7.3A Solid domestic waste Notes

Waste Generation from Natural Resource Use

The use of natural resources in domestic, industrial, and agricultural activities generates large amounts of waste, which can be classified based on source (where it comes from) and type (its characteristics).

Waste management is crucial for reducing pollution, conserving resources, and protecting human health and ecosystems.

Sources of Waste

Domestic Waste (Household Waste)

1. Generated from homes and communities.
2. Includes food waste, packaging, plastics, textiles, and e-waste.
3. Can be biodegradable (food, paper) or non-biodegradable (plastics, metals).

Industrial Waste

1. Comes from factories, construction, and manufacturing processes.
2. Can include chemical waste, heavy metals, plastics, and e-waste.
3. Often hazardous and difficult to dispose of safely.

Agricultural Waste

1. Produced from farming, livestock, and forestry.
2. Includes crop residues, pesticides, animal manure, and food waste.
3. Can lead to soil and water pollution if not managed properly.

Types of Waste

E-Waste (Electronic Waste)

1. Includes discarded phones, laptops, batteries, and appliances.
2. Contains hazardous metals (lead, mercury, cadmium) and precious metals (gold, silver, palladium).
3. Poor disposal leads to toxic pollution and health risks.

Food Waste

1. Includes uneaten food from households, restaurants, and supermarkets.
2. Contributes to methane emissions when dumped in landfills.
3. A major problem in both developed (overconsumption) and developing (poor storage) countries.

Biohazardous Waste

1. Medical and biological waste from hospitals, labs, and research centers.
2. Includes infectious materials, used syringes, and contaminated PPE.
3. Improper disposal can spread diseases and harm wildlife.

Solid Domestic Waste (SDW)

It includes a variety of materials such as paper, plastics, organic waste, and metals, and is commonly known as municipal solid waste (MSW).

Types of Solid Domestic Waste

Paper and Cardboard

1. Includes newspapers, magazines, office paper, and packaging materials.
2. Easily recyclable but contributes significantly to waste volume.
3. Issue: If mixed with food waste, it becomes non-recyclable.

Glass

1. Includes bottles, jars, and windows.
2. 100% recyclable without quality loss.
3. Issue: If broken, it can be dangerous and hard to separate.

Metal

1. Includes aluminum cans, tin cans, and scrap metal.
2. Highly recyclable and energy-intensive to produce.
3. Issue: Some metals (e.g., coated cans) are difficult to recycle.

Plastics

1. Includes bottles, packaging, bags, and containers.
2. Difficult to degrade, contributing to ocean and land pollution.
3. Issue: Many plastics are non-recyclable due to contamination or mixed materials.

Organic Waste (Kitchen & Garden Waste)

1. Includes food scraps, fruit peels, and garden trimmings.
2. Biodegradable and can be used for composting.
3. Issue: In landfills, it releases methane, a potent greenhouse gas.

Packaging Waste

1. Includes wrappers, styrofoam, plastic films, and paper packaging.
2. Often single-use and hard to recycle due to mixed materials.
3. Issue: Contributes significantly to landfill waste and ocean pollution.

Construction Debris

1. Includes bricks, cement, wood, and tiles from renovation and demolition.
2. Recyclable, but often ends up in landfills due to poor sorting.
3. Issue: Contains hazardous materials (e.g., asbestos, lead paint).

Clothing & Textiles

1. Includes old clothes, shoes, and fabric waste.
2. Fast fashion has increased textile waste dramatically.
3. Issue: Many clothes are made of synthetic fibers, which are non-biodegradable.

Factors Affecting the Volume and Composition of Waste

1. The volume and composition of waste vary across time, locations, and societies due to multiple factors.
2. These include socio-economic, political, environmental, and technological influences.

Socio-Economic Factors

Economic development, income levels, and lifestyle choices play a crucial role in waste generation.

Higher-income countries:

1. Generate more packaging waste, electronics, and food waste due to consumerism.

Lower-income countries:

1. Generate less waste, but waste management infrastructure is weaker.
2. More organic waste due to reliance on fresh, unpackaged food.

Urban vs. Rural areas:

1. Urban areas generate more plastic, e-waste, and hazardous waste.
2. Rural areas have higher organic and agricultural waste.

Political Factors

Government policies and regulations determine waste management, recycling, and disposal methods.

Strict waste management laws → lower waste impact

Weak regulations → increased waste mismanagement

Political instability → poor waste management

Environmental Factors

The climate, geography, and natural disasters influence waste types and disposal.

Hot and humid climates → higher organic waste decomposition

Desert regions → minimal organic waste but high industrial waste

Natural disasters increase waste volume

Technological Factors

Advancements in production, consumption, and recycling technologies impact waste generation.

