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When I first started climbing as a teen, I could never have too much chalk. My hands were naturally sweaty anyways (the first signs of what would eventually develop into a neurological autoimmune disease), and I thought chalk was the cure-all. I chalked up before a route, I chalked after clipping bolts, I even chalked up while belaying sometimes, just to get a better grip on the rope.
More than the added grip it gave me while climbing, I just liked the feeling of chalk on my hands. I even joked about wanting to carry a bag of chalk with me outside of climbing, so I could chalk up before I shook hands with adults or held hands with girls on dates (I was constantly nervous about my greasy hands).
When I was climbing I chalked up indiscriminately, whether indoors or outdoors. A spilled chalk bag was a goof, the chalky clouds floating in the air around my gym were a minor irritation, nothing more.
Now, most modern gyms are well-ventilated, high-ceilinged, and all-around much larger than the 15×15 plywood cave I grew up climbing in. However, regardless of where we climb, we all know the familiar chalky haze in the air, the white clouds that explode whenever someone with an overfilled chalk bag chalks up or takes a fall. Chalk overuse is especially common with newer climbers. One of the telltale signs of a gumby is the chalky aura hovering around them in the gym.
So using too much chalk is already thought of as slightly annoying or cringey, but what many people don’t realize is that there are legitimate health concerns, too. Chalk isn’t the totally benign substance we sometimes think it is, and overuse of chalk isn’t without its drawbacks, for us, those around us, and for the places we climb.
When you start to think about it, it’s not really surprising that “inhalation of magnesium carbonate [aka chalk] has been shown to cause respiratory system irritation, cough, and pulmonary problems” (we could all do with less ‘respiratory system irritation’ in 2021…right?).
However, what you might not realize is that you don’t have to take a bong rip-style inhale straight out of a chalk bag to get high levels of chalk into your lungs.
A 2019 study at Appalachian State University’s rock gym found particulate matter from chalk dust in the air was “consistently in the unhealthy to hazardous range” based on the Environmental Protection Agency’s air quality index. This study only analyzed ASU’s gym and another climbing gym at Old Dominion University (which was in the “good to moderate” range) but if one out of two random college climbing gyms in a study has air quality levels in the hazardous range, think of how many other gyms across the country do as well!
Meanwhile, an older German study found the particle mass (chalk) concentrations in indoor German climbing gyms “reach, in many cases, levels which are observed for industrial occupations.” While the dust concentrations in the study were still below German occupational exposure limits for respirable and inhalable dust, they “[exceeded] German guidelines for workplaces without the use of hazardous substances.” Yikes.
You might scoff and say, “Well I’ve never had any respiratory problems,” but what about ten years down the line?
Besides, even if you aren’t ever affected, many of our fellow climbers suffer from pre-existing respiratory disorders such as asthma, and for folks like that, constant exposure to these levels of particulate matter is really bad news.
It goes without saying that in addition to chalk’s potential health hazards when abused indoors, it also contributes to defacing the rocks we climb on outside. Many high traffic crags are starting to ban chalk, and as more climbers transition from gym to crag, chalk goes from health hazard to pollutant. Chalk stains both mar the rock face and degrade it over time, and on popular routes it can become a real problem. If you’re an indoor climber looking to transition to the crag outside, becoming accustomed to using less chalk is a great idea, and can help ensure you can go climb in many places that are starting to institute chalk bans without a significant reduction in your performance.
Don’t get me wrong. I’m the last person to call for everyone to stop using chalk (my hands are usually so sweaty it feels like I just dunked ‘em in a tub of buttery popcorn). But we could all do well to be a little more conscious of how and when we choose to chalk up.
Studies have shown that using liquid chalk and chalk balls in indoor gyms dramatically reduces particulate matter in the air, when compared to loose chalk. When climbing outside, there are a number of eco-friendly chalk substitutes that don’t mar the rock, from commercial products like the Metolius Eco-Ball to natural methods like taking dried leaves from the ground and crushing them between your hands (no comment on how well this technique works, though I have a friend who swears by it). If you are using traditional chalk, using a chalk brush to scrub away your tick marks and clean other grime off the holds post-climb is a great way to ensure the route stays clean for future climbers. There are a number of things gyms themselves can do, too. Studies also show that running ventilation systems dramatically reduces chalk buildup in the air, as does opening windows (duh, huh?). Ironically, many of the same measures we’ve all been taking to reduce coronavirus risk can help reduce chalk buildup in the air, too.
The bottom line is we all use chalk, and by and large, that’s not a bad thing. But as our gyms and crags become increasingly crowded, we should all learn to be a bit more conscious of the negative impact chalk overuse can have on those around us and the places we climb, and let that inform how we choose to chalk up. That chalk cloud may not bother you, but it could pose a health hazard for those around you. If you’ve used loose chalk all your life, maybe check out liquid chalk or a chalk ball as an alternative. If you’re heading outside, maybe try to send a couple of routes sans chalk now and then.
Owen Clarke is a writer currently based in Tennessee. He is a Contributing Digital Editor at Rock and Ice and Gym Climber. He enjoys Southern sandstone and fish tacos, and is afraid of heights.
Follow him on Instagram at @opops13.