Guest post: A plunge into the artificial sweat industry

Some time ago I purchased a tiny bottle of synthetic sweat from a reputable chemical company for $141. The bottle of “Artificial Eccrine Perspiration – Stabilized” contained a teaspoon (5ml) of a fluid that mimics something many of us produce in vast quantities to cool down, or at least I do. During a recent 45-minute spin class, I collected nine teaspoons of my own sweat by catching it in a mason jar as it poured down my skin.

In fact, if you put all humans on Earth in an enormous sauna so that we began to sweat collectively, we would all produce a flood of perspiration on par with Niagara Falls on a hot summer’s day – a bemused employee at the Niagara Parks Commission helped me figure this out based on average human sweat rates from our 2-5 million sweat pores.

This raises an important question: why would anyone need to buy artificial sweat? Moreover, should I start a side business selling my own sweat, given that I could make $1,260 every spin class?
The synthetic sweat company, Pickering Labs, where I bought my teaspoon sample of sweat, sells more than 50 different kinds of synthetic sweat products. When I asked Pickering Labs about the size of its synthetic sweat sales, back when I was writing the book The Joy Of Sweat, the company’s director of operations, Rebecca Smith, demurred. However, she did note that “it is safe to say we sell hundreds of gallons of artificial perspiration each year.” In fact, compared to synthetic mimics of other bodily fluids, such as saliva, urine, or earwax, Smith said “artificial perspiration is our largest selling product category.”

Despite humanity’s homemade supply, bottles of artificial sweat circulate the globe to satisfy the demands of an artificial perspiration market. Multiple industries — forensic, handheld electronics, textile, jewelry, music — rely on a steady supply of pseudo-sweat to comply with government regulations or to ensure their products’ quality does not plummet from the sweat dripping off overheated humans.

Clothing manufacturers, for example, buy sweat mimics because they need to ensure that textile dyes do not leach out when people perspire in their products, or that colors do not change or fade in high-sweat areas like the armpit. Companies that manufacture personal handheld electronics need to ensure their phones and tablets are responsive to sweaty fingers.

Meanwhile, producers of earrings, watches, and clothing zippers — any metal objects that touch the skin — should check that sweat does not cause significant amounts of nickel to leach out from the jewelry. On some skin, leached nickel can cause a rash called contact dermatitis.

One of my favorite applications for synthetic sweat is in the world of music. No guitarist, for example, wants the sound quality of their raucous solo altered by the corroding power of salty sweat. Case in point: when I wandered into my local guitar store to talk sweat, the metal guitarist behind the counter told me he is such a sweaty human that he needs to change his electrical guitar strings after just three performances to maintain sound quality.

Clearly he is not the only guitarist with this perspiration conundrum. Some companies even sell high-end guitar strings that claim to repel sweat.

Because I am a recovering scientist and a weirdo, I hatched a plan to use my caches of sweat – both synthetic and my own – to see how perspiration affects the sound quality of guitar strings.

I am fortunate to have a sound-engineer buddy, Dean, who agreed to give this Gonzo experiment a scintilla of scientific credibility.

Dean would string up a guitar with normal and fancy anti-sweat strings, and we would see how the sound quality was impacted after a 24-hour soak in the two perspiration samples. I was curious to see whether artificial sweat was as good (or perhaps better?) at affecting sound quality as my own homemade perspiration. I was also curious about whether fancy, sweat-repelling guitar strings could protect sound quality better than the plebian versions.

Fueled on bagel sandwiches and a carafe of black coffee, Dean changed strings on his guitar, then plucked a variety of notes while taking spectrograms to assess how the different sweaty soaks messed with sound quality.

Compared to the unsoaked controls, all the strings soaked in sweat lost what Dean called “sustain,” which is how long a sound lasts after a string is plucked. However, he found that the anti-sweat strings were not as affected by sweat as the common, cheaper versions.

The same held true for the “brightness” of the sound, that is, the presence of higher frequency components of a note (the treble) when a string is plucked. Strings with no perspirant protection produced duller sound after a sweat soak, especially higher note strings E and A; however, the sound brightness of fancy anti-sweat strings was barely affected by being soaked in sweat.

Both my sweat and the synthetic stuff had similar impact on guitar-string sound quality, though this varied a bit too, string to string. We found that my sweat was particularly corrosive to the basic, not expensive G-string — a detail that led to many adolescent witticisms as we became punchy in the sound studio.

Of course, this “experiment” was a barely legitimate first try. We did only one long day of testing. To pass peer-review, we would need dozens of repeat sessions, ideally on multiple brands. Yet it was fun to see that – at first brush (or dare I say pluck?) – a company’s claims about anti-sweat protection did hold up to our rudimentary tests, and that synthetic sweat approached the corrosive potency of my own.

As for the siren call of starting a homemade sweat shop on Etsy: I have made the difficult decision not to sell my perspiration online. But I will still smirk to myself every time I produce puddles during a workout and reflect on the lost currency of the liquid.