Every year millions of tons of road salt is used to de-ice our roads. Sodium chloride (road salt) is toxic to animals and vegetation.  What happens to all that salt when it melts?  It makes its way back into the environment and our water.

One study by the National Academy of Sciences showed that salt concentrations in the fresh water is on the rise in states like Maryland, New Hampshire and New York.  In 2008, New Hampshire listed 19 water bodies damaged by chloride.  By 2010 that number had increased to 40.  With so many states getting deluged with snow these past few years, other states are likely to start showing higher concentrations in their fresh water too.

A study from the University of Minnesota found salt levels on the rise in 39 lakes in the Midwest.

Environmental Impact

Sodium chloride contains impurities and components like ferrocyanide, an anti-caking agent, that are harmful to vegetation and wildlife. Contaminants from road salt enter water resources by infiltration to groundwater, runoff to surface water and storm drains.  Road salt is completely soluble and is very mobile. Because there are no natural removal methods, dilution is the only partial solution

Birds often mistake road salt for food.  Salt is toxic for birds and even small amounts can cause death.

Many animals drink melting snow to relieve thirst. This can cause salt toxicity to wildlife like deer and moose.  They can become weak, confused and dehydrated.

Chloride also has a negative impact on aquatic life. It is toxic to many forms of aquatic life including fish and insects.

Salt causes vegetation to become dehydrated which leads to foliage damage and can harm root growth. It can also lead to nutrient disruption in the soil, causing plant death.

Human Health

Though chloride is not toxic to human health at low levels, excessive amounts in the water can definitely have negative impacts.  People with hypertension (high blood pressure) need to avoid high levels of salt.

Pets and Road Salt

Pets in areas with heavy salting are particularly vulnerable to chloride toxicity.  Licking paws and drinking snow melt can cause severe physical problems including vomiting, diarrhea, loss of appetite, weakness, disorientation, depression, low blood pressure and decreased muscle function. Severe symptoms can include cardiac problems, even death.  Exposure of road salt to pet’s paws can cause painful irritations and inflammation.

Do your very best to avoid roads with salt when walking your dog.  Wash off your pet’s paws after they have been outside.    Always make sure your pet has lots of good quality drinking water so they won’t be tempted to drink melting snow.

To your Health!

Peter Gillham