The world of science widely acknowledges the Impact of Soils Pollution on Human Health. Monitoring soil-borne diseases and assessing indicators of diseases and fatalities caused by soil pollution is crucial.
Allow us to take you through 15 different effects of soil pollution on human health and their wide range of causes and possible solutions.
The World Health Organization (WHO) has identified ten primary contaminants posing risks to human health (WHO, 2010), with nine of them being soil-related contaminants, owing to their widely recognized effects on human well-being and broad geographical distribution.
Soil pollution refers to the contamination of soil with toxic substances. It is a serious environmental concern since it harbors many health hazards.
When the concentration of one or more such toxic substances is high enough to cause damage to living organisms, the soil is said to be contaminated.
Causes Of Soil Pollution & The Pollutants That Contaminate The Soil
Among a variety of others, the root cause of soil pollution is often one of the following:
- Agriculture (excessive/improper use of pesticides)
- Excessive industrial activity
- Poor management or inefficient disposal of waste
Contaminated soil can contain various types of pollutants, including:
- Pesticides: Pesticides are substances used to control pests, with types like herbicides (for weeds), insecticides (for insects), and fungicides (for parasitic fungi). Their involuntary spread, termed ‘pesticide drift,’ raises environmental issues like water and soil pollution. This can lead to the presence of soil contaminants, including those from pesticides.
- Microorganisms: Bacteria, viruses, and other pathogens can contaminate soil.
- Heavy Metals: These metals can originate from several sources such as mining activities, agricultural activities, electronic waste (e-waste), and medical waste. This includes heavy metals such as lead, mercury, cadmium, and arsenic.
- Organic Compounds: Including polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), pesticides, and industrial chemicals.
- Nutrients: Excessive levels of nutrients like nitrogen and phosphorus, often from fertilizers, can lead to soil contamination.
- Industrial Waste: Industrial waste discharge contributes to soil pollution, releasing pollutants like chlorinated solvents, dioxins (from pesticide production and waste incineration), plasticizers, polychlorinated biphenyls (PCBs), and carcinogenic petroleum hydrocarbons like benzene and methylbenzene. The petroleum industry creates many petroleum hydrocarbon waste products.
- Pharmaceuticals and Personal Care Products (PPCPs): This includes residues of medications and toiletries.
These pollutants can have diverse impacts on human health, ecosystems, and the environment.
Pathways For Human Exposure To Polluted Soil
Human health is intricately connected to the environment and its resources, particularly soil, which plays a crucial role in ecosystem functioning.
Soil contributes to about 95% of our food production, regulating gas exchange, storing greenhouse gasses and contaminants, and supporting terrestrial ecosystems by filtering and storing, and also redistribution of ground and surface water.
Through this means Contaminants can move between environmental components, posing health risks when soil is polluted.
There are Three Primary Ways People are Exposed to Soil Contaminants:
- Accidentally consuming contaminated food, dust, and soil particles, as well as ingesting crops and animal products.
- Intentional ingestion of soil.
- Inhalation of soil particles
Accidentally Consuming Contaminated Food, Dust, and Soil Particles, as Well as Ingesting Crops and Animal Products.
The World Health Organization (WHO) estimates that around 10% of the global population gets sick each year from consuming contaminated food, leading to approximately 420,000 annual deaths from acute or chronic poisoning.
Contaminants can be ingested through plants accumulating them from the soil, or from soil particles attaching to plants, meat, and dairy from animals that feed on tainted fodder.
Soil particles and dust settling on food or utensils are another inadvertent way contaminants reach humans, particularly affecting infants and children who tend to put their hands in their mouths.
The collaborative food standards initiative by FAO and WHO convenes regularly to set and revise permissible limits for contaminants in food based on the latest advancements in scientific knowledge.
Intentional Ingestion of Soil
Ingesting soil particles intentionally can offer detoxification benefits by absorbing harmful substances, while also addressing micronutrient deficiencies. However, consumption of polluted soil may elevate exposure to elements like trace metals, radionuclides, pesticides, and resistant bacteria.
