Heavy Stuff

It’s peculiar that we know that lead is poison, that there is no “safe” amount to put in your body, and yet we still put it in our bodies. It is peculiar because you would think that what we know would inform what we do; you would think, for example, that Flint, Michigan, would not choose to use a river that had been poisoned for nearly a century as its municipal water supply. The fact that it did—the impossible-to-avoid fact that this is the choice that was made in Flint, Michigan—forces us to re-evaluate the basis of that expectation. One of the terms is wrong. Is it “we”? Is it “know”? Is it “safe”?  Is it “choose”?

Or maybe it’s the word “peculiar,” which has two primary but opposed meanings: “strange” and “particular.” Describing slavery as America’s “peculiar institution” in the 19th century, for example, was not meant to imply that slavery was strange, but that it was particular to the southern United States (the rest of the world having mostly abolished it). In this sense, it was anything but “estranged” or “alien”; precisely in its particularity, “the peculiar domestick institution of the Southern States,” as John Calhoun put it, was what made his home what it was.

If it’s peculiar that we drink poison, as a society, then there are one of two choices: either it’s a strange and inexplicable practice, or it’s what makes us who we are. It might also, like the word peculiar itself, be a strange and particular combination of both.

Here is what we know. We know that if you run water through lead pipes, some of the lead will dissolve in the water, especially if you let the water sit in those pipes, or if the water is corrosive. Soft water, warm water, and water that’s high in calcium carbonate will tend to corrode the lead from pipes, though treating a supply with orthophosphates—as the water from the Flint River was not—will cause a protective layer to form on the inside of the pipes, preventing the lead from leaching into the water. But it is not a good idea for a public utility, the entities entrusted with the maintenance of social infrastructures, to put lead in the water. The reason is that if you drink lead-contaminated water, the lead will enter your body and interfere in basic physiological processes. It will do this, primarily, because your body doesn’t know what lead is, and will mistake it for things it can use, especially calcium. This mis-recognition will impair brain functions; it will shorten the life expectancy of existing blood cells and impede the production of new blood; it will kill neurons and damage kidneys; it will destroy fertility; it will alter the body’s prooxidant/antioxidant ratio, disrupting the immune system; and it will alter the metabolism of essential fatty acids. It will interfere with magnesium-dependent processes.

“Poison” is a word for all of this, the kind of simple word that children must learn at an early age if they are to survive. We are susceptible to lead poisoning, as a species, because “our internal biochemistry reflects the composition of the uncontaminated primeval biosphere,” as David Purves puts it; our chemical metabolism depends on the presence of essential trace elements like cobalt, copper, manganese, and zinc. But it also depends on the absence of antimony, arsenic, beryllium, cadmium, lead, mercury, and thalium.

Our bodies don’t know what lead is, and so they mistake it for other things, things they can use. Utility is confusing in this way.

Numbers can offer a tempting clarity. A study published in March, for example, focused on long-term studies of low-level lead exposure and cardiovascular disease, and declared that “nearly 412,000 deaths every year in the US can be attributed to lead contamination,” a number that’s an order of magnitude greater than what would have previously been “known.” It’s an upsettingly large number, close to one in every seven deaths. Of course, the phrase “can be attributed” is the price we pay for such a clean number; there’s an inverse relationship between how precisely we quantify the damage being done and how certainly we can know that lead is the cause: the more precise the number of deaths, the less precisely we can say that lead was more than a contributing cause. Of course, the less precise we are about the damage, the more certainly we can know that putting lead in your body is, on balance, a bad idea.

On balance, it’s a bad idea to put lead in your body. The really peculiar thing is that we’ve known this for a long time, for as long as “we” have “known” that lead could be used to deliver drinking water at all. It was the Romans who came up with the idea of using lead for plumbing—naming plumbing after their word for lead, “plumbum,” or liquid silver—but it was also the Romans who first discovered that there were good reasons not to drink from lead vessels. Observe the pallid color of lead workers and see how the “vigor of their blood” was destroyed by the fumes from casting lead, Marcus Vitruvius Pollio commanded. In his foundational work of classical architecture, De Architectura, the only architecture manual to survive from antiquity—in which he derived architectural aesthetics from a consideration of the human body, leading to one of Leonardo Da Vinci’s most famous paintings to be called “The Vitruvian body”—Vitrivius argued that there was a relationship between how to build cities and houses and how to build bodies, and it therefore followed that we should keep lead out of both bodies. “Water should therefore on no account be conducted in leaden pipes,” he writes, “if we are desirous that it should be wholesome.”

