--- title: "Soil pollutants, effects and remedies" subject: "Engineering Chemistry" chapter: 3 key: "semester_2/engineering_chemistry:soil-pollutants-effects-remedies" source: https://www.bctengineer.com/q/semester_2/engineering_chemistry/soil-pollutants-effects-remedies site: BCT Engineering --- # Soil pollutants, effects and remedies Engineering Chemistry · Chapter 3: Environmental Chemistry - Asked in: 2071 Magh, 1.5+2+1.5 marks; 2070 Bhadra, 1+2+2 marks; 2070 Magh, 1+2+2 marks; 2068 Magh, 1+2+2 marks; 2067 Mangsir, 1+2+1+1 marks (asked 5 times) - Video: [Soil Pollution| Causes/ Sources, Effects, Control/ Prevention| Soil Pollutants| Concepts of Botany](https://www.youtube.com/watch?v=Rz58_E67b2Q) — Concepts of Botany - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_2/engineering_chemistry/soil-pollutants-effects-remedies - Whole chapter: https://www.bctengineer.com/md/semester_2/engineering_chemistry/chapter-3 ## Question Write the pollutants responsible for soil pollution. Briefly describe the adverse affect of soil pollution and their possible remedies. ## Short answer Soil pollutants include agrochemicals, heavy metals, industrial wastes, and plastics. Adverse effects: loss of soil fertility, food chain contamination and biomagnification, groundwater pollution, death of soil organisms. Remedies: controlled chemical use, organic farming, waste segregation and recycling, bioremediation, effluent treatment, and strict laws. ## Answer #### Soil pollutants **Soil pollution** is the addition of harmful substances to the soil that lower its quality and productivity. The main pollutants are: - **Agrochemicals:** chemical fertilisers (nitrates, phosphates), pesticides and herbicides (DDT, BHC, malathion). - **Heavy metals:** Pb, Hg, Cd, As, Cr from mining, batteries, paints and industrial waste. - **Industrial wastes:** fly ash, sludge, acids, alkalis, dyes, tannery waste. - **Solid wastes:** plastics, polythene, glass, metal scrap, municipal garbage and e-waste. - **Others:** sewage sludge, radioactive wastes, oil spills, acid rain deposition, excess salts from irrigation. #### Adverse effects - Loss of soil fertility and reduced crop yield; soil becomes acidic, saline or toxic. - Toxic chemicals enter the food chain through plants and are biomagnified, causing cancer, kidney and nerve damage. - Leaching of pollutants contaminates groundwater and nearby streams (nitrates cause blue-baby syndrome). - Death of useful soil organisms such as earthworms and nitrogen-fixing bacteria. - Plastics block water movement and root growth; dumps cause bad smell and spread disease (flies, rats). - Soil erosion and land degradation. #### Possible remedies - Use fertilisers and pesticides in controlled amounts; adopt organic farming, compost and biofertilisers, and integrated pest management. - Segregate solid waste and follow reduce, reuse, recycle; compost biodegradable waste and produce biogas. - Ban or limit polythene; use biodegradable materials. - Treat industrial effluents before discharge; dispose of hazardous waste in secure landfills. - Bioremediation and phytoremediation (microbes or plants that absorb metals) to clean polluted soil. - Afforestation and crop rotation to prevent erosion; public awareness and strict laws. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. Which are the agrochemical causes of soil pollution? A. Chemical fertilisers (nitrates, phosphates), pesticides and herbicides such as DDT, BHC, malathion B. Fly ash and sludge C. Pb, Hg, Cd from batteries D. Plastics and polythene Answer: A. Agrochemicals are fertilisers, pesticides and herbicides; the others are industrial wastes, heavy metals and solid wastes. (Key point: Agrochemicals) 2. What is the effect of soil pollution on soil and crops? A. Higher yields because of added chemicals B. Loss of fertility and yield; soil becomes acidic, saline or toxic C. Soil becomes more fertile and porous D. Earthworm numbers increase Answer: B. Pollutants degrade the soil and reduce productivity. (Key point: Fertility loss) 3. Why are soil pollutants dangerous to humans? A. They stay in the soil and never reach plants B. They are destroyed by cooking in all cases C. They enter the food chain through plants and are biomagnified, causing cancer and kidney/nerve damage D. They only cause bad smells Answer: C. Plants take up toxins that move up the food chain and concentrate. (Key point: Food chain) 4. Which practice helps control soil pollution from farming? A. Heavy use of chemical pesticides B. Burning polythene on the field C. Unlimited use of nitrogenous fertilisers D. Controlled use of fertilisers and pesticides, organic farming, compost, integrated pest management Answer: D. Reducing agrochemicals and using organic methods cuts chemical load on soil. (Key point: Agri control) 5. How do phytoremediation and bioremediation clean polluted soil? A. Microbes or plants absorb/break down pollutants such as metals B. They seal pollutants with concrete C. They add more chemical fertiliser D. They increase soil salinity to kill pollutants Answer: A. Living organisms (microbes, plants) take up or degrade pollutants. (Key point: Remediation) ## Related in Engineering Chemistry - [Water pollution, pollutants and adverse effects](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Awater-pollutants-effects) — Engineering Chemistry, chapter 3 - [Organic/inorganic water pollutants, effects, remedies](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Awater-pollution-substances-effects-remedies) — Engineering Chemistry, chapter 3, asked 2× - [Air pollutants: effects and remedies](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aair-pollutants-effects) — Engineering Chemistry, chapter 3 - [Sources, effects and remedies of water pollution](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Awater-pollution-sources) — Engineering Chemistry, chapter 3, asked 2× - [Air pollution, pollutants, sources and remedies](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aair-pollution-sources-remedies) — Engineering Chemistry, chapter 3 - [Effects of soil pollution and its control](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Asoil-effects-control) — Engineering Chemistry, chapter 3 ## Related in other subjects - [Particulate pollutants: sources and effects](https://www.bctengineer.com/question.md?key=semester_7%2Fenvironment_and_pollution_control%3Aparticulate-pollutants-sources-effects) — Environment and Pollution Control, chapter 1 - [Water pollution: sources and effects](https://www.bctengineer.com/question.md?key=semester_7%2Fenvironment_and_pollution_control%3Awater-pollution-sources-effects) — Environment and Pollution Control, chapter 4 - [Air pollution: causes, effects and mitigation](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Aair-pollution-causes-mitigation) — Technology, Environment and Society, chapter 5, asked 3× - [Kathmandu air pollution: causes, effects, mitigation](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Akathmandu-air-pollution-causes) — Technology, Environment and Society, chapter 5