Although some health issues like oxidative stress, toxicity, cancer, and neurological disorders have been linked to consuming contaminated soil, thorough assessments of soil quality, contaminant bioavailability, and health risks remain limited.
Pregnant women’s ingestion of contaminated soil can negatively impact fetal health, causing growth issues and preterm births.
Children are particularly vulnerable due to play-related soil ingestion and dermal contact. Mercury exposure risk was observed in children from polluted soils in a mining town, while adults’ risk remained within acceptable limits when considering various exposure pathways.
Inhalation of Soil Particles
General population inhalation, affecting more than half the population, happens in urban settings with local and distant contaminants.
Occupational exposure to soil contaminants through inhalation is prevalent, especially for workers in industries exposed to inorganic and organic pollutants released as vapors and dust. Examples include polluting industries, agrochemical-exposed farmers, and pollution cleanup employees.
Exposure conditions, contaminant levels, and bioavailability vary widely, with personal protection measures playing a regulatory role. The wider population is also at risk of inhaling soil contaminants, Urban areas, indoors and outdoors, contain local pollutants like vehicle exhaust and household chemicals, as well as global
Furthermore, the presence of environmental pollutants via various routes (such as soil, water, air, and organisms) is interconnected, facilitating an ongoing interchange of substances and energy.
Soil contamination encompasses a wide range of adverse outcomes impacting plants, animals, people, and the entire ecosystem.
Given children’s heightened vulnerability to illnesses, polluted soil poses a more significant risk to them.
Here is an outline of the key Effects of Soil Pollution.
The Effects of Soil Pollution on Human Health
Soil pollutants are present in solid, liquid, and gaseous states, allowing them to enter the human body through various routes like skin contact or inhaling contaminated soil particles.
The short-term effects of human exposure to polluted soil include Headaches, vomiting, nausea, Coughing, chest discomfort, breathing difficulties, Skin and eye irritation, Tiredness, and even more.
A variety of long-term ailments have been linked to soil pollution. Some health Effects of Polluted Soil on Humans are listed below.
Contaminated Food and Water
Soil pollution can lead to the contamination of crops and groundwater, which are essential sources of food and water for humans. This can result in the ingestion of harmful pollutants, for example; Arsenic.
While arsenic is involved in DNA methylation and preventing cancer, extended exposure can result in diverse health complications like skin abnormalities, respiratory challenges, heart problems, neurological alterations, and the development of cancer.
Additionally, contaminated drinking water is a primary avenue for human exposure to arsenic, particularly notable in South and Southeast Asian nations. This contamination originates from arsenic-containing minerals present in the soil, which leach into groundwater.
Another notable exposure path involves irrigating crops with water containing arsenic, which is especially significant in countries like Bangladesh. This practice has led to extensive health problems affecting millions of individuals.
According to WHO in 2018, Cancer ranks as the second most prevalent cause of death globally. One out of every five individuals developed cancer, and it was responsible for one out of every six deaths during that year.
Exposure to certain chemicals and pollutants in soil, such as polycyclic aromatic hydrocarbons (PAHs) and pesticides, has been linked to an increased risk of cancer.
The International Agency for Research on Cancer (IARC-WHO) established a categorization system for identifying hazards that can lead to cancer in humans. The IARC compilation comprises numerous soil pollutants.
The chance of developing cancer depends on exposure to these soil pollutants or a combination of them, via various pathways (ingestion, skin contact, or breathing), within a specific timeframe
The skin is the largest organ in our body and is made of layers that form an important line of defense against contaminants. Its primary role involves protecting against environmental components like chemicals, pathogens, radiation, and external hazards, while also aiding in temperature regulation and moisture retention.
Contact with contaminated soil can cause skin problems, including rashes, dermatitis, and irritation. The outermost layer, known as the stratum corneum, serves as the initial and crucial defense, resulting in minimal dermal absorption of pollutants in most cases.
Although the layers’ composition and arrangement limit the passage of environmental contaminants, certain substances can still breach this barrier and enter the bloodstream for distribution throughout the body.
Health risks from dermal contact depend on contaminant concentration, form, exposure frequency, and duration, toxicokinetics, age, exposure route, amount, duration, simultaneous exposure to multiple chemicals, and personal susceptibility factors including genetics.
