What is Soil Pollution?

Soil is typically an ignored area of biodiversity, yet even a small piece may be teeming with life, ranging from minute creatures to fungi and earthworms, all of which play an important part in the soil ecosystem’s functioning. This is also where nutrients are converted into forms that plants can use, allowing the biomass to produce and store carbon. Our potential drinking water also initiates its natural purification journey towards the groundwater from the soil only.

Soil pollution is described as the presence of hazardous compounds (pollutants or contaminants) in such quantities in the soil to endanger human health and/or the environment. Even if the amounts of pollutants in soil are not high enough to constitute a concern, soil pollution is considered to occur if the levels of contaminants in soil exceed the levels that should naturally be present.

According to the Food and Agricultural Organization (FAO) of the United Nations, soil contamination is a global concern that is especially severe in regions such as Europe, Eurasia, Asia, and North Africa. According to the FAO, one-third of the world’s soil is already severely or moderately degraded. Furthermore, regeneration is so sluggish that creating a 1 cm layer of arable soil would take 1,000 years.

Soil contamination comes from a variety of sources, ranging from the primary sector through the last stages of the life cycle of common items. Here are a few examples:

1. Agricultural sources: artificial chemicals such as pesticides, herbicides, fungicides, and fertilizers
2. Industrial sources: Industrial wastes or by-products in the form of liquids, solids, or gases
3. Urban wastes: Food waste, plastics, industrial wastes, e-waste, and general household wastes
4. Other wastes: Sewage sludge, Mining activities, nuclear wastes

Soil Pollution Causes

Soil contamination is a difficult issue that must be addressed. We all must understand how vital soil is to us. The sooner we recognize the problem, the better we will be able to fix it. Because it is a complicated problem, everyone, from an individual to the government, must work together to solve it.

Soil Pollution is roughly grouped into two types:

• Soil Pollution induced by natural processes: Some contaminants naturally build in soils as a result of relatively unusual processes. This can happen in the case of the atmosphere’s unequal deposition of dirt. Another way for this sort of soil contamination to arise is by the transfer of soil contaminants with precipitation water.

The build-up of compounds containing the perchlorate anion (ClO4-) in some dry, arid habitats is an example of natural soil pollution. It is crucial to remember that certain pollutants might be created naturally in the soil as a result of particular environmental circumstances. For example, perchlorates can occur in soils containing chlorine and certain metals during a thunderstorm.

• Soil Pollution Caused by Anthropogenic Activities: Almost all occurrences of soil pollution are caused by human activity. Several human activities might pollute the soil.
• Industrial waste: With all of the chemicals they dump into the environment, whether they be in liquid or solid form, industries are by far the greatest polluters of the soil.
• Agricultural activities: Farmers are being compelled by the rising need for food to employ pesticides and fertilizers that only discharge poisons into the soil, killing beneficial microbes vital to plant development.
• Deforestation: When trees are cut down, the soil is prone to the elements, making it more susceptible to soil erosion. As a result, the ground becomes sterile and unfit for supporting plants.
• Urban waste: Waste that cannot be recycled is recklessly dumped, which looks bad and pollutes the environment. The decomposition of some of this garbage can take hundreds of years.

Types of Soil Pollutants

Pollutants and toxins make up soil contamination. Biological agents and some human activities are the principal polluters of soil. All soil contaminants are by-products of pollutants in the soil that pollute it. Agricultural methods that contaminate crops with pesticide chemicals, industrial waste, radioactive emissions, and urban or industrial waste are only a few examples of human activities that damage the soil.

Agricultural wastes

Pesticides, fertilizers, herbicides, slurry, trash, and manure heavily contaminate the soil where the crops are grown. Crops accumulate with components of the chemicals used and cause toxicity in the bodies of consumers.

Biological Agents

Manures and digested sludge from humans, birds, and animal excrement are introduced into the soil by biological organisms working inside the soil. Some are even disease-causative.

Industrial Wastes

Wastes from paper mills, oil refineries, sugar factories, petroleum industries, and others that manufacture steel, pesticides, textiles, pharmaceuticals, glass, cement, and other things.

