It saves lives, facilitates commerce and clears the way for those coming and going in the great, white north.

Road salt is basically an unprocessed version of table salt, and is used to lower the freezing point of water on the roadways, making it more difficult to freeze. Nationwide, we scatter an estimated 20 million tons of salt on U.S. roads annually — about 123 pounds for every American, according to Columbia University’s Earth Institute, and it all began in 1938, when the chemical compound was first used in New Hampshire.

Some of the nation’s largest salt mines are located in New York (including just up the road in Groveland, home of American Rock Salt), Ohio and Michigan.

While the results of using salt are undeniable for certain conditions, it does not work in all cases, causing road crews to spread sand for traction when it gets too cold for salt to penetrate ice.

According to the New York State Department of Transportation (DOT), the best time to treat roads with salt is before a storm.

“Salting the road before a storm forms a layer of brine on the pavement, greatly decreasing the formation of ice on the roadway. Pre-treating allows us to use less salt and also makes it easier to plow the snow off of the road safely since the snow is not frozen to the pavement. This treating is also done with liquid products such as calcium chloride,” said a statement on its website.

Salt, however, is known to have some costly health and environmental impacts.

NYSDOT studies have found that deicing salt directly harms plants in the root zone by affecting water balance of cells, causing dehydration and collapse of plant tissues. Soil fertility can also be impacted over time.

Similar studies compiled in DOT reports have found that salty runoff can have adverse effects on local waters. Fish like lake trout that are dependent on high oxygen concentrations and low water temperatures are at higher risk than most. The zooplankton and micro invertebrates that they eat are also sensitive, but only in high concentrations not normally found following standard use of road salt nearby.

More than just wildlife can potentially be harmed by the use of road salt.

According to the ASPCA’s Animal Poison Control Center, ingestion of road salt by eating salt directly, licking salty paws, and by drinking snow melt and runoff “can potentially produce effects such as drooling, vomiting, diarrhea, loss of appetite, volcalizing/crying, excessive thirst, depression, weakness, low blood pressure, disorientation, decreased muscle function and in severe cases, cardiac abnormalities, seizure, coma, and even death.”

Exposure of your pet’s paws to road salt can produce painful irritations, inflammation, and cracking of the feet pads that can be prone to infection and are slow to heal.

According to the New York State Department of Motor Vehicles (DMV), the addition of sand to road salt helps to keep salt on the roadway.

Drivers traveling those roadways also know that road salt can cause vehicle rust and corrosion, particularly targeting exhausts, mufflers, coil springs, subframes and brake systems. The DMV suggests waxing your vehicle before winter, avoiding puddles that can hold salt, not traveling behind plows deploying salt, having your vehicle pre-treated against corrosion, and washing your vehicle when it becomes salty.

However, road salt is credited with saving human lives on the road every winter.

A 2012 Marquette University Study, commissioned by a salt industry trade association — The Salt Institute, credited its use with reducing crashes by 88 percent, injuries by 85 percent and accident costs by 85 percent. It also stated that application of deicing “pays for itself within 25 minutes after salt is spread.”

Taking the results of examining the costs and benefit of deicing with salt with a grain of salt, it seems that state and municipal governments will be sticking with the time tested chemical compound to solve the problem of icy roads for the foreseeable future.