Some pollutants in soil, such as organophosphate pesticides, can affect the nervous system and lead to neurological disorders.
Exposure to neurotoxicants can harm the nervous system’s structure and function, leading to disorders like autism, ADHD, intellectual disability, and cerebral palsy.
These disorders may have genetic or environmental origins, including exposure to various contaminants.
Soil pollutants like lead, mercury, and PCBs are known for their neurotoxic effects, and other substances like arsenic, DDT, pesticides, and certain chemicals have also been linked to neurotoxicity (US EPA, 2013).
Soil pollutants like phthalates and polychlorinated biphenyls (PCBs) can disrupt the endocrine system, leading to hormonal imbalances and related health issues.
The endocrine system releases a variety of hormones that play roles in controlling metabolism, maturation, growth, neurological development, and reproduction.
According to the International Programme on Chemical Safety, an endocrine disruptor is an external substance or mixture that changes the functioning of the endocrine system, leading to negative health effects in an intact organism, its offspring, or specific populations (IPCS, 2002).
Contaminants acting as endocrine disruptors employ multiple mechanisms. They may have a chemical structure resembling hormones, thus substituting for them in hormone receptors. This can disrupt normal hormone function, hormone synthesis, and metabolism, or trigger abnormal processes at various life stages.
Birth Defects and Developmental Delays
Exposure to certain soil pollutants during pregnancy can increase the risk of birth defects and developmental delays in children.
Teratogenicity is the capacity of any substance (whether physical, chemical, or biological) to cause abnormalities in the developing fetus when exposed during pregnancy.
The impact of teratogenic agents on fetal development can result in deformities, slowed growth, compromised neurodevelopment, functional issues, or even fetal demise before birth.
Other Long Term Health Effects of Soil Pollution on humans include:
Weakened Immune System
Soil pollution can weaken the immune system, making individuals more susceptible to infections and diseases.
Allergies and Asthma
Polluted soil can release allergenic substances that contribute to the development of allergies and asthma.
Airborne particles and pollutants from contaminated soil can contribute to cardiovascular diseases.
Dust and particulate matter from polluted soil can become airborne and lead to respiratory issues when inhaled.
Liver and Kidney Damage
Long-term exposure to soil pollutants can harm the liver and kidneys, affecting their proper functioning.
Cadmium is one of the main foodborne contaminants related to health problems, especially kidney issues.
Soil pollution has been associated with reproductive disorders, including infertility and reproductive organ damage.
Impacts on Children
Children are particularly vulnerable to soil pollution due to their behaviors, such as playing in contaminated soil, and their developing physiology.
Mental Health Impact
Living in areas with high soil pollution levels can contribute to stress and mental health issues.
Heavy Metal Poisoning
Soil pollution often involves heavy metals like lead, mercury, and cadmium, which can accumulate in the body over time and cause various health issues, including neurological and developmental problems.
How Can Soil Pollution Be Controlled?
Soil pollution can be managed through measures such as:
- Reducing chemical pesticide use and adopting sustainable farming practices.
- Proper waste disposal and treatment to prevent industrial contamination.
- Implementing effective land use planning to prevent soil degradation.
- Using eco-friendly products and promoting recycling to reduce waste.
- Implementing erosion control measures to prevent soil loss.
- Regular monitoring and remediation of contaminated sites.
Numerous technologies have emerged to address polluted soil including:
- Excavation and relocating of contaminated soils to distant, uninhabited sites.
- Pollutant extraction using thermal remediation – elevating temperatures to transition contaminants into vapor, which can then be collected through vapor extraction.
- Bioremediation or phytoremediation entails utilizing microorganisms and plants to detoxify the soil.
- Mycoremediation employs fungi to amass heavy metal pollutants.
Soil pollution poses a significant threat to human health, impacting various aspects such as food safety, water quality, and air contamination. Urgent measures are necessary to mitigate soil pollution’s adverse effects through sustainable practices and stringent regulations to safeguard both the environment and human well-being. Check out the 25 Effects of Environmental Pollution on Human Health.