Are we? This is the question that lead makes us ask. Since water has been and still is conducted in leaden pipes, perhaps we are not desirous that the water be wholesome. We drink much less lead than we used to, but if we measure lead poisoning in our environment the same way we do with living creatures—“the same standards to the inanimate as to the quick,” as Christian Warren puts it, “by the quantity of the metal present in the body—ions of lead in tissues, blood, and bone—rather than by any symptoms”—then the United States is, simply, lead poisoned. “The lead in the nation’s buildings, its water pipes, the dust and dirt along its highways, and the air of its cities certainly constitutes a major absorption.”

Another point of lexical clarification: “plumbism” is the technical term for lead poisoning; “plumbing” is an infrastructure, and a “plumber” is a person who installs and repairs it.

Why would we use lead pipes to transport water? Why not… not use the lead for that? Why not leave the lead as un-smelted lead sulfide, the much more insoluble crystalline form that we tend to find it in when we find it in the ground as the ore called “galena” (PbS), or in its oxidized version, anglesite (PbSO4) with black crystals turned white and grey? Or in the bright green ore pyromorphite, (Pb5(PO4)3Cl), or in the mimetite (Pb5(AsO4)3Cl), which mimics pyromorphite in soft yellow and orange crystals? Or vanadinite (Pb5(VO4)3Cl) with its reds and browns?

Lead doesn’t just happen. The EPA website observes that “Lead is a naturally occurring element found in small amounts in the earth’s crust,” and that “Lead can be found in all parts of our environment – the air, the soil, the water, and even inside our homes.” But this sort of claim—which one finds not only in literature from the Trump-era EPA—aggressively blurs the distinction between what we found and what we made. There’s a key difference between smelted, purified lead and a lead sulfide ore, between the naturally-occurring form that’s relatively safe to touch—but works really poorly as material from which to make pipes—and the form of lead that’s literally poison but is otherwise an excellent material to transport water into human bodies. We find lead sulfide in the soil; if we find much lead in the air, water, or “inside our homes,” it tends to be because someone dug up the lead sulfide, smelted the lead out of it, and then used that toxic lead to build a water-delivery system (or otherwise ran the water through it). You don’t want to eat or drink either form of lead, but you’re only really in danger from the second form.

Why not use—as Vitruvius suggests—earthenware vessels? Why not not put lead in our living environment?

We have trouble with “Why not not.” We have trouble knowing what we know. As Benjamin Franklin observed, in a 1786 letter, “The mischievous Effect from lead is at least above Sixty Years old”; in response to a friend’s query about “the bad effects of lead, taken internally,” he recalled his youthful experience with lead printing tools, and marvelled at how long it had been known that lead should not be taken internally. It made him reflect on the difficulty of knowledge becoming useful. “You will observe with Concern how long a useful truth may be known, and exist,” he said, “before it is generally received and practis’d on.”

In general, Franklin was of the opinion that the problem of “useful truths” was a lack of communication, of information left un-disseminated; it’s why, in 1743, he proposed a society to promote useful knowledge by building bridges between what the various members in various places could know. “[M]any Hints must from time to time arise, many Observations occur, which if well-examined, pursued and improved, might produce Discoveries to the Advantage of some or all,” he suggested; since most colonists in the Americas “are widely separated, and seldom can see and converse or be acquainted with each other…many useful Particulars remain uncommunicated, die with the Discoverers, and are lost to Mankind.”

Is this lack of an infrastructure the problem with lead? Have “hints” from time to time arisen that lead is poison, only to be lost, scattered, and un-disseminated? Perhaps. The classic symptoms of lead poisoning were established in the years just before our cities begin building public water-works out of lead, on a scale never before dreamed of; on some level, “we” should not only have known better, but we did. But could Franklin’s society have circulated all that “useful information” about lead without using lead printing tools?

The problem is that lead is useful. Lead is cheap, and yet durable when not under physical stress; it can be dense when that’s an advantage, and soft and easy to shape, with a low-melting point, when that’s an advantage. Most of all, lead is good at connecting. Pipes connect public utilities to domestic plumbing, lead solder welds circuits or any metal-to-metal connection together, and lead batteries conduct electricity through connection: lead is useful, above all, for creating circuits and connections. Even paint is a coating that contains and covers, but also connects.

It’s impossible to talk about lead without talking about connections; in practice, in industrial society, it’s just as hard to talk about infrastructural utility—or the question of who counts as “we”—without taking in a little bit of lead.

The simplest answer for why we’ve been drinking lead for so long is, of course, money. The Romans smelted silver to make coins and produced such a reliable layer of lead pollution in doing so that scientists can track the ups and downs of the Roman economy by testing lead levels in Arctic ice. By the same token, the lead industry has always made money because the work it could do with lead needed to be done, and needed to be done so much that it produced more than just use value; that surplus is used to produce advertising about lead, naming it “the useful metal” in books with titles like Useful Information about Lead.

“Everyone knows something about lead, but detailed information regarding its physical or chemical properties and application to industry is scattered throughout technical literature,” declares the opening passage of the Lead Industries Association’s 1931 Useful Information about Lead, echoing Benjamin Franklin’s understanding of the problem. “The purpose of this book is to supply those who use, or contemplate using lead, a comprehensive account of its characteristics.” Useful Information about Lead observes that plumbing is “the least noticeable part of a building…yet the most important to the health and comfort of the occupant.” It does not, however, contain the words “poison” or “toxic.”

The Romans used lead to drink with because it tasted good; they put lead acetate (“sugar of lead”) in a variety of dishes, as did their medieval successors, especially to counteract the taste of tannins. That practice, however, is long gone. Today, the problem is that lead plumbing keeps connecting, even long after you’ve stopped noticing; it “will almost invariably outlast the building it is called upon to serve,” as we learn on page 74 of Useful Information about Lead. Pipes made of galvanized steel can last 20 to 50 years; copper pipes last at least 50 years; and brass can give you 40 or 70 (yellow brass and red, respectively). Lead pipes, on the other hand, lasts so long that the Residential Inspection Guide that I used to get those figures doesn’t even bother to tell you how long it lasts: long before they’ll break, you’ll need to replace them because they’re poison.

But will we? We don’t make new water pipes out of lead; Section 1417 of the 1986 Safe Water Drinking Act defined “lead-free” for pipe and fittings as no more than 8% lead by weight, and in 2011, that was lowered to 0.25%. Since from that point on, all new pipes, fittings, fixtures, solders, and flux had to be lead-free by those standards, there has been much less lead in new pipes. But pipes from before that time, well, they remain. And if there is one thing that lead is really good at, it’s remaining.

This, then, is the problem. We don’t use it because we want it; we use it because we don’t want not-it enough. And so, the lead is still there: we’ll replace the lead pipes if they break—if they stop being useful—and when we replace them, we’ll replace them with copper or something “lead-free.” But while we’ve got all these lead pipes that haven’t yet been replaced, the useful thing about them is that we don’t yet have to replace them. It’s a variation on the “but we need the eggs” joke, where knowing what the problem is isn’t really the problem; you’ve always known what the problem is; the real problem is that you don’t really want the solution.

Liquid silver, utility, “the useful metal.” The problem is that lead pipes are more stable and long-lasting than the social consensus on their safety, outlasting the window in time in which people think that making lead pipes was a good idea. Lead will remain in the system even after it’s all gone, in fact: the most remarkable thing about lead might be the trace of its usefulness, even after we’ve switched to less harmful materials. We won’t get rid of it until it breaks, but when it breaks, we’ll need to replace it with something precisely as useful. In this way, lead isn’t just poisonous; it’s useful in a way that makes us try poisonously hard to do the things it did even after we don’t use it. Lead-free solder requires vast amounts of tin to be mined, rather than recycling old lead; the copper in copper pipes has to come from somewhere, and is dirty when it does. And what do we do with all the lead we’ve carefully removed from our pipes, our paint, and our batteries? Do we throw it away with all the other trash?

Lead doesn’t just leave tainted soil; it leaves a variety of social practices tainted by path-dependent techniques and expectations that we wouldn’t have built without the toxic convenience of lead to show the way. Like lead in Arctic ice, it’s a history inscribed in the permanence of the earth; lead is the ballast connecting us to the past, but also, lead is the thing that will remain.


Ingredients is a regular Popula column, in which we explore the things that go into other things in order to become the things that they are.