How Safe Is it Safe to Eat Snow?
‘As white as snow’ is a very popular simile, and the pure white colour of snow is usually taken to mean that it’s pure,clean and pristine. Based on this fact, when it snows, many people would not be afraid to scoop a handful of snow off the ground and into their mouths.
While swallowing up this snow, have you considered how clean it is? Fengjing Liu, a hydrologist and biogeochemist at Michigan Tech, quoted on Getpocket, says it is at least cleaner than rain, “During the formation of ice crystals, few impurities fit into the crystal,” he says, adding that the process of water being supercooled by low temperatures can almost act as a filtration system, pushing impurities out.
However, is snow still so clean after it has fallen to the earth? “In some studies, snow appears to maybe even be a better collector of heavy metals and other pollutants in the atmosphere than rainfall, because it has a larger surface area and slower velocity,” explains Jordy Hendrikx, director of the Snow and Avalanche Laboratory at Montana State University.
The two experts, Liu and Hendrikx agree that it could be safe to eat fresh snow in small quantities with Hendrikx adding that he lets his kids eat a little snow while skiing in the Rockies. He advised, however, that people should avoid eating snow that has sat on the ground for too long. “I do want to emphasize that for snow staying on the ground for some time—usually called snowpack—its chemical concentrations will increase significantly because of accepting the dry deposition,” says Liu. Dry deposition means that dry particles of dust and pollution in the air will settle in the snow over time. The longer it sits, the more the chemicals accumulate. Week-old snow isn’t a great snack.
He also says to pick your location smartly when planning to eat snow, as snow in urban regions would be a lot more polluted than that of rural areas.Nevertheless, this is not to say that the snow in the rural areas is 100% pure either. “The thing you do need to think about is: the air masses that are moving around [bringing in weather and snow] are coming from a long way away,” says Hendrikx.
Hendrikx says it is a myth that snow at high altitudes is unspoiled because researchers have gone up to Everest, measured concentrations of heavy metals and found that those concentrations weren’t necessarily lower at higher elevations,“There was a study on Everest that started at Base Camp, and the researchers went up to 7,800 meters, taking snow samples every few hundred meters,” says Hendrikx.
While it may or may not be safe to eat snow, Liu warns that it is definitely unsafe to drink fresh snowmelt runoff. According to Liu, as snow begins to melt, it goes through a natural phenomenon in which itquickly sheds the chemicals mixed into the snow. This renders the first snowmelt a lot more concentrated in harmful chemicals than you’ll get in a handful of snow.
How about coloured snow, you may ask? Liu warns that this is also a firm no. Yellow snow gets that way when it is mixed with pee, “Snow could have colour if it is contaminated by bacteria,” he warns.