Scientists have revealed the dangers of melting snow
Snow accumulated over the winter and actively melting in the spring carries a lot of dangers for humans, animals and nature in general. Scientists from Perm Polytechnic told us what harmful substances snow accumulates by the end of winter and who is particularly exposed to them, how these contaminants are dangerous for animals and plants, what measures to take to protect against them and how reagents can help in this situation.
When the snow cover is sampled for analysis, such an indicator as the content of substances per liter is considered. For example, in early December, "young" snow contains a small proportion of pollutants - from 0.2 grams to 1-2 grams per liter. By the end of winter, this indicator increases manifold. Snowflakes, falling to the ground, collect harmful particles from the air, and their share increases to 30 grams. And the snow that accumulates on the roadsides contains up to 100 grams of pollution per liter.
What substances does snow take from the air?
If there are chemical industry, heavy metallurgy and oil refining enterprises near the city, pollutants will enter the atmosphere one way or another. For example, in 2022, about 36,000 tons were emitted into the air from such enterprises in Perm, and 17.2 million tons in Russia. A significant part of these pollutants mixed with snow, among the components can be found ammonia, formaldehyde, hydrogen sulfide, hydrogen chloride and fluoride, phenols. In addition, nitrogen dioxide, soot and suspended solids (dust, ash and other combustion products) are released into the air from CHP plants.
How does melting snow affect humans and animals?
Universal prevention: after being outdoors, wash your hands and face immediately. In order for harmful particles to penetrate less into the house during ventilation, doctors recommend every three or four days to wipe the window sill and wash curtains more often - once every two weeks.
Children and pets can ingest snow while walking. Poisoning by pollutants in this case is unlikely: no one will eat very dirty snow, and freshly fallen snow contains a small proportion of harmful particles. The real danger is posed by various microorganisms, including pathogenic E. coli and fungi, which can live on snow.
Can reagents be good for nature?
The main task of de-icing agents is to lower the melting point of snow. For such purposes, chemical preparations based on sodium chloride, calcium and magnesium, sodium acetate and formate, potassium, calcium and ammonium are suitable.
The most innocuous and even useful chemicals are formates. First, sodium formate in the composition of de-icing agent almost six times reduces its destructive effect on metals and concrete. Secondly, sodium and potassium formates are biodegradable at low temperatures, and therefore do not accumulate in the form of harmful substances in the soil.
How is dirty snow dangerous for rivers and plants?
Snow acts as a sorbent for pollutants in the air. In spring, when it begins to melt, harmful particles are spread everywhere: they end up in the water and air, on roads and house walls, on people's skin and pets' fur. Washing, damp cleaning and washing curtains in good time can help protect you from negative effects.