Advanced recycling technologies → reduced waste volume

E-commerce growth → increased packaging waste

Fast fashion → increased textile waste

Environmental and Social Impacts of Waste Management & Global Waste Trade

The production, treatment, and management of waste have significant environmental and social impacts, often affecting different locations from where the waste was initially generated.

This issue is particularly relevant to the global waste trade, where high-income countries export waste, especially hazardous and electronic waste, to low-income countries, creating environmental injustice.

Environmental Impacts of Waste Management

Air Pollution

1. Burning waste in open dumps releases toxic gases (e.g., dioxins, furans, methane, CO₂), contributing to climate change and respiratory diseases.

Soil and Water Contamination

1. Leachate (toxic liquid from landfills) pollutes groundwater and soil, harming ecosystems and agriculture.

Biodiversity Loss

1. Plastic waste in oceans affects marine life through entanglement and ingestion.

Social Impacts of Waste Management

Health Hazards for Informal Waste Workers

1. Many people in low-income countries rely on informal waste picking for survival, exposing them to toxic chemicals and injuries.

Displacement and Livelihood Loss

1. Landfills and waste incineration plants often displace indigenous and marginalized communities.

Environmental Injustice in Waste Trade

1. High-income countries export waste (especially e-waste, plastic, and toxic materials) to low-income countries with weaker regulations.

Addressing Waste-Related Environmental Injustice

1. Stronger Global Waste Trade Regulations: Enforce the Basel Convention to prevent illegal waste exports.
2. Improving Waste Management in High-Income Countries: Reduce reliance on exporting waste and invest in circular economy strategies (e.g., recycling, waste-to-energy technologies).
3. Better Working Conditions for Waste Workers: Provide protective gear, formal employment, and health support to informal waste workers.
4. Public Awareness & Sustainable Consumption: Reduce electronic waste, single-use plastics, and overconsumption through education and policies.

Pollution in Ecosystems: The Absorption Limits and the Concept of Biodegradability

1. Ecosystems naturally have the ability to absorb certain waste products and pollutants.
2. However, pollution occurs when harmful substances are introduced at a rate faster than the environment can break them down and transform them into harmless forms.

This imbalance leads to degradation of the environment, impacting biodiversity and ecosystem functions.

Pollution and Ecosystem Limits

1. Ecosystems' Absorption Capacity: Natural ecosystems, such as forests, oceans, and wetlands, have a limited capacity to absorb waste and pollutants, such as carbon dioxide, nutrients (like nitrogen and phosphorus), and organic matter.
2. Pollution Threshold: When waste is introduced at an unsustainable rate, ecosystems exceed their absorption threshold, resulting in pollution that disrupts ecological balance.

Types of Pollution and Their Impact:

1. Air Pollution: Excess CO₂ from fossil fuel burning or methane from agriculture.
2. Water Pollution: Overuse of nutrients (e.g., nitrogen and phosphorus) leading to eutrophication (algae blooms) in freshwater bodies.
3. Soil Pollution: Accumulation of heavy metals and pesticides that damage soil quality and affect agriculture.
4. Marine Pollution: Excess plastic waste and oil spills contaminate marine ecosystems, affecting marine life.

Biodegradability

1. Degradable Waste: Materials such as food scraps, paper, organic matter, and some plant-based materials are biodegradable and can be processed by natural organisms, often without causing long-term damage to the environment.
2. Non-Biodegradable Waste: Materials like plastics, metals, and synthetic chemicals do not break down easily and accumulate in the environment, contributing to long-term pollution.

Half-Life and its Role in Pollution

This concept is particularly relevant for non-biodegradable pollutants and substances that can accumulate in ecosystems.

The Importance of Half-Life in Pollution:

1. Long Half-Life Substances:
   1. Some pollutants, like radioactive materials, heavy metals (e.g., mercury, lead), and plastics, can persist in the environment for decades or centuries.
   2. Their long half-lives mean they pose a long-term threat to ecosystems and human health.
2. Short Half-Life Substances:
   1. Substances that degrade quickly (within days to weeks) are less damaging but still contribute to temporary pollution (e.g., some organic chemicals or biodegradable food waste).

Environmental Impacts of Pollution Beyond Ecosystems' Absorption Limit

When pollution exceeds an ecosystem's capacity to absorb it, it leads to:

1. Biodiversity Loss:
   1. Pollution can cause species extinction or disrupt food webs, as seen in eutrophication from excess nutrients or acid rain from sulfur dioxide.
2. Toxic Accumulation:
   1. Harmful substances can accumulate in the tissues of organisms over time, causing bioaccumulation and biomagnification, particularly in food chains.
   2. For example, mercury in fish affects higher trophic levels (humans, other predators).
3. Climate Change:
   1. Excessive carbon emissions lead to global warming, shifting weather patterns and causing extreme weather events, rising sea levels, and habitat loss.