The modern obsession with disinfectants

Amid the Coronavirus scramble that has left my local Costco completely bare of hand soap, sanitizing wipes, and tissues, I had the completely irrelevant thought this morning that I haven’t washed my hair in weeks. I’ve done plenty to care for my hair – cowash, conditioner, combing, rinsing – but I haven’t used shampoo in an effort to bring my deflating curls back to life. This may sound gross or weird initially, but as the many curl support groups are fond of explaining, I’m just allowing my natural oils to coat my hair again, while only removing dirt and buildup. As disconnected as these two phenomena are, they have a common cause: since the early 20th century, we have been obsessed with disinfectants.


I blame the advent of germ theory. In the second half of the 19th century, an intense study of infectious disease spurred the rapid growth of knowledge about exactly what diseases are and how they spread. Culminating in the work of Robert Koch, scientists moved away from the Early Modern concept of spontaneous generation and instead began to see diseases as living organisms. Compounded by the intensification of public health concerns during the nineteenth century (caused equally by disease events and changing governmental attitudes), Western society began its effort in the 20th century to create cleanliness.

This effort toward cleanliness does not mean that Western society before the 20th century was dirty. In fact, our idea that pre-modern peoples were dirty is an attitude that comes from this period of change because this cleaning fervor made everything else seem filthy. Limited access to running water during the pre-modern period (via streams, springs, and occasionally plumbing) meant that washing oneself and one’s clothes could not be a daily occurrence. Kathleen Brown has written that pre-modern peoples instead developed a method of clothing that relied on a long white undergarment that covered the whole body and therefore would easily show dirt, both to protect the body from the dirt of the outside world and to protect clothing from the dirty excretions (sweat) of the body. This white garment could be cleaned easily and regularly by boiling or soaking in a harsh solution such as lye. The result is that premodern peoples likely had some persistent body odor, as well as stained exterior clothing, but were otherwise not covered in dirt and wore fresh garments next to their skin. (Consider also that modern clothing has a significant amount of plastic in it, which pools moisture on our skin and causes dirt and smells to collect, so our modern perspective of what it means to be dirty by the end of a day is colored by the behavior of our clothing.) Likewise, premodern food practices were very concerned with cleanliness – consider dietary laws that restrict the preparations of food and designate some foods as unclean, such as kashrut in Judaism, but also in traditions throughout Asia such as Buddhism. There is a persistent rumor that pre-modern peoples drank a lot of alcohol because their water was unclean. But this is contrary to pre-modern approaches to diet. People typically drank water directly from the source, such as a well or a spring, and without industrial pollution or poor hygiene practices such as graveyards near the water table, these water sources were as pure as they could be – not to mention, if you’ve ever made beer at home, you know that you can’t make it with dirty water, since the alcohol content of the beer isn’t high enough to purify the water and you would get sick from drinking it anyway. [Further side note: most stronger spirits are the product of the Early Modern period, i.e. exactly during this era of intense cleanliness, because they were easier to ship and store and therefore worked better as imperial products. So premodern peoples mostly didn’t even have access to the kind of liquors that could be safely consumed without proper storage, and once Early Modern peoples did, they wouldn’t have drunk them instead of water because they are dehydrating.]

This is a horrendous video, but the first quote pretty neatly summarizes modernity.

But the ideology of modernization had to view these pre-modern practices as uncivilized in order to distance itself from them. Modernity was a concept that was meant to position the empires of the West as the only islands of safety and stability in a sea of dangers across both time and space. In this imaginary, rural peoples within the empire, civilizations outside of it, and civilizations that came before it were all threats to its security. This ideology prompted the development of many public initiatives designed to control the impact of these outside actors, from municipal fire and police services to colonial interventions. In the public health sphere, Joseph Lister developed the concept of sterile surgery and the modern disinfectant. Now, I was once teaching a class with a professor who insisted that the medieval period extended right up to the day that Joseph Lister discovered the cleansing power of carbonic acid, because it freed people from the scourge of disease. This is both very wrong and very indicative of the modern obsession with disinfection. Just because we can control the bacteria in an environment in the short term doesn’t mean we are free of disease and infection.

Consider the major disease events that happened (in Europe and the US) after Joseph Lister: the massive spread of sexually transmitted diseases, especially HIV/AIDS; the seasonal flu as well as major epidemics such as the pandemic of 1889-90 and the Spanish Flu; the endemic West Nile Virus; Polio; cancer of all types; and of course any number of developmental and mental health conditions. So while Koch and Lister’s innovations were certainly based on correct facts, their perspectives, and thus their conclusions, were skewed. In the century since the West has sunk its teeth into disinfection, we’ve gained tremendous advantages from it – an expansion of safe surgery practices, greater insight into diseases and thus more cures and treatments, and a more broadly applicable standard of hygiene. But we’ve also learned that disinfection can have a negative impact. The last decade in microbiology could perhaps be defined by a growing awareness of “helpful” bacteria. The phrase “gut health” has entered our everyday language about ourselves and our diets. We’ve performed fecal transplants. We’ve also learned that some diseases can actually come from a lack of exposure to bacteria, as is the theory for the widespread incidence of peanut allergies. This isn’t to say we should swing the pendulum far the other way – in certain qantities and cases, disinfectants are good. Vaccines are good. But we have to understand when those cases are.

It’s this lack of understanding that leads to the strange situation we’re in, where people are rushing out to buy Purell and face masks. In the case of face masks, the public consciousness has completely lost the logic for why they’re useful, we simply associate them with the extreme cleanliness of an operating room (or, incorrectly, protection against much bigger particles like wood debris). When, in fact, surgical masks are used to prevent the doctor from infecting the open wound – and, very secondarily, to prevent fluids like blood from getting in their mouth and nose – not to prevent the doctor themselves from being infected. But in the case of Purell, we know why we use it, we’re just wrong about when to use it. We’re convinced that the spaces around us can never be too clean. And while a cleaner environment probably won’t help us catch COVID-19 any more easily, feeding our obsession for disinfection spreads panic. Moreover, if we think about the long term of the disease, it’s more beneficial for the human population as a whole to have a mild case of the disease than not to have it at all, because it encourages the development of a milder strain of the microbe and makes the disease easier to manage. There are some people who should absolutely be avoiding getting sick as much as possible, and for them, disinfection is appropriate. But for most of us, it’s a waste of energy and resources at best, and the source of long-term problems at worst. So let’s cool it on the disinfectant, and remember that there’s a time and place for everything.