The harm of organic pollutants to soil mainly manifests in three aspects: damaging soil ecological functions, threatening agricultural product safety, and endangering human health. Pesticide organic pollutants such as organochlorine and organophosphorus remain in the soil for a long time, which not only inhibits microbial activity and leads to a decrease in soil fertility, but also enters the food chain through crop roots, accumulating in the human body and potentially causing neurological damage and endocrine disorders. Polycyclic aromatic hydrocarbon pollutants have strong carcinogenicity, and substances such as benzo [a] pyrene are difficult to degrade when adsorbed on soil particles. After being absorbed by crops or directly exposed to humans, they may induce various malignant tumors such as skin cancer and lung cancer. After the infiltration of petroleum hydrocarbon pollutants into the soil, a water barrier layer will be formed, which hinders the absorption of water and nutrients by plant roots. At the same time, monocyclic aromatic hydrocarbons such as benzene and toluene will penetrate the interior of plant tissues, causing widespread reduction or even complete crop failure.

The damage of these pollutants to soil ecosystems has long-term and cumulative characteristics. The half-life of organochlorine pesticides in soil can reach several decades, continuously poisoning soil microbial communities and hindering key ecological processes such as nitrogen and carbon cycling. Polycyclic aromatic hydrocarbons degrade slower under anaerobic conditions, and certain high ring substances can persist in soil for hundreds of years, continuously contaminating groundwater through rainwater leaching. Crops grown in contaminated soil may exhibit abnormal phenomena such as abnormal growth and reduced fruit size. For example, in a certain area where the soil is contaminated with petroleum, the empty shell rate of rice grown can reach as high as 40%, and the benzo [a] pyrene content in rice grains exceeds the standard by 12 times. More seriously, these organic pollutants can have a synergistic effect in the environment, and when pesticides coexist with polycyclic aromatic hydrocarbons, their toxicity often increases exponentially.

The pathways of harm to human health are complex and diverse. Organic pollutants ingested through consumption of contaminated agricultural products may initially manifest as symptoms such as loss of appetite and fatigue. Long term exposure can lead to abnormal liver function and weakened immunity, and exposure of pregnant women to such environments may cause fetal development defects. When the skin comes into direct contact with contaminated soil, polycyclic aromatic hydrocarbons can penetrate the stratum corneum and cause dermatitis and even cancer, while volatile organic compounds such as benzene can enter the human body through the respiratory system, damaging hematopoietic function. Some persistent organic pollutants, such as dioxins, may accumulate to dangerous levels in organisms at the top of the food chain through biomagnification, even at concentrations of only one trillionth in soil. These characteristics require a huge investment in the treatment of organic polluted soil. In the restoration project of a former coking plant site in the Yangtze River Delta, the cost of thermal desorption treatment for polycyclic aromatic hydrocarbon contaminated soil alone reached 3000 yuan per cubic meter.