Soil Pollution: The Health Risk No One Is Talking About

You know about climate change and its hazards, but did you know that the earth beneath your feet could be toxic?

Soil plays a role in every aspect of life: food, water, air, and health. The Food and Agriculture Organization (FAO) of the United Nations estimates that 95 percent of our food is directly or indirectly produced on our soil. That makes soil pollution an alarmingly real and significant health risk. “Although soil pollution is not as easily perceived as plastics in the oceans, it frequently has long-term impacts on human health and the environment,” says Ronald Vargas, a soil scientist and Secretary of the Global Soil Partnership for the FAO.

In fact, soil pollution may be contributing to a mass extinction—the sixth scientists have been able to record in the planet’s history. The bad news is that all the previous ones included global topsoil disturbances. The United Nations estimates up to “90 percent of the planet’s species have disappeared, and 40 percent of biologic life. We are losing a species to extinction at a rate of one every 10 minutes.” If that raises your heart rate, you could have eco-anxiety.

The soil crisis is hitting humans just as hard as it hits animals: “Eating contaminated food once may have no impact if the contamination level is below the risk values, but contaminants accumulate in organisms’ tissues, which is called bioaccumulation,” says Vargas. “As we go up the food chain, contamination levels increase and this is called biomagnification.” And guess who is sitting atop that food chain taking the full blast of bioaccumulation? Humankind.

To be clear, soil is not the same thing as dirt. Soil teems with living organisms—it’s like a thin layer of skin that covers our landmasses. Dirt, on the other hand, is soil that is depleted and severed from the ecosystem—it’s inert or dead.

Is soil a renewable resource?

Two hands of the men was carrying a bag of potting seedlings to be planted into the soil.kram9/Shutterstock

“Soil is a finite resource, meaning its loss and degradation is not recoverable within a human lifespan. The current rate of soil degradation threatens the capacity of future generations to meet their most basic needs,” reports the FAO of the United Nations. We’re losing the equivalent of a soccer field’s worth of soil every five seconds, according to the group’s experts. But as dire as that sounds, experts say the soil can still be revitalized—if we make it a priority.

What kinds of things degrade the soil?

spray plants crops garden pesticidesTuttoo/Shutterstock

Flooding and high winds can lead to soil erosion, but if we want to point fingers we’d better take a look in the mirror: Human activities are the primary cause of soil pollution, according to the FAO. Agricultural practices that rely on herbicides and pesticides and excessive tilling can damage the soil structure and kill off the soil’s beneficial bacteria. Urbanization strips the soil’s vegetation cover, compacts soil during construction, interferes with drainage, and can cause surface run-off. Sewage, overgrazing, and deforestation also pose enormous threats to the soil.

How does soil get polluted

Modern coal mine Passageway in modern coal mine with tracksPrzemek Tokar/Shutterstock
Mining destroys crop cover and disperses toxic chemicals that poison soil; certain types of manufacturing release of toxic emissions and waste into the atmosphere or rivers and oceans; eventually, the toxins settle into the soil. Even though lead gas was banned in 1996, lead is still one of the most common soil contaminants, says Ganga Hettiarachchi, PhD, a professor of Soil and Environmental Chemistry at Kansas State University in Kansas. The aggressive chemicals some farms employ can reduce the amount of organic material in the soil, slowly robbing it of fertility. And there’s a new category of pollutants steadily building up in soil thanks to pharmaceuticals and personal care products that seep into our soils from groundwater and landfill.

How do soil pollutants transfer to people?

The most common ways we absorb soil pollution are working with it, inhaling it, or eating it, explain experts at the FAO. You inhale airborne soil particulates. And a particularly troublesome exposure is eating it—you get tiny bits in your food, for example. Small children, who are less discriminating about what goes into their mouths are particularly at risk for ingestion. But older kids and adults can also accidentally eat toxic soil from, say, unwashed produce.

How does soil pollution impact your health?

Soil is supposed to be our first line of defense against contaminants: It can do a great job of filtering out toxins. The issue is that we’re overloading soil’s ability to act as a buffer. “If soil’s capacity to protect us is exceeded, contaminants will (and do) seep into other parts of the environment—like our food chain,” reports the FAO. Ultimately, soil pollution affects food security by reducing crop yields and quality, meaning insects, birds, mammals—including humans—will have fewer and fewer safe and healthy food sources.

Soil contaminated with dangerous elements such as lead or plastics, or pharmaceuticals such as endocrine disruptors, can raise the risk of chronic disease such as heart problems and cancer. The CDC declared in 2012 that lead can be harmful for children in any amount.

Antibiotics can seep into the soil to help fuel the creation of drug-resistant bacteria. According to a report by the World Economic Forum, each year around 700,000 deaths are attributable to antibiotic-resistant bacteria, a number that experts expect to climb.

What’s the best way to limit exposure to toxic soil?

Take basic precautions like keeping your house free of dust and washing your hands after working in the garden or yard. Thoroughly wash your produce before preparing it. Keep a careful eye on young children—they love putting dirty fingers (or just dirt) into their mouths.

If you’re concerned about lead in the soil around your home, you can have it tested, says Hettiarachchi. She recommends making use of your state’s university extension program to learn more about local contaminants; they can also do soil testing. To manage soil contamination and erosion, you can add compost to your yard to dilute any toxins and increase microbial activity. You can limit soil erosion by planting native species, advises the FAO.

How can we reverse the damage?

“Our daily choices have a big impact on soil pollution; if we choose to recycle, reduce and reuse items instead of buying new products every time, we will reduce the amount of waste that ends up in illegal and legal landfills, which is one of the main sources of soil pollution,” says Vargas. “As a society, we can also pressure our local and regional governments to advocate stricter control of industrial activities and their emissions and wastes.”

You can also look to support organizations and industries that prioritize sustainable, non-toxic growing and manufacturing practices will also help. Some groups that may be of help include the FAO, of course, but also Kiss the Ground, Non-Toxic Neighborhoods, and Farmer’s Footprint.

“To reduce the collapse of human health, we need to take care of our soil again,” says Zach Bush, MD, of Farmer’s Footprint. For all of us, awareness of the importance of our soil begins with knowing what is happening right beneath our feet.

Medically reviewed by Oscar H. Cingolani, MD, on November 23, 2019

Elizabeth Marglin
Elizabeth is a Colorado-based journalist specializing in spirituality, sustainability, health and wellness. Her work has appeared on Reader’s Digest online, in Yoga Journal, Prevention, AARP, Backpacker, 5280 and in dozens of others publications. Elizabeth loves that her job requires non-stop learning. Her curiosity about the world is insatiable—and she has a knack for distilling complex concepts into understandable talking points.