Ecological and Hygienic Significance of Soil & Municipal Solid Waste Disposal

Ecological Significance of Soil

  • Soil: Crucial ecological link for human survival, health, and life expectancy.
  • Ensures life by driving substance circulation through transformation and synthesis processes of organic matter.
  • Key processes:
    • Transformation and storage of solar energy.
    • Migration and exchange of chemical substances.
    • Determining chemical composition of food and water.
    • Influencing radioactive background, air quality, and climate.

Economic Importance of Soil

  • Main wealth: 90% of human food produced on/in it.
  • Soil degradation: Causes crop failures, famine, and poverty.
  • Degradation rate: Nature needs 1000 years to create a 3 cm soil layer; current degradation could eliminate topsoil in 60 years.

Sanitary-and-Hygienic Significance of Soil

  • Pollutants: Surface-active substances, hydrocarbons, heavy metals enter soil from waste and emissions.
  • Pollutant pathways: Contaminate water, plants, and air.
  • Standards consider:
    • Air-migratory.
    • Water-migratory.
    • Common-sanitary.
    • Translocational harmfulness.
  • Limiting indicator: The minimum of the above, used for setting MPC.
  • Soil is a natural environment for the neutralization of liquid and solid household and industrial waste due to self-purification processes.
  • Sanitary condition of soil is a set of physical, chemical and biological properties of soil, determining the quality and degree of its safety in epidemiological and hygienic aspects.
    -Indicators of the sanitary condition of soils are a set of sanitary-and-chemical, microbiological, helminthological and entomological characteristics of the soil.

Soil Pollution Indicators

  • Assessed using criteria for chemical, bacteriological, parasitological, entomological, and virological factors.
  • Evaluation: Based on worst indicator among all assessed.
  • Degrees of soil pollution: Clean, Acceptable, Moderately dangerous, Dangerous, Extremely dangerous.

Epidemiological Significance of Soil

  • Pathogens: Survive in soil, transmitting diseases through contact.
  • Survival factors: Pathogen species, soil type, pH, pollution.
  • Transmission: Direct contact, dust, food, water. Vectors: animals, rodents, insects.
  • Common pathogens: typhoid, polio viruses, ascaris eggs, anthrax spores.

Endemic Significance of Soil

  • Biogeochemical provinces: Imbalances of chemical elements lead to endemic diseases.
  • Examples: Caries, fluorosis, goiter.

Fluorosis

  • Cause: Excessive fluorine intake.
  • Effects: Dental and skeletal issues from high fluorine concentrations in water and food.
  • Dental fluorosis: Affects children up to 8 years old, causing enamel defects.
    • Severity: Graded by Dean’s Index, ranging from questionable to severe, with symptoms like white spots, brittleness and discoloration.
  • Skeletal fluorosis:
    • Early stage: joint stiffness, chronic pain in bones and joints.
    • Moderate stage: osteosclerosis, calcification of ligaments.
    • Advanced stage: restricted joint mobility, bony outgrowths, neurological complications.
  • Pathogenesis:
    • Fluoride incorporates into developing enamel cells during tooth formation.
    • Fluoride alters ameloblast function, causing enamel defects.
    • Leadsto weaker, porous enamel with discoloration.
    • Exposure timing and dose determine fluorosis extent.
  • Prevention:
    • Community water fluoridation guidelines
    • Optimal Fluoride Levels: Maintain 0.7−1.50.7 -1.5 mg/Lmg/L in water for maximum benefit without risk.
    • Individual prevention, supervise brushing and manage supplements
    • Alternative water sources: using sources with optimal fluoride content.
    • Water mixing: mixing water from several water sources with different fluorides content to to achieve optimal fluoride levels.
    • Defluoridation: removing excess fluoride from drinking water.

Endemic Goiter

  • Cause: Iodine deficiency causing thyroid enlargement.
  • Types of iodine deficiency:
    • Exogenous iodine deficiency. Primary is lack of iodine in soil. Secondary is soil contains a sufficient amount of iodine, but it is in a bound state with other chemical compounds and is not absorbed by plants.
    • Endogenous iodine deficiency is associated with a violation of iodine absorption in the body.
  • Classification:
    • Morphological: Diffuse, nodular, mixed.
    • Functional: Euthyroid, hypothyroid, hyperthyroid.
    • Swiss classification: I-II degree is endemic enlargement, III-V is true goiter.
  • Clinical features:
    • Enlarged thyroid gland, compression, hypothyroidism. In children: developmental delays.
  • Assessment:
    • Lenz-Bauer’s index: amount of men (III-V degree of enlargement) / amount of women (III-V degree of enlargement)
    • Kolomiytseva’s coefficient: (% of individuals with I − II degree of enlargement) / (% of individuals with III − V degree of enlargement)
  • Prevention:
    • Mass prevention: use of products that are initially rich in iodine and products artificially enriched with it. An effective prevention of the development of endemic goiter is the regular consumption of iodized table salt.
    • Group prevention: supplementation for pregnant and breastfeeding women, infants and young children, populations in severely deficient areas

Municipal Solid Waste (MSW) Problem

  • MSW: Waste from residential, public areas; includes paper, glass, food waste.
  • Scale: Developed countries generate 1-3 kg per person daily.
  • Russia: 100 billion tons accumulated, only 5% recycled; volume expected to double by 2025.

Consequences of Waste Pollution

  • Soil/groundwater pollution, ozone layer destruction.
  • Toxic emissions from burning landfills.
  • Landfills as habitats for disease vectors.
  • Acid rain from atmospheric toxins.

Key Problems in MSW Management

  • Financial: Inadequate tariffs.
  • Structural: Lack of specialized waste management utilities.
  • Systemic: Poor coordination among ministries.
  • Corporate: Limited private sector involvement.
  • Strategic: Absence of long-term planning.
  • Information: Lack of public awareness.
  • Construction: Issues with building designs hindering waste separation.
  • Marketing: Limited market for recycled materials.
  • Transportation: High costs due to long distances.

Other Aspects of the Solid Waste Problem

  • Increasing Waste Volume and Complexity.
  • Public Sentiment: Rising opposition to traditional landfilling methods.
  • Economic Considerations: Waste disposal prices are rising sharply.
  • Laws tightening waste management rules are being adopted at all levels of government.

Stages of Working with Municipal Solid Waste

  • Collection, storage, removal, Neutralization.

Methods of Municipal Solid Waste Collection

  • Unitary (unsorted collection): all waste types collected in a single container
  • Separate (selective) collection: waste sorted by type (glass, paper, metals, food waste) into separate containers

MSW Removal Methods

  • Transport System: One-stage (direct to disposal facility) or two-stage (via transfer stations) waste removal.
  • On-site Waste Crushing: Crushing waste at the source and disposing of it via the sewer system.
  • Pneumatic Pipeline Transport: Automated system transporting waste through pipelines to a central collection station.

Methods of Solid Waste Neutralization

  • Recycling and secondary use of the product (plastic, glass, metal, etc.)
  • Biometric method / composting (rotting waste to form humus)
  • Burning with energy recovery
  • Burning (incineration) without energy recovery;
  • burial of waste in landfills;
  • Dumping into the oceans

Waste Disposal Methods

  • Landfilling /Ocean dumping (liquidation methods).
  • Incineration (liquidation methods).
  • Incineration (with energy recovery) utilization methods.
  • Composting utilization methods.
  • Recycling utilization methods.

Solving the problem of household waste in different countries

  • Sweden: Buys waste from neighbors.
  • Germany: Schedule for removing large items and Christmas trees.
  • England: Two-Finger Litter Law.
  • USA: National RRR program (Reduce, Reuse, Recycle).
  • Switzerland: “Polluter pays” principle.

Conclusion

  • Waste increasing due to packaging and disposables.
  • Solution: Utilize disposal methods, maximize recycling, rationalize collection.