Radioactive Wastes

Radium, thorium, uranium, nitrogen, and other radioactive materials from sources such as nuclear power plants, electrical appliances, etc., can seep into the soil and have hazardous effects.

Urban Wates

Garbage and other junk, dried sludge, and sewage from home and business waste make up urban waste.

Hospital Wastes

Medicines, tools, kits, sewage, etc., from hospitals that are contaminated mix in the soil and contaminate it. Many causative agents accumulate in other populations.

Examples of Soil Contaminants

There are many different types of contaminants that might contaminate the soil. Below are some illustrations of the most typical and harmful soil contaminants:

Lead: Even at the lowest concentrations, lead can be harmful, especially if it is present over an extended period of time. Lead paint, mining, foundries, car exhaust, building, and agricultural activities are some of the sources of lead in soil.

Mercury: Mercury can exist as a metal, gas, or salt, among other things. Mercury poisoning is quite harmful since it may be ingested or absorbed via the skin. Mining, coal combustion, alkali and metal processing, medical waste, volcanoes, and geologic deposits are all potential sources of mercury in soil. Mercury even accumulates in plants and vegetables produced on contaminated soils.

Arsenic: Arsenic is a naturally appearing element that may be discharged into the environment through volcanic eruptions or polluted groundwater in places with high arsenic concentrations. Mining, coal-fired power plants, timber mills, the electronics sector, foundry work, agriculture, and natural accumulation are all potential sources of arsenic.

Copper: Even while copper is necessary for humans in very small amounts, overexposure to it can be quite detrimental. Mining, foundry, and building operations might be sources of soil contamination.

Zinc: In regions where zinc is naturally present or mined, it is simple to pollute the soil and water. Zinc can result in a number of health issues when consumed in excess, whether purposefully through supplements or unintentionally through contact with polluted soil or water.

Insecticides/ Pesticides: Herbicides and insecticides are recognized pollutants for people. They can become toxic by direct skin contact, ingestion of food or water, or inhalation. When pollutants are exposed for an extended period of time or at high concentrations, they can have a major negative impact on people’s health, especially children and adults.

More Details About Various Soil Pollutants

Effects of Soil Pollution

A wide range of unfavorable effects caused by soil contamination harm humans, animals, plants, and the environment as a whole. Children are more vulnerable to disease; thus, contaminated soil is more dangerous to them.

Effects of Soil Pollution on Human Health

All three stages can have soil pollutants (solid, liquid, and gaseous). As a result, there are several ways that these toxins might enter the human body, either through direct skin contact or by being inhaled along with contaminated soil dust. It should be emphasized that several soil contaminants, including industrial solvents and petroleum hydrocarbons, have been connected to a variety of human congenital diseases. Soil contamination may harm people’s health in a number of ways.

Effects of Soil Pollution on Plants and Animals

Plant growth is hindered in such soils as the presence of soil pollution often leads to a decline in nutrient availability. Inorganic aluminium-contaminated soil has the potential to render plants toxic. Moreover, this form of pollution commonly elevates soil salinity levels, rendering it unsuitable for the growth and development of plant life.

When plants are cultivated in polluted soil, a phenomenon known as bioaccumulation occurs, wherein the plants absorb significant quantities of soil pollutants. Consequently, when herbivores consume these plants, the accumulated contaminants are transferred and make their way up the food chain.

This may cause several beneficial animal species to disappear or go extinct. Additionally, these toxins have the potential to ascend the food chain and eventually appear as illnesses in people.

Effects of Soil Pollution on the Whole Ecosystem

A clear link between soil pollution and air and water pollution exists because volatile chemicals in the soil can be blown into the sky by winds or seep into subsurface water reservoirs. It may also be a factor in acid rain. Several microorganisms that enhance soil texture and aid in the breakdown of organic materials are hostile to acidic soils. Thus, the detrimental impacts of soil contamination also affect the texture and quality of the soil. This type of pollution has a significant impact on crop productivity. Heavy metal contamination has rendered about 12 million tonnes of grain in China (worth around 2.6 billion USD) unsuitable for human consumption (as per studies conducted by the China Dialogue).

Also Read: Groundwater Pollution: Unveiling The Silent Threat To Our Planet