,560 Speaker 1: poison apples. Tassini chooses to focus on the positive takeaway 133 00:07:39,680 --> 00:07:41,920 Speaker 1: that even one year olds are willing to pay a 134 00:07:42,000 --> 00:07:46,120 Speaker 1: personal cost to avoid slime balls some regardless of the 135 00:07:46,120 --> 00:07:54,480 Speaker 1: cracker based fortune. That's all for this week. Thanks so 136 00:07:54,560 --> 00:07:57,000 Speaker 1: much for tuning in. Subscribe Now for more of the 137 00:07:57,120 --> 00:08:00,640 Speaker 1: latest and strangest science news and some us your ideas 138 00:08:00,640 --> 00:08:03,440 Speaker 1: for new stories, and any feedback word you know, puns 139 00:08:03,440 --> 00:08:06,080 Speaker 1: you might have shoot us an email at now podcast 140 00:08:06,120 --> 00:08:16,600 Speaker 1: at how stuff works dot com.