Assessment of Pollution of Water, Air, and Soil, with a Focus on Air Pollution | Animal Husbandry & Veterinary Science Optional for UPSC PDF Download

Air Pollution: Understanding the Basics

• Definition: Air pollution refers to having too many harmful substances in the air, which can be bad for people's health and can damage property.
• Types of Contaminants:
  • Airborne Particulates: Solid and liquid particles of various sizes, ranging from large particles (over 20 microns) to fine particles (less than 0.05 microns).
  • Gases or Vapours: Includes permanent gases and compounds with boiling points below 200°C.

Understanding What's in the Air: Average Atmosphere Composition

• Major Gases
  • Nitrogen: 78% by volume (about 780,900 parts per million).
  • Oxygen: 21% by volume.
  • Argon: 0.93% by volume.
• Minor Gases:
  • Carbon dioxide, Neon, Helium, Methane, Krypton, Nitrous oxide, Hydrogen, Xenon: Present in smaller amounts, measured in parts per million.

Key Takeaways for Easy Understanding

• Air Pollution Defined: It's having too many harmful things in the air, which can make people sick and harm belongings.
• Types of Air Contaminants:
  • Solid and liquid particles of different sizes.
  • Gases or vapours, including both common gases and specific compounds.
• What's Normally in the Air? The air we breathe is mostly nitrogen and oxygen, with small amounts of other gases.
• Stay Informed: Monitoring and assessing air quality helps ensure a healthy environment for animals and people alike.

Understanding Air Pollution and Its Impact on Animals

Composition of Normal Outdoor Air:

• Nitrogen: 78%
• Oxygen: 21%
• Argon: 1%
• Carbon dioxide and traces of other inert gases.

Types of Air Contaminants and Examples

• Solid Particles: Carbon fly ash, ZnO, PbCl₂.
• Sulfur Compounds: H₂S, mercaptans.
• Organic Compounds: Aldehydes, hydrocarbons, tars.
• Nitrogen Compounds: NO, NO₂, NH₃.
• Oxygen Compounds: O₃, CO, CO₂.
• Halogen Compounds: HF, HCl.
• Radioactive Compounds: Gases, aerosols, etc.

Effects of Air Pollution on Animals

• Respiratory Syndrome Signs:
  • Cough, sneezing.
  • Conjunctival congestion.
  • Difficulty breathing.
  • Nasal discharge.
• Digestive Syndrome Signs:
  • Retching.
  • Diarrhea.
• General Impact:
  • Anorexia (loss of appetite).

Animal Fluorosis

• Fluorine toxicity often occurs through airborne agents.
• Chronic poisoning can result from the distribution of fluorine in air, soil, water, and animal feeds.

Gaseous Pollutants in Animal Production

• Animal waste contains gases like ammonia (NH₃), hydrogen sulfide (H₂S), and carbon monoxide (CO).
• Proper ventilation helps minimize health risks from these gases in farm buildings.

Water Pollution Simplified

• Water pollution is caused by substances that change the quality of water, making it less suitable for use.
• Pollutants can come from various sources and affect water's usability for different purposes.

Types of Water Pollution

• Natural Pollution:
  • Inevitable contamination from forest lands, contributing organic matter, algae, lime-forming organisms, grass, and decaying vegetation.
• Man-Made Pollution:
  • Large volumes of biological and chemical contaminants added by human activities.
  • Industries like packing plants, food processing, dairy, chemical, petroleum, and mining discharge pollutants into natural waters.

Principal Impurities in Water

• Suspended Matters:
  • Sand, silt, sewage, and vegetable matter.
• Dissolved Salts:
  • Bicarbonates, carbonates, and sulfates of calcium and magnesium.
• Dissolved Gases:
  • CO₂, O₂, H₂S.
• Suspended Bacteria and Pathogenic Organisms.
• Chemicals:
  • Natural chemicals, herbicides, insecticides, rodenticides, detergents, and other modern chemicals.

Soil Pollution Causes

• Industrialization and Population Growth:
  • Increased urbanization and intensive agriculture.
  • Industries discharge effluents with harmful elements into rivers and agricultural lands.
• Intensive Agriculture:
  • Heavy use of pesticides and fertilizers affects soil health and microorganisms.
• Coastal Area Issues:
  • Over-exploitation of water resources leads to saltwater intrusion, polluting groundwater and soils.
• Developmental Activities and Urbanization:
  • Rapid increase in urban areas and population.
  • High waste generation from multi-storeyed buildings and urban life.

Overall Impact

• Accumulation of pollutants in soil affecting its health.
• Changes in microbial activities and soil composition.
• Pollution from industrial, agricultural, and urban sources poses a threat to water and soil quality.

Sewage and Its Impact Simplified

• Sewage from Housing Units:
  • Each housing unit, with 200 flats (10 blocks), can discharge around 60,000 liters of sewage daily, even at a 50% collection rate.
  • In well-designed modern units, up to 80% of the water used can turn into sewage.
• Domestic vs. Urban Sewage:
  • Domestic sewage from households is generally safe and can be used for gardening.
  • Urban sewage is a mix of domestic waste and industrial pollutants, like chemicals used in processing.
• Industrial Influence on Sewage:
  • Industrial areas contribute harmful elements like chromium from tanneries or silica, sodium, and lignin from pulp and paper industries.
  • The level of toxic elements depends on the degree of industrialization in the area.
• Sewage Composition:
  • Less than 1% solid matter, mainly in the form of sludge.
  • Soluble toxic molecules in liquid, and insoluble or partly soluble toxic elements in solid sludge.
• Sewage Disposal in India:
  • Many Indian towns lack sewerage systems; open drains are common.
  • Waste waters often flow into rivers, waste lands, or lagoons, causing pollution.
• Pollutants in Waste Waters:
  • Elements like nitrogen, phosphorus, potassium, calcium, zinc, copper, manganese, iron, nickel, cobalt, cadmium, and chromium.
  • Some are beneficial for crops, while others like cadmium, nickel, zinc, and copper can be harmful.
• Impact on Soil and Water:
  • Continuous disposal of sewage on land leads to the accumulation of harmful elements affecting crop growth.
  • Organic material in sewage reduces oxygen availability in water, affecting crops and measured as Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD).
• Air Pollution from Industrial Activities:
  • Particulate pollution from industries, like cement factories, can damage soil, hinder water movement, air penetration, and affect plant germination.
• Saltwater Invasion Consequences:
  • Invasion of saltwater into groundwater results in pollution with contaminants like sodium, chloride, sulfate, and magnesium salts.
  • This pollution is irreversible and harms both soil and water quality.

Assessment of Pollution: Understanding the Impact in Simple Terms

Measuring Water Pollution

• BOD and COD Analysis:
  • BOD (Biochemical Oxygen Demand) and COD (Chemical Oxygen Demand) assess the pollution level in wastewater.
  • Higher values indicate greater risk and harm, prompting the need for reduction efforts.
• pH Level:
  • pH, measured by a pH meter, should ideally be near neutrality (6-8).
  • pH below 6 is acidic and can harm crops, increase metal solubility.
  • pH above 8 is alkaline, reducing trace element availability and causing potential toxicity.
• Electrical Conductivity:
  • Indicates the presence of soluble salts in water.
  • Lower values are better, while higher values can be harmful, requiring efforts to reduce them.
• Micronutrients and Heavy Metals:
  • Specialized equipment like Atomic Absorption Spectrophotometer assesses these harmful elements.
  • Even in low amounts, they can be harmful and should be below critical levels.

Soil Pollution Assessment

• Physical Properties Assessment:
  • Parameters like infiltration, hydraulic conductivity, and porosity assess soil damage from particulate particles.
• Chemical Analysis:
  • Soil analysis includes pH, electrical conductivity, and levels of trace and heavy metals.
  • Indicator plants and microbiological tests are sometimes used to assess soil health.

Livestock-Related Pollution

• Water Pollution from Livestock Farming:
  • Mainly from animal waste and fertilizers/pesticides used in forage production.
  • Ammonia volatilization from intensive livestock systems can contribute to nitrate pollution and acid rain.
• Food Chain Pollution:
  • Risks include direct transmission of diseases (e.g., bovine tuberculosis) to humans, especially through milk.
• Pollution within Livestock Systems:
  • Dust in livestock buildings and feed areas can cause respiratory problems for both livestock and humans.
  • Gaseous emissions, odors, and general pollution issues are significant within livestock systems.
• Industrial Impact on Livestock Environment:
  • Industrial contamination, including heavy metals, can affect soil and herbage around livestock areas.
  • Acid rain from industrial activity may indirectly impact livestock forage over